proposed 3d seismic survey in the namibe basin off the ...eia.met.gov.na/screening/264_spectrum feir...

Proposed 3D seismic survey in the Namibe Basin

off the coast of northern Namibia

ENVIRONMENTAL IMPACT ASSESSMENT REPORT

SLR Project No.: 7NA.19097.00003

Report No.: 2

Revision No.: 0

October 2017

Spectrum Geo Limited

SLR Environmental Consulting (Namibia) (Pty) Ltd

SLR Ref. 7NA.19097.00003 Report No. 2

Proposed 3D seismic survey in the Namibe Basin off the coast of northern Namibia:

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DOCUMENT INFORMATION

Title Proposed 3D seismic survey in the Namibe Basin off the coast of northern Namibia

Project Manager Jeremy Blood

Project Manager e-mail [email protected]

Author Jeremy Blood

Reviewer Jonathan Crowther

Client Spectrum Geo Limited

Date last printed 30 October 2017

Date last saved 30 October 2017

Comments

Keywords Seismic survey, 3D, Namibe Basin, Namibia offshore, Oil and Gas

Project Number 7NA.19097.00003

Report Number 1

Revision Number 0

Status Final report for decision-making

REPORT COMPILED BY: Jeremy Blood REPORT REVIEWED BY: Jonathan Crowther

............................................................. .............................................................

Jeremy Blood Pr.Sci.Nat.; CEAPSA Jonathan Crowther Pr.Sci.Nat.; CEAPSA

Senior Environmental Consultant Technical Director

This report has been prepared by an SLR Group company with all reasonable skill, care and diligence, taking into

account the manpower and resources devoted to it by agreement with the client. Information reported herein is based on

the interpretation of data collected, which has been accepted in good faith as being accurate and valid.

No warranties or guarantees are expressed or should be inferred by any third parties.

This report may not be relied upon by other parties without written consent from SLR.

SLR disclaims any responsibility to the Client and others in respect of any matters outside the agreed scope of the work.




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EXPERTISE OF ENVIRONMENTAL ASSESSMENT PRACTITIONER

NAME Jonathan Crowther

RESPONSIBILITY ON PROJECT Quality control and report review

QUALIFICATIONS B.Sc. Hons (Geol.), M.Sc. (Env. Sci.)

PROFESSIONAL REGISTRATION Pr.Sci.Nat. (Reg. No. 400145/93), CEAPSA

EXPERIENCE IN YEARS 29

EXPERIENCE

Jonathan Crowther has been involved in environmental consulting since

1988 and is a Technical Director of SLR Consulting (South Africa).

Jonathan has expertise in a wide range of environmental disciplines,

including Environmental Impact Assessments, Environmental Management

Plans / Programmes, Environmental Planning and Review, Environmental

Auditing and Monitoring, Environmental Control Officer, Public Consultation

and Facilitation. He has project managed a number of offshore oil and gas

Environmental Impact Assessments for various exploration and production

activities in South Africa and Namibia and has extensive experience in

projects related to roads, property developments and waste landfill sites.

NAME Jeremy Blood

RESPONSIBILITY ON PROJECT Project management and report compilation

QUALIFICATIONS B.Sc. Hons (Bot.), M.Sc. (Cons. Ecol.)

PROFESSIONAL REGISTRATION Pr.Sci.Nat. (Reg. No. 400164/06), CEAPSA


EXPERIENCE

Jeremy Blood has worked as an environmental assessment practitioner

since 1999 and has been involved in a number of projects covering a range

of environmental disciplines, including Basic Assessments, Environmental

Impact Assessments and Environmental Management Programmes.

Jeremy has gained experience in a wide range of projects relating to

mining (e.g. offshore oil and gas exploration and production), infrastructure

projects (e.g. roads, water and power supply), waste management (e.g.

landfill sites), water projects (e.g. rivers, dams and wetlands), and housing

and industrial developments.

NAME Werner Petrick

RESPONSIBILITY ON PROJECT EIA process review and quality control

DEGREE M. Env Mgt (Potchefstroom University), B. Eng (University of Pretoria)

PROFESSIONAL REGISTRATION Environmental Assessment Practitioner Association of Namibia (Reviewer

& Lead Practitioner)


EXPERIENCE

Werner Petrick is a director of SLR Environmental Consulting (Namibia)

(Pty) Ltd and the Environmental Assessment Practitioner / Team Manager

in Namibia. With SLR he is responsible for conducting environmental

impact assessments, environmental management systems, stakeholder

engagement, mine closure planning, environmental training and auditing.

He is also responsible for managing the Environmental Assessment Team

and associated activities.




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NAME Marvin Sanzila

RESPONSIBILITY ON PROJECT Management of the public participation process, including I&AP notification

and assimilation of comments

DEGREE B.Sc. Nat Res (University of Namibia)

PROFESSIONAL REGISTRATION -


EXPERIENCE

Marvin Sanzila has assisted in the undertaking of various Environmental

Impact Assessments, including project management, legal reviews, public

participation, and impact assessment. Prior to SLR, Marvin was an

Environmental Compliance Coordinator for the Langer Heinrich Uranium

mining project.




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PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE BASIN

OFF THE COAST OF NORTHERN NAMIBIA

EXECUTIVE SUMMARY

1. INTRODUCTION

1.1 PROJECT BACKGROUND

Spectrum Geo Limited (hereafter referred to as “Spectrum”) is proposing to undertake a speculative three-

dimensional (3D) seismic survey to investigate for oil and gas reserves in the Namibe Basin off the coast of

northern Namibia, roughly between the Namibian – Angolan border (17º 14’ S) and 18º 08’ S.

Figure 1: Location of the proposed survey area in the Namibe Basin off the coast of northern

Namibia (after Spectrum).




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Spectrum has applied to undertake the seismic survey under a Multi-Client Agreement with the National

Petroleum Corporation of Namibia (NAMCOR). Although this is not covered specifically by the Petroleum

(Exploration and Production) Act, 1991 (No. 2 of 1991), the Ministry of Mines and Energy (MME) has

indicated that the requirements are the same as for an Exploration Licence. Thus a Petroleum Agreement

must be entered into between MME and Spectrum, a requirement of which is that a study into the baseline

environmental conditions of the survey area be undertaken.

SLR Environmental Consulting (Namibia) (Pty) Ltd (SLR) has been appointed to investigate the baseline

environmental conditions in the proposed survey area and to assess the potential impacts of the proposed

seismic survey and present the findings in an EIA Report. This report presents the findings and

recommendations of the EIA process and is submitted to MME for approval in consultation with other

relevant Ministries, e.g. the Ministry of Fisheries and Marine Resources (MFMR) and the Ministry of

Environment and Tourism (MET).

2. EIA PROCESS

2.1 SPECIALIST STUDIES

Two specialist studies were undertaken to address the key issues that required further investigation, namely

the impact on fishing and marine fauna. The specialist studies involved the gathering of data relevant to

identifying and assessing environmental impacts that may occur as a result of the proposed project. These

impacts were then assessed according to pre-defined rating scales. Specialists also recommended

appropriate mitigation / control or optimisation measures to minimise potential negative impacts or enhance

potential benefits, respectively.

2.2 COMPILATION AND REVIEW OF EIA REPORT

The findings of the specialist studies and other relevant generic information obtained from previous studies

and seismic survey “close-out” reports have been integrated into the EIA Report. This report, therefore,

contains the key information from each of the specialist studies, including the description and assessment of

impacts. Each impact is described and assessed in terms of the nature of the effect, duration, extent,

intensity and significance level, which is assigned according to pre-defined rating scales.

A draft version of the EIA Report was distributed for a 30-day comment period from 7 August to 7 September

2017 in order to provide authorities and I&APs with an opportunity to comment on any aspect of the

proposed project and the findings of the EIA process. Steps undertaken as part of the EIA Report review

process are summarised below.

• A preliminary I&AP database of authorities, Non-Governmental Organisations, Community-based

Organisations and other key stakeholders was compiled using databases of previous studies

undertaken in area. Additional I&APs were added to the database based on responses to the

advertisements and comments received during the review process. To date 165 I&APs have been

registered on the project database;

• A notification letter (in English and Afrikaans) was distributed to all identified I&APs. The letter

informed them of the release of the EIA Report and where the report could be reviewed. To facilitate

the commenting process, a copy of the Executive Summary was enclosed with each letter; and

• Advertisements announcing the proposed project, the availability of the EIA Report and comment

period were placed in the Namibian (English) and Republikein (Afrikaans) newspapers on 7 August

2017.




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Two written submissions were received during the EIA Report review and comment period. These

comments have been collated, and responded to, in a Comments and Responses Report (see Appendix 4.5

of the main report). The key issues raised relate to the potential impact of seismic noise on marine fauna

and associated mitigation measures (including soft-start procedures, survey scheduling and survey

termination).

3. PROJECT DESCRIPTION

3.1 INTRODUCTION

Seismic surveys are carried out during oil and gas exploration activities in order to investigate subsea

geological formations. During seismic surveys, high-level, low frequency sounds are directed towards the

seabed from near-surface sound sources (source arrays) towed by a seismic vessel. Signals reflected from

geological interfaces below the seafloor are recorded by multiple receivers (or hydrophones) towed in a

single or multiple streamer configuration (see Figure 2). Analyses of the returned signals allow for

interpretation of subsea geological formations.

Seismic surveys are undertaken to collect geophysical data in either 3D or 2D mode. For this investigation

Spectrum is proposing to undertake a 3D seismic survey.

Figure 2: Principles of offshore seismic acquisition surveys (from fishsafe.eu).

3.2 SEISMIC SURVEY PROGRAMME

The proposed 3D seismic survey would be 12 940 km2 in extent (see Figure 1). Water depths in the survey

area range from approximately 150 m in the east to depths greater than 4 000 m in the west. The survey

area is located 27 km from shore at its closest point.

Although survey commencement would ultimately depend on a licence award date, Spectrum proposes to

commence with the 3D seismic survey in the fourth quarter of 2017. It is anticipated that the proposed 3D

seismic would take in the order of nine (9) to ten (10) months to complete.




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3.3 SEISMIC CONTRACTOR AND SURVEY / SUPPORT VESSELS

Spectrum proposes to contract BGP Inc. to undertake the proposed 3D seismic survey. Although the survey

vessel to be used would depend on vessel availably, currently BGP proposes to use the vessel, BGP

Prospector for the seismic survey.

3.4 ANTICIPATED AIRGUN AND HYDROPHONE ARRAY SPECIFICATIONS

Anticipated specifications for the source and receiver arrays are summarised in Table 1.

Table 1: Airgun and hydrophone array specifications.

No. of airgun arrays 2

No. of active airguns 10 to 12 per string

Airgun array volume 4 200 cu.in

Airgun operating pressure 2 000 – 3 000 psi

Depth of airgun 5 to 8 m*

Distance of airgun behind vessel 50 to 200 m

Streamers (number and length) 12 x 8 000 m

Streamer depth 9 to 17 m*

*Note: Subject to final survey acquisition design

3.5 SUPPORT SERVICES

Vessel supplies, including food, water, and fuel will likely be loaded at the Port of Walvis Bay. Alternatively,

a support vessel would be used to perform logistics support to the seismic vessel, including crew changes.

Crew changes would occur in the Port of Walvis Bay or via helicopter and / or supply vessel (most likely

alternative) from Walvis Bay.

Bunkering of the survey vessel is expected to be undertaken at the Port of Walvis Bay or at sea during the

survey. Standard operating procedures for refuelling will be adhered to at all times.

3.6 EXCLUSION ZONE

Under the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972,

Part A, Rule 10), a seismic survey vessel that is engaged in surveying is defined as a “vessel restricted in its

ability to manoeuvre” which requires that power-driven and sailing vessels give way to a vessel restricted in

her ability to manoeuvre. Vessels engaged in fishing shall, so far as possible, keep out of the way of the

seismic survey operation. Furthermore, in terms of the Petroleum (Exploration and Production) Act, 1991

(No. 2 of 1991) a seismic vessel is considered to be an “offshore installation” and as such it is protected by a

500 m safety zone. It is an offence for an unauthorised vessel to enter the safety zone.

In addition to a statutory 500 m safety zone, a seismic contractor would request a safe operational limit (that

is greater than the 500 m safety zone) that it would like other vessels to stay beyond. Typical safe

operational limits for 3D surveys are illustrated in Figure 3.




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Figure 3: Typical configuration and safe operational limits for 3D seismic survey operations.

4. DESCRIPTION OF THE AFFECTED ENVIRONMENT

4.1 GEOPHYSICAL CHARACTERISTICS

The continental shelf off central Namibia is variable in width. Off the Orange River the shelf is wide (230 km)

narrowing to the north and reaching its narrowest point (90 km) off Chameis Bay, before widening again to

130 km off Lüderitz. Off Terrace Bay the shelf gives rise to the Walvis Ridge, an underwater plateau

extending south-westwards far into the south Atlantic, before narrowing again towards Cape Frio. The

salient topographic features of the shelf include the relatively steep descent to about 100 m, the gentle

decline to about 180 m and the undulating depths to about 200 m. The variable topography of the shelf is of

significance for nearshore circulation and for fisheries. Water depths in the survey area range from

approximately 150 m in the east to depths greater than 4 000 m in the west.

The inner shelf is underlain by Precambrian bedrock, whilst the middle and outer shelf areas are composed

of Cretaceous and Tertiary sediments. As a result of erosion on the continental shelf, the unconsolidated

sediment cover is generally thin, often less than 1 m. Sediments are finer seawards, changing from sand on

the inner and outer shelves to muddy sand and sandy mud in deeper water. However, this general pattern

has been modified considerably by biological deposition (large areas of shelf sediments contain high levels

of calcium carbonate) and localised river input. Off central Namibia, the muddy sand in the nearshore area

off Henties Bay gives way to a tongue of organic-rich sandy mud, which extends from south of Sandwich

Harbour to ~ 20°40’S. These biogenic muds are the main determinants of the formation of low-oxygen

waters and sulphur eruptions off central Namibia. Further offshore these give way to muddy sands, sands

and gravels before changing again into mud-dominated seabed beyond the 500 m contour.

Paravane

3 km

4 km

4 km

3 km

8 km

12 km

6 km 6 km

Airgun array

Hydrophone streamers

Tail-buoys

DAYLIGHT EXCLUSION ZONE

NIGHT TIME EXCLUSION ZONE

Not to scale




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4.2 BIOPHYSICAL CHARACTERISTICS

The climate of the Namibian coastline is classified as hyper-arid with typically low, unpredictable winter rains

and strong predominantly southerly or south-westerly winds. Further out to sea, a south-easterly component

is more prominent. The Namibian coastline is characterised by the frequent occurrence of fog, which occurs

on average between 50 and 75 days per year, being most frequent during the months of February through

May. Average precipitation per annum along the coastal region between Walvis Bay and the Kunene River

is <15 mm. Due to the combination of wind and cool ocean water, temperatures are mild throughout the

year. Coastal temperatures average around 16°C, gradually increasing inland. In winter, maximum diurnal

shifts in temperature can occur caused by the hot easterly ‘berg’ winds which blow off the desert. During

such occasions temperatures up to 30°C are not uncommon.

The Namibian coastline is strongly influenced by the Benguela Current system. It is characterised by coastal

upwelling of cold nutrient-rich water, and is an important centre of plankton production, which supports a

global reservoir of biodiversity and biomass of sea life. Current velocities in continental shelf areas generally

range between 10 to 30 cm/s. The flows are predominantly wind-forced, barotropic and fluctuate between

poleward and equatorward flow.

The wave regime along the southern African West Coast shows no strong seasonal variation with virtually all

swells throughout the year coming from the south-west to south direction. In winter there is a slight increase

in swell from south-west to south direction. In common with the rest of the southern African coast, tides are

semi-diurnal, with a total range of some 1.5 m at spring tide, but only 0.6 m during neap tide periods.

The continental shelf waters of the Benguela system are characterised by low oxygen concentrations with

<40% saturation occurring frequently. The low oxygen concentrations are attributed to nutrient

remineralisation in the bottom waters of the system. Oxygen deficient water can affect the marine biota at

two levels. It can have sub-lethal effects, such as reduced growth and feeding, and increased inter-moult

period in the rock-lobster population. On a larger scale, periodic low oxygen events in the nearshore region

can have catastrophic effects on the marine communities.

Closely associated with seafloor hypoxia, particularly off central Namibia, is the generation of toxic hydrogen

sulphide and methane within the organically-rich, anoxic muds following decay of expansive algal blooms.

Under conditions of severe oxygen depletion, hydrogen sulphide (H2S) gas is formed by anaerobic bacteria

in anoxic seabed muds. This is periodically released from the muds as ‘sulphur eruptions’, causing upwelling

of anoxic water and formation of surface slicks of sulphur discoloured water. These eruptions strip dissolved

oxygen from the surrounding water column, resulting in mass mortalities of marine life.

4.3 BIOLOGICAL CHARACTERISTICS

Biogeographically, the study area falls into the warm-temperate Namib Province, which extends northwards

from Lüderitz into southern Angola. The portion of the proposed survey area that extends beyond the shelf

break onto the continental slope and into abyssal depths falls into the Atlantic Offshore Bioregion.

The coastal, wind-induced upwelling characterising the Namibian coastline, is the principle physical process

which shapes the marine ecology of the central Benguela region. The Benguela system is characterised by

the presence of cold surface water, high biological productivity, and highly variable physical, chemical and

biological conditions. Communities within marine habitats are largely ubiquitous throughout the southern

African West Coast region, being particular only to substrate type or depth zone. These biological

communities consist of many hundreds of species, often displaying considerable temporal and spatial

variability (even at small scales).




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Plankton is particularly abundant in the shelf waters off Namibia, being associated with the upwelling

characteristic of the area. The spatial and temporal variation in upwelling results in considerable variability in

phytoplankton biomass in both longshore and offshore directions. As the majority of zooplankton are primary

consumers, zooplankton biomass is strongly correlated to that of phytoplankton (i.e. low biomass

immediately following upwelling, with increases tracking the development of phytoplankton blooms). Since

the proposed survey area is located offshore of an upwelling cell, it is expected that phytoplankton and

zooplankton abundances will be seasonally variable. The preferred spawning grounds of numerous

commercially exploited fish species are located off central and northern Namibia, which is very important to

commercial fisheries. The proposed seismic survey area overlaps with the summer to autumn spawning

area for anchovy, pilchard and horse mackerel, but lies offshore of cob and steenbras spawning areas

(see Figure 4). Therefore, ichthyoplankton abundances in the survey area are expected to be seasonally

high.

Figure 4: Survey area in relation to major fish spawning areas in the central and northern

Benguela region.

Species diversity, abundance and biomass of benthic invertebrate macrofauna increases from the shore to

80 m depth. Further offshore to 120 m depth, the midshelf is a particularly rich benthic habitat, which acts as

an important source of food for carnivores, such as cephalopods, mantis shrimp and demersal fish species.

Outside of this rich zone biomass declines. Many organisms have adapted to low oxygen conditions by

developing highly efficient ways to extract oxygen from depleted water.

Due to the cold temperate nature of the region, the fish fauna off the Namibian coast is characterised by a

relatively low diversity of species compared with warmer oceans. However, the upwelling nature of the

region results in huge biomasses of specific species that support an important and lucrative commercial

fishery off this coast.




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The Namibian coastline sustains large populations of breeding and foraging seabird and shorebird species,

which require suitable foraging and breeding habitats for their survival. In total, 11 species of seabirds are

known to breed along the southern Namibian coast. Most seabirds breed on islands or on the man-made

guano platforms in Walvis Bay, Swakopmund and Cape Cross. Most of the seabird species breeding in

Namibia feed relatively close inshore (10-30 km). Cape Gannets, however, are known to forage up to

140 km offshore and African Penguins have also been recorded as far as 60 km offshore. The nesting

grounds for Gannets and African Penguins are at Ichaboe Island, Halifax and Possession Islands, which lie

over 500 km to the south of the proposed survey area.

Five species of turtles occur off Namibia. However, only the Leatherback turtle is likely to be encountered

within the survey area, but their abundance is expected to be low.

Thirty-two species of whales and dolphins are known or likely to occur in Namibian waters. The distribution

of cetaceans in Namibian waters can largely be split into those associated with the continental shelf and

those that occur in deep, oceanic water. Importantly, species from both environments may be found in the

continental slope (200 to 2 000 m) making this the most species-rich area for cetaceans. Cetacean density

on the continental shelf is usually higher than in pelagic waters, as species associated with the pelagic

environment tend to be wide ranging.

The Cape fur seal is the only seal species that has breeding colonies along the Namibian coast. The closest

seal colonies to the proposed survey are located at Cape Frio and Möwe Bay, approximately 60 km and

200 km south of the proposed survey area, respectively. The proposed survey area thus falls within the

foraging range of seals (up to 220 km offshore) from these nearby colonies.

4.4 SOCIO-ECONOMIC ENVIRONMENT

The commercial fishing sectors that operate off the coast of northern Namibia include: demersal trawl, mid-

water trawl, deep-water trawl, small pelagic purse-seine, large pelagic long-line, demersal long-line, tuna

pole, line-fish, deep-sea crab and rock lobster. The spatial extent of the sectors that could be impacted by

the proposed seismic survey is depicted in Figure 5. The proposed survey would not impact the rock lobster

sector, tuna pole, deep-sea trawl and traditional line-fish sectors.

The majority of shipping traffic is located on the outer edge of the continental shelf, with traffic inshore of the

shelf largely comprising fishing and mining vessels. The main shipping lanes are located well to the west of

the proposed survey area. Fishing vessels would be encountered over the survey area.

Exploration for oil and gas is currently undertaken in a number of offshore licence blocks. Namibian Licence

Blocks in relation to the proposed survey area are shown in Figure 1.

Marine diamond mining is currently limited to the southern half of the Namibian offshore. Although the

proposed survey area overlaps with a number of offshore Exclusive Prospecting Licences (EPLs) and Mining

Licences, current activities in the EPLs are minimal to non-existent with the only active operations being

diamond mining south of Lüderitz. There is also a proposal to mine phosphate in a licence area

approximately 120 km south of Walvis Bay, well to the south of the proposed survey area.

Numerous conservation areas and a MPA exist along the Namibian coastline, although these are all located

inshore and to the south of the proposed survey area.




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Hake demersal trawl effort (1992 to 2010) Mid-water trawl catch (1997 – 2011)

Large pelagic long-line catch (2008 - 2013) Demersal long-line catch (2000 – 2010)

Pelagic purse-seine effort (1996 - 2011) Deep-sea crab catch (2003 – 2011)

Figure 5: Summary of the key fisheries operating in the vicinity of the proposed survey area.




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5. IMPACT ASSESSMENT CONCLUSIONS

A summary of the assessment of potential environmental impacts associated with the proposed seismic

survey is provided below and in Table 2.

The majority of the impacts associated with the seismic survey would be of short-term duration and limited to

the immediate survey area. As a result, the majority of the impacts are considered to be of INSIGNIFICANT

to LOW significance after mitigation.

The two key issues associated with the proposed seismic survey relate to:

• The potential impact on marine mammals (physiological injury and behavioural avoidance) as a result

of seismic noise; and

• The potential impact on the fishing industry (vessel interaction, disruption to fishing operations and

reduced catch) due to the presence of the survey vessel with its associated safety zone, potential fish

avoidance of the survey area and changes in feeding behaviour.

Assuming the 10-month survey would extend into the key cetacean migration and breeding period from the

beginning of June to the end of November, the impact on cetaceans is considered to be of medium to high

significance without mitigation. In order to mitigate this impact, it is strongly recommended that the proposed

seismic survey programme be undertaken in two phases in order to avoid this key period. As several of the

large whale species (including mother-calf pairs) remain abundant off the northern Namibian coast during

December and January, it is further recommended that PAM technology, which detects animals through their

vocalisations, in combination with thermal imaging cameras be continuously implemented should surveying

occur during this period. Various other measures are recommended to further mitigate the potential impact

on cetaceans, including a 30-minute pre-watch period, “soft-start” procedure, temporary termination of

survey, etc. The recommended approach of undertaking the survey over two seasons, along with the other

proposed mitigation, would reduce potential impacts on cetaceans to VERY LOW to LOW.

Although most of the impacts on cetaceans are assessed to have VERY LOW to LOW significance with

mitigation, the impact could be of higher significance due to the limited understanding of how short-term

effects of seismic surveys relate to longer term impacts. For example, if a sound source displaces a species

from an important feeding or breeding area for a prolonged period, impacts at the population level could be

more significant. This said, the southern right and humpback whale populations are reported to be

increasing by 7% and 5% per annum, respectively, over a time when seismic surveying frequency has

increased, suggesting that, for these populations at least, there is no evidence of long-term negative change

to population size as a direct result of seismic survey activities.

The key fishing sectors in the vicinity of the proposed survey area, based on commercial fishing records, are

the mid-water trawl, large pelagic long-line and deep-sea crab sectors. The potential impact on these

sectors over a 10-month period is considered to be of MEDIUM significance with mitigation. Although the

potential impact on the other sectors (including demersal trawl, small pelagic purse-seine, demersal long-line

and deep-sea crab sectors) ranges from VERY LOW to LOW significance with mitigation, if fish avoid the

survey area and / or change their feeding behaviour it could have a more significant impact on these sectors.

Research has, however, shown that behavioural effects are generally short-term with duration of the effect

being less than or equal to the duration of exposure, although these vary between species and individuals,

and are dependent on the properties of the received sound. Any interaction between the seismic survey

vessels and fishing vessels could also increase the significance of the impact of these fisheries. Thus it is

important that the operator engage timeously with the fishing industry prior to and during the surveys in order

to minimise any interaction. There would be NO IMPACT on the rock lobster sector, tuna pole, deep-sea

trawl and traditional line-fish sectors.




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Prior to survey commencement it is recommended that key stakeholders (including fishing industry

associations) are informed of the proposed survey details (including navigational co-ordinates of the survey

areas, and timing and duration of proposed activities) and the likely implications thereof (500 m safety zone

and proposed safe operational limits). In addition, it is recommended that Radio Navigation Warnings and

Notices to Mariners are provided regularly during survey operations. The placement of an on-board

Fisheries Liaison Officer (FLO) would also help ensure that ongoing communication (via daily reports) is

maintained between the survey vessels and the fishing industry and other users of the sea. This proposed

regular communication with fishing vessels in the vicinity of the proposed surveys would minimise the

potential disruption to fishing operations and risk of gear entanglements.

Table 2: Summary of the significance of potential impacts related to the proposed 3D seismic

survey off the coast of northern Namibia. (Note: * indicates that no mitigation is

possible and / or considered necessary, thus significance rating remains).

Potential impact Probability

(with mitigation)

Significance

Without

mitigation

With

mitigation

Normal seismic / support vessels and helicopter operation:

Emissions to the atmosphere Definite VL VL

Deck drainage into the sea Highly probable VL VL

Machinery space drainage into the sea Highly probable VL VL

Sewage effluent into the sea Highly probable VL VL

Galley waste disposal into the sea Highly probable VL VL

Solid waste disposal into the sea Improbable Insig. INSIG.

Accidental oil spill during

bunkering / refuelling

Within port limits Improbable Insig. INSIG.

Offshore Improbable L VL

Noise from seismic and support vessel operations Probable VL VL*

Noise from helicopter operation Improbable L-M VL

Impact of seismic noise on marine fauna:

Plankton Probable VL VL*

Invertebrates Physiological injury Probable VL VL*

Behavioural avoidance Probable VL VL*

Fish Physiological injury Improbable L VL

Behavioural avoidance Improbable L VL

Spawning and recruitment Improbable L VL

Masking sound and communication Improbable VL VL

Indirect impacts on food sources Improbable VL VL

Diving seabirds Physiological injury Improbable VL VL



Non-diving seabirds Physiological injury Improbable Insig. INSIG.

Behavioural avoidance Improbable Insig. INSIG.

Turtles Physiological injury Improbable L VL


Masking sound and communication Improbable Insig. INSIG.


Seals Physiological injury Probable L VL

Behavioural avoidance Probable VL VL

Masking sound and communication Probable VL VL

Indirect impacts on food sources Probable VL VL

Mysticetes Cetaceans Physiological injury Probable M - H L

Behavioural avoidance Probable M - H L

Masking sound and communication Probable M L





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(with mitigation)

Significance

Without

mitigation

With

mitigation

Odontocetes Cetaceans Physiological injury Probable M - H L

Behavioural avoidance Probable VL - L VL



Impact on other users of the sea:

Fishing industry Demersal trawl Highly probable L L

Mid-water trawl Improbable M M

Deep-sea trawl Improbable NO IMPACT

Small pelagic purse-seine Improbable VL VL

Large pelagic long-line Highly probable M M

Demersal long-line Highly probable VL VL

Tuna pole Improbable NO IMPACT

Traditional line-fish Improbable NO IMPACT

Deep-sea crab Improbable M M

Rock lobster Improbable NO IMPACT

Fisheries

research

Demersal Probable VL VL

Acoustic Probable M L

Marine transport routes Highly probable L VL

Marine mining and

exploration

Marine mining Improbable NO IMPACT

Oil and gas exploration Improbable L VL

H=High M=Medium L=Low VL=Very low Insig. = Insignificant N/A=Not

applicable

All impacts

are negative

6. RECOMMENDATIONS

6.1 COMPLIANCE WITH ENVIRONMENTAL MANAGEMENT PROGRAMME AND MARPOL

STANDARDS

All phases of the proposed project (including pre-establishment phase, establishment phase, operational

phase, and decommissioning and closure phase) must comply with the Environmental Management

Programme (EMP) presented in Chapter 7 of the EIA Report. In addition, the seismic and support vessels

must ensure compliance with MARPOL 73/78 standards.

6.2 SURVEY TIMING AND SCHEDULING

The seismic survey programme should be undertaken over two seasons in order to avoid the key cetacean

migration and breeding period which extends from the beginning of June to the end of November (i.e. the

survey period is from December to May). As several of the large whale species (including mother-calf pairs)

remain abundant off the northern Namibian coast during December and January, it is further recommended

that PAM technology, which detects animals through their vocalisations, in combination with thermal imaging

cameras be continuously implemented should surveying occur during this period.

It is recommended that the operator engage with the fishing industry (specifically the midwater trawl, large

pelagic long-line and dee-sea crab sectors) and MFMR (fisheries research managers) well in advance of

commencement in order to discuss their respective fishing and research survey programmes (timing and

location) in order to minimise or avoid disruptions to all parties. The possibility of undertaking concurrent

activities within the seismic survey area should be investigated.




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6.3 SEISMIC SURVEY PROCEDURES

6.3.1 PAM technology

PAM technology, which detects animals through their vocalisations, must be implemented when surveying at

night or during adverse weather conditions and thick fog. In addition, PAM technology must be implemented

continuously during survey operations if surveying is undertaken in December and January.

The PAM hydrophone streamer should ideally be towed behind the airgun array to minimise the interference

of vessel noise, and be fitted with two hydrophones to allow directional detection of cetaceans. In order to

avoid unnecessary delays to the survey programme, it is recommended that a spare PAM cable and sensor

are kept on-board should there be any technical problems with the system. However, if there is a technical

problem with PAM during surveying, visual watches must be maintained by the Marine Mammal Observer

(MMO) during the day and thermal imaging cameras must be used at night while PAM is being repaired.

6.3.2 Thermal imaging cameras

If surveying is undertaken in December and January, survey vessels should also be fitted with thermal

imaging cameras, which use infrared technology to detect the heat contrast between the marine mammal

and the ocean. Advanced camera systems are capable of simultaneously monitoring 360° around a vessel

and are capable of detecting smaller odontocetes at distances of several 100 m, while blows from large

baleen whales can be seen at distances of up several kilometres. The infrared camera system offers

observations possibilities at night, improved detection during daylight hours, and also allows precise

measurement of the distance of the marine mammal to the seismic vessel.

6.3.3 “Soft-start” procedure, pre-watch period and airgun firing

All initiations of seismic surveys must be carried out as “soft-starts” for a minimum of 20 minutes. This

requires that the sound source be ramped from low to full power rather than initiated at full power, thus

allowing a flight response by marine fauna to outside the zone of injury or avoidance. Where possible, “soft-

starts” should be planned so that they commence within daylight hours.

“Soft-start” procedures must only commence once it has been confirmed for a 30-minute period1 that there is

no seabird (diving), turtle or marine mammal activity within 500 m of the vessel. However, in the case of

seals and small cetaceans (< 3 m in overall length), which are often attracted to survey vessels, the normal

“soft-start” procedures should be allowed to commence, if after a period of 30 minutes seals and small

cetaceans are still within 500 m of the airguns.

All breaks in airgun firing of longer than 20 minutes must be followed by a pre-shoot watch (as described

above) and a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks of

shorter than 20 minutes should be followed by a visual assessment for marine mammals within the 500 m

mitigation zone (not a pre-shoot watch) and a “soft-start” of similar duration.

1 The pre-watch survey methodology differs depending on when the survey is undertaken:

• Dec to end Jan: visually and PAM technology during the day and using PAM and Infra-red technology at night or during periods

of poor daytime visibility.

• Feb to end May: visually during the day and using PAM technology at night or during periods of poor daytime visibility.




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The use of the lowest practicable airgun volume, as defined by the operator, should be defined and enforced.

During surveying, airgun firing should be terminated when:

• obvious negative changes to turtle, seal and cetacean behaviour is observed;

• turtles or cetaceans are observed within 500 m of the operating airgun and appear to be approaching

the firing airgun; or

• there is mass mortality of fish or mortality / injuries to seabirds, turtles, seals or cetaceans as a direct

result of the survey.

The survey should remain terminated until such time that the time MMO confirms that:

• Turtles or cetaceans have moved to a point that is more than 500 m from the source;

• Despite continuous observation, 30 minutes has elapsed since the last sighting of the turtles or

cetaceans within 500 m of the source; and

• Risks to seabirds, turtles, seals or cetaceans have been significantly reduced.

A log of all termination decisions must be kept (for inclusion in both daily and “close-out” reports).

6.3.4 MMO and PAM operator

An independent on-board MMO and, where necessary, a PAM operator must be appointed for the duration

of the seismic survey. They must have experience in seabird, turtle and marine mammal identification and

observation techniques. The duties of the MMO would be to:

Marine fauna:

• Confirm that there is no marine faunal activity within 500 m of the seismic source array prior to

commencing with the “soft-start” procedures;

• Monitor marine faunal activity during daytime surveying;

• Observe and record responses of marine fauna to the seismic survey, including seabird, turtle, seal

and cetacean incidence and behaviour and any mortality or injuries of marine fauna as a result of the

seismic survey. Data capture should include species identification, position (latitude/longitude),

distance from the vessel, swimming speed and direction (if applicable) and any obvious changes in

behaviour (e.g. startle responses or changes in surfacing/diving frequencies, breathing patterns) as a

result of the survey activities;

• Record survey activities, including sound levels, “soft-start” procedures and survey periods (duration);

and

• Request the temporary termination of the seismic survey, as appropriate. It is important that the

MMOs’ decisions to terminate firing are made confidently and expediently;

Other:

• Record meteorological conditions;

• Monitor compliance with international marine pollution regulations (MARPOL 73/78 standards); and

• Prepare daily reports of all observations. These reports should be forwarded to the key stakeholders,

as appropriate.

The duties of the PAM operator would be to:

• Ensure that hydrophone streamers are optimally placed within the towed array;

• Confirm that there is no marine mammal activity within 500 m of the vessel prior to commencing with

the “soft-start” procedures at night or during periods of poor daytime visibility, as well as continuously

during survey operations if surveying is undertaken in December and January;




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• Monitor marine cetacean activity during night time surveying or during periods of poor daytime

visibility;

• Record species identification, position (latitude/longitude) and distance from the vessel, where

possible;


and

• Request the temporary termination of the seismic survey, as appropriate.

All data recorded by the MMO and PAM operator should form part of the survey “close-out” report.

6.4 OTHER MITIGATION MEASURES

Other mitigation measures that should also be implemented during the survey in order to ensure that any

potential impacts are minimised include the following:

Equipment

• ‘Turtle-friendly’ tail buoys should be used by the survey contractor or existing tail buoys should be

fitted with either exclusion or deflector 'turtle guards'.

Vessel safety

• The survey vessel must be certified for seaworthiness through an appropriate internationally

recognised marine certification programme (e.g. Lloyds Register, Det Norske Veritas). The

certification, as well as existing safety standards, requires that safety precautions would be taken to

minimise the possibility of an offshore accident;

• Collision prevention equipment should include radar, multi-frequency radio, foghorns, etc. Additional

precautions include:

> A support / chase vessel with an on-board FLO familiar with the fisheries expected in the area;

> The existence of an internationally agreed 500 m safety zone around the survey vessel;

> Cautionary notices to mariners; and

> Access to current weather service information.

• The vessels are required to fly standard flags, lights (three all-round lights in a vertical line, with the

highest and lowest lights being red and the middle light being white) or shapes (three shapes in a

vertical line, with the highest and lowest lights being balls and the middle light being a diamond) to

indicate that they are engaged in towing surveys and are restricted in manoeuvrability, and must be

fully illuminated during twilight and night;

• Report any emergency situation to the Commissioner for Petroleum Affairs;

Vessel lighting

• Lighting on-board survey vessels should be reduced to the minimum safety levels to minimise

stranding of pelagic seabirds on the survey vessels at night. All stranded seabirds must be retrieved

and released during daylight hours;

Emissions, discharges into the sea and solid waste

• Ensure adequate maintenance of diesel motors and generators to minimise the volume of soot and

unburned diesel released to the atmosphere;

• Route deck and machinery space drainage to a separate drainage system (oily water catchment

system) for treatment to ensure compliance with MARPOL (15 ppm);

• Ensure all process areas are bunded to ensure drainage water flows into the closed drainage system;




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• Use drip trays to collect run-off from equipment that is not contained within a bunded area and route

contents to the closed drainage system;

• Use of low toxicity, biodegradable detergents during deck cleaning to further minimise the potential

impact of deck drainage on the marine environment;

• Ensure adequate maintenance of all hydraulic systems and frequent inspection of hydraulic hoses;

• Undertake spill management training and awareness of crew members of the need for thorough clean-

up of any spillages immediately after they occur, as this would minimise the volume of contaminants

washing off decks;

• Effluent discharge (e.g. sewage and galley waste as per MARPOL requirements) into the sea should

occur as far as possible from the coast;

• Initiate an on-board waste minimisation system;

• Ensure on-board solid waste storage is secure;

• Ensure that waste (solid and hazardous) disposal onshore is carried out in accordance with the

appropriate laws and ordinances;

• Prepare a project specific Emergency Response Plan and Shipboard Oil Pollution Emergency Plan for

the proposed seismic survey, which defines the organisational structure and protocols that would be

implemented to respond to any incident (including accidental oil / fuel spills) in a safe, rapid, effective

and efficient manner. These plans should be submitted to MME for information purposes as part of

their formal notification prior to survey commencement;

• An application for the transfer of oil at sea (outside a harbour but within 50 nm of the Namibian coast)

must be submitted to the Minister, via the Permanent Secretary, at least two weeks prior to the

proposed date of transfer;

• Not less than 24 hours prior to the commencement of the transfer operation the Permanent Secretary

must be informed, in writing, that the ship is, and will be kept, in a fit state to undertake the transfer

operation and to contend with any emergencies that may arise;

• Offshore bunkering should not be undertaken in the following circumstances:

> Wind force and sea state conditions of 6 or above on the Beaufort Wind Scale;

> During any workboat or mobilisation boat operations;

> During helicopter operations;

> During the transfer of in-sea equipment; and

> At night or times of low visibility.

• Support vessels must have the necessary spill response capability to deal with accidental spills in a

safe, rapid, effective and efficient manner;

• In the event of an oil spill that poses a risk of major harm to the environment immediately notify

NAMPORT and the Commissioner for Petroleum Affairs;

Communication with key stakeholders

• Prior to commencement, the following key stakeholders should also be consulted and informed of the

proposed survey activity (including navigational coordinates of the survey area, timing and duration the

proposed activities) and the likely implications thereof (500 m safety zone and proposed safe

operational limits):

> Fishing industry / associations:

- Association of Namibian Fishing Industries;

- Namibian Hake Association;

- Namibian Monk and Sole Association;

- Midwater Trawling Association of Namibia;

- Namibian Tuna and Hake Long-lining Association;

- Pelagic Fishing Association; and

- Namibian Crab Association.




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> Other:

- MME

- MET;

- MFMR;

- Directorate of Maritime Affairs;

- Monitoring, Control and Surveillance Unit in Walvis Bay (Vessel Monitoring System in

particular);

- Namibian Ports Authority;

- Port captains;

- South African Navy Hydrographic office; and

- Overlapping and neighbouring prospecting / exploration right holders.

• The operator must formally notify the MME (Commissioner for Petroleum Affairs2)

of the survey

location, commencement date and anticipated duration of the seismic survey prior to commencement;

• The operator must request, in writing, that the South African Navy Hydrographic office release a

Coastal Navigational Warnings for the duration of the seismic survey period and that daily notifications

be issued by Walvis Bay Radio. The notifications should give notice of (1) the co-ordinates of the

proposed survey area, (2) an indication of the proposed survey timeframes and day-to-day location of

the survey vessel(s), and (3) an indication of the 500 m safety zones and the proposed safe

operational limits of the survey vessel(s);

• An independent on-board FLO, who is familiar with fishery operations in the area, must be appointed

for the duration of the survey. The duties of the FLO would be to:

> Identify fishing vessels active in the area and associated fishing gear;

> Advise on actions to be taken in the event of encountering fishing gear;

> Provide back-up on-board facilitation with the fishing industry and other users of the sea. This

would include communication with fishing and shipping / sailing vessels in the area in order to

reduce the risk of interaction between the proposed survey and other existing or proposed

activities; and

> Provide daily electronic reporting on vessel activity and recording of any communication and/or

interaction should be undertaken in order to keep key stakeholders informed of survey activity

and progress.

• Ongoing notification is to be undertaken throughout the duration of survey with the submission of daily

reports (via email) indicating the vessel’s location to key stakeholders, as appropriate;

• Surveying should avoid diamond mining vessels, unless prior arrangements have been made with the

operator; and

• Marine mammal incidence data and seismic source output data arising from the survey should be

made available, if requested, to the MFMR, MME, NAMCOR and the Namibian Dolphin Project to

inform studies of cetacean distribution and timing off the Namibian coast.

Helicopter operations

• All flight paths should be planned to avoid seal colonies between Walvis Bay and the survey area

(including Cape Cross, Möwe Bay and Cape Frio) and seabird colonies in Walvis Bay, Swakopmund

and Cape Cross, as well as the Kunene River mouth and estuary, by at least 1 852 m (i.e. 1 nm);

• Extensive coastal flights (parallel to the coast within 1 nautical mile of the shore) should be avoided;

and

• All pilots must be briefed on ecological risks associated with over flights of seabird and seal colonies.

2 The Commissioner is obliged to notify all relevant parties and cause such offshore location to be published in a “Notice to Mariners” (in

terms of Regulation 15(b) of the Petroleum (Exploration and Production) Act No. 2 of 1991), as published by the South African Navy

Hydrographic office in Cape Town.




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PROPOSED 3D SEISMIC SURVEY IN THE WALVIS BASIN

OFF THE COAST OF SOUTHERN NAMIBIA

TABLE OF CONTENTS

DOCUMENT INFORMATION .............................................................................................................................. i

EXPERTISE OF ENVIRONMENTAL ASSESSMENT PRACTITIONER ........................................................... iii

EXECUTIVE SUMMARY .................................................................................................................................... v

TABLE OF CONTENTS .................................................................................................................................. xxiii

1. INTRODUCTION .................................................................................................................................. 1-1

1.1 PROJECT BACKGROUND ........................................................................................................ 1-1

1.2 PURPOSE AND GOALS OF THE EIA AND EIA REPORT ....................................................... 1-1

1.3 STRUCTURE OF THIS REPORT .............................................................................................. 1-3

2. EIA APPROACH AND METHODOLOGY ............................................................................................ 2-1

2.1 KEY LEGISLATIVE REQUIREMENTS ...................................................................................... 2-1

2.1.1 Introduction ................................................................................................................. 2-1

2.1.2 Petroleum (Exploration and Production) Act, 1991 .................................................... 2-1

2.1.3 Environmental Assessment Policy, 1995 ................................................................... 2-2

2.1.4 Environmental Management Act, 2007 ...................................................................... 2-2

2.1.5 Other legislation .......................................................................................................... 2-3

2.2 EIA PROCESS ........................................................................................................................... 2-5

2.2.1 Assumptions and limitations ....................................................................................... 2-5

2.2.2 EIA project team ......................................................................................................... 2-5

2.2.3 Specialist Studies ....................................................................................................... 2-6

2.2.4 Compilation and review of EIA Report ........................................................................ 2-6

3. PROJECT DESCRIPTION ................................................................................................................... 3-1

3.1 GENERAL INFORMATION ........................................................................................................ 3-1

3.1.1 Operator ...................................................................................................................... 3-1

3.1.2 Existing exploration / production right holders ............................................................ 3-1

3.1.3 Monitoring and EMP performance assessment.......................................................... 3-2

3.1.4 Emergency plans ........................................................................................................ 3-2

3.2 TYPICAL SEISMIC SURVEYS .................................................................................................. 3-2

3.2.1 Introduction ................................................................................................................. 3-2

3.2.2 Survey methodology and airgun array ........................................................................ 3-3

3.2.3 Sound pressure emission levels ................................................................................. 3-4

3.2.4 Recording equipment .................................................................................................. 3-5

3.2.5 Exclusion zone ............................................................................................................ 3-5

3.3 DETAILED SEISMIC SURVEY SPECIFICATIONS ................................................................... 3-6

3.3.1 Seismic survey programme ........................................................................................ 3-6

3.3.2 Seismic contractor ...................................................................................................... 3-6

3.3.3 Seismic survey vessel ................................................................................................ 3-6

3.3.4 Anticipated airgun and hydrophone array specifications ............................................ 3-7

3.3.5 Support Services ........................................................................................................ 3-7




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4. DESCRIPTION OF THE AFFECTED ENVIRONMENT ....................................................................... 4-1

4.1 GEOPHYSICAL CHARACTERISTICS ...................................................................................... 4-1

4.1.1 Bathymetry .................................................................................................................. 4-1

4.1.2 Coastal and inner-shelf geology and seabed geomorphology bathymetry ................ 4-1

4.2. BIOPHYSICAL CHARACTERISTICS ........................................................................................ 4-3

4.2.1 Climate ........................................................................................................................ 4-3

4.2.2 Large-scale circulation and coastal currents .............................................................. 4-5

4.2.3 Tides ........................................................................................................................... 4-8

4.2.4 Waves ......................................................................................................................... 4-8

4.2.5 Turbidity .................................................................................................................... 4-10

4.2.6 Organic inputs ........................................................................................................... 4-11

4.2.7 Low oxygen events ................................................................................................... 4-12

4.2.8 Sulphur eruptions ...................................................................................................... 4-12

4.3 BIOLOGICAL OCEANOGRAPHY............................................................................................ 4-13

4.3.1 Offshore benthic communities .................................................................................. 4-14

4.3.1.1 Benthic invertebrate macro fauna ............................................................. 4-14

4.3.1.2 Deep-water coral communities, seamount communities and

Vulnerable Marine Ecosystems ................................................................. 4-16

4.3.2 Plankton .................................................................................................................... 4-17

4.3.3 Jellyfish ..................................................................................................................... 4-17

4.3.4 Cephalopods ............................................................................................................. 4-18

4.3.5 Fish ........................................................................................................................... 4-19

4.3.5.1 Pelagic fish ................................................................................................ 4-19

4.3.5.2 Demersal fish............................................................................................. 4-20

4.3.6 Seabirds .................................................................................................................... 4-21

4.3.7 Turtles ....................................................................................................................... 4-23

4.3.8 Marine mammals ...................................................................................................... 4-24

4.3.8.1 Cetaceans ................................................................................................. 4-24

4.3.8.2 Pinnipeds ................................................................................................... 4-31

4.4 SOCIO-ECONOMIC ENVIRONMENT ..................................................................................... 4-32

4.4.1 Fisheries ................................................................................................................... 4-33

4.4.1.1 Overview of fisheries ................................................................................. 4-33

4.4.1.2 Demersal trawl .......................................................................................... 4-34

4.4.1.3 Mid-water trawl .......................................................................................... 4-36

4.4.1.4 Deep-water trawl ....................................................................................... 4-38

4.4.1.5 Small pelagic purse-seine ......................................................................... 4-38

4.4.1.6 Large pelagic long-line .............................................................................. 4-40

4.4.1.7 Demersal long-line .................................................................................... 4-42

4.4.1.8 Tuna pole................................................................................................... 4-44

4.4.1.9 Line-fish ..................................................................................................... 4-47

4.4.1.10 Deep-sea crab ........................................................................................... 4-48

4.4.1.11 Rock lobster............................................................................................... 4-48

4.4.1.12 Fisheries research ..................................................................................... 4-49

4.4.2 Shipping transport ..................................................................................................... 4-50

4.4.3 Prospecting and mining ........................................................................................... 4-51

4.4.3.1 Oil and gas prospection and production .................................................... 4-51

4.4.3.2 Diamond prospecting and mining .............................................................. 4-51

4.4.3.3 Prospecting and mining of other minerals ................................................. 4-52

4.4.4 Recreational utilisation .............................................................................................. 4-53




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4.4.5 Other human utilisation ............................................................................................. 4-53

4.4.5.1 Undersea cables ....................................................................................... 4-53

4.4.5.2 Archaeological site .................................................................................... 4-54

4.4.5.3 Mariculture ................................................................................................. 4-54

4.4.5.4 Guano harvesting ...................................................................................... 4-55

4.4.5.5 Conservation areas and Marine Protected Areas ..................................... 4-55

5. ENVIRONMENTAL IMPACT ASSESSMENT ...................................................................................... 5-1

5.1 INTRODUCTION ........................................................................................................................ 5-1

5.2 IMPACT OF NORMAL SEISMIC/SUPPORT VESSELS AND HELICOPTER OPERATION .... 5-1

5.2.1 Emissions to the atmosphere ..................................................................................... 5-1

5.2.2 Discharges/disposal to the sea ................................................................................... 5-2

5.2.2.1 Deck drainage ............................................................................................. 5-2

5.2.2.2 Machinery space drainage .......................................................................... 5-3

5.2.2.3 Sewage ........................................................................................................ 5-4

5.2.2.4 Galley waste ................................................................................................ 5-4

5.2.2.5 Solid waste .................................................................................................. 5-5

5.2.2.6 Accidental oil spill during bunkering / refuelling .......................................... 5-6

5.2.3 Noise from vessel and helicopter operations .............................................................. 5-7

5.2.3.1 Noise from seismic and support vessel operations ..................................... 5-7

5.2.3.2 Noise from helicopter operations................................................................. 5-7

5.3 IMPACT OF SEISMIC NOISE ON MARINE FAUNA ................................................................. 5-9

5.3.1 Potential impacts on plankton species ....................................................................... 5-9

5.3.2 Potential impacts to marine invertebrates ................................................................ 5-10

5.3.3 Potential impacts on fish ........................................................................................... 5-11

5.3.4 Potential impacts on seabirds ................................................................................... 5-14

5.3.5 Potential impacts on turtles....................................................................................... 5-16

5.3.6 Potential impacts on seals ........................................................................................ 5-18

5.3.7 Potential impact on cetaceans (whales and dolphins) ............................................. 5-20

5.4 IMPACT ON OTHER USERS OF THE SEA ............................................................................ 5-24

5.4.1 Potential impact on fishing industry .......................................................................... 5-24

5.4.1.1 Potential impact on fishing sectors ............................................................ 4-24

5.4.1.2 Potential impact on fisheries research ...................................................... 4-29

5.4.2 Potential impact on marine transport routes ............................................................. 5-30

5.4.3 Potential impact on marine mining ........................................................................... 5-31

5.4.4 Potential impact on oil and gas exploration .............................................................. 5-32

6. CONCLUSIONS AND RECOMMENDATIONS .................................................................................... 6-1

6.1 CONCLUSIONS ......................................................................................................................... 6-1

6.2 RECOMMENDATIONS .............................................................................................................. 6-4

6.2.1 Compliance with EMP and MARPOL standards ........................................................ 6-4

6.2.2 Survey timing and scheduling ..................................................................................... 6-4

6.2.3 Seismic survey procedures ......................................................................................... 6-4

6.2.3.1 PAM technology .......................................................................................... 6-4

6.2.3.2 Thermal imaging cameras ........................................................................... 6-4

6.2.3.3 “Soft-start” procedure, pre-watch period and airgun firing .......................... 6-5

6.2.3.4 MMO and PAM operator ............................................................................. 6-6

6.2.4 Other mitigation measures .......................................................................................... 6-6

6.2.4.1 Equipment ................................................................................................... 6-7

6.2.4.2 Vessel safety ............................................................................................... 6-7

6.2.4.3 Vessel lighting ............................................................................................. 6-7

6.2.4.4 Emissions, discharges into the sea and solid waste ................................... 6-7




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6.2.4.5 Communication with key stakeholders ........................................................ 6-8

6.2.4.6 Helicopter operations .................................................................................. 6-9

7. ENVIRONMENTAL MANAGEMENT PROGRAMME .......................................................................... 7-1

7.1 PLANNING PHASE .................................................................................................................... 7-2

7.2 ESTABLISHMENT PHASE ........................................................................................................ 7-5

7.3 OPERATIONAL PHASE ............................................................................................................ 7-6

7.4 DECOMMISSIONING AND CLOSURE PHASE ...................................................................... 7-16

8. REFERENCES ..................................................................................................................................... 8-1

LIST OF APPENDICES

Appendix 1: Convention for assigning significance ratings to impacts

Appendix 2: Fisheries Assessment

Appendix 3: Marine Faunal Assessment

Appendix 4: I&AP database

Appendix 5 Vessel specifications

LIST OF FIGURES

Figure 1.1: Location of the proposed 3D survey area in the Namibe Basin off the coast of northern

Namibia (after Spectrum, January 2017) .............................................................................. 1-2

Figure 3.1: Principles of offshore seismic acquisition surveys (from fishsafe.eu) ................................... 3-3

Figure 3.2: Typical configuration and safe operational limits for 3D seismic survey operations. ........... 3-4

Figure 3.3: A typical pressure signature produced on firing of an airgun. .............................................. 3-5

Figure 4.1: Bathymetry of the continental margin off Namibia and south-western South Africa.

From Rogers and Bremner (1991). Approximate location of the survey area is also

shown. ................................................................................................................................... 4-2

Figure 4.2: The proposed survey area and lines in relation to the sediment distribution on the

continental shelf off northern Namibian (Adapted from Rogers 1977). ................................ 4-3

Figure 4.3: Fog day frequency for 1984 using Meteosat Images (Adapted from Olivier 1992, 1995) .... 4-4

Figure 4.4: Seasonal wind roses for Pelican Point (Source PRDW 2008). ............................................ 4-6

Figure 4.5: Map of the south-east Atlantic showing surface and near-surface currents, frontal

zones, upwelling cells, major areas of freshwater input and bathymetry (re-drawn from

Shannon & Nelson 1996). Approximate location of the survey area is also shown. ........... 4-7

Figure 4.6: Upwelling centres on the West Coast of Namibia (Adapted from Shannon 1985).

Approximate location of the survey area and lines is also shown. ....................................... 4-9

Figure 4.7: Seasonal offshore wave conditions for a data point located at 23° S, 13.75°E (CSIR

2009) ................................................................................................................................... 4-10

Figure 4.8: The proposed survey area in relation to major spawning areas in the central and

northern Benguela region (adapted from Cruikshank 1990; Hampton 1992) ..................... 4-18

Figure 4.9: The survey area (red polygon) in relation to the post-nesting distribution of nine

satellite tagged leatherback females (1996 – 2006; Oceans and Coast, unpublished

data) .................................................................................................................................... 4-23

Figure 4.10: Project - environment interaction points in central Namibia, illustrating conservation

areas, seal colonies and seabird breeding areas in the coastal region. Location of the

survey area is also shown .................................................................................................. 4-32

Figure 4.11: Survey area in relation to hake-directed demersal trawl catch (1992 – 2010) off the

Namibian coast. .................................................................................................................. 4-35




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Figure 4.12: The average number of trawls expended on a monthly basis by the demersal trawl

fleet nationally and within the proposed survey area (2004 – 2010) .................................. 4-35

Figure 4.13: Schematic diagram of trawl gear typically used by the Namibian hake trawl vessels ........ 4-36

Figure 4.14: Survey area in relation to horse mackerel mid-water trawl catch (1997 – 2011) off the

Namibian coast. .................................................................................................................. 4-37

Figure 4.15: The average monthly catch of horse mackerel taken nationally and from the proposed

survey area (2004 – 2011) .................................................................................................. 4-37

Figure 4.16: Mid-water trawl gear configuration ...................................................................................... 4-38

Figure 4.17: Survey area in relation to catch positions and Quota Management Areas of the deep-

water trawl fishery targeting orange roughy (1994 to 2007). Note that the fishery is

currently closed ................................................................................................................... 4-39

Figure 4.18: Survey area in relation to small pelagic purse-seine catch (1996 – 2011). ........................ 4-39

Figure 4.19: Schematic of typical purse-seine gear deployed in the “small” pelagic fishery .................. 4-40

Figure 4.20: Survey area in relation to pelagic long-line effort off the coast of Namibia (2008 - 2013) .. 4-41

Figure 4.21: Monthly average catch and effort recorded within the large pelagic long-line sector

within Namibian waters (2008 – 2013). .............................................................................. 4-42

Figure 4.22: Typical pelagic long-line gear configuration ........................................................................ 4-42

Figure 4.23: Survey area in relation to demersal long-line catch (hake) off the coast of Namibia

(2000 – 2010) ...................................................................................................................... 4-43

Figure 4.24: Average monthly catch landed by the Namibian demersal long-line fleet (2000 – 2010) .. 4-44

Figure 4.25: Typical configuration of demersal (bottom-set) hake long-line gear used in Namibian

waters .................................................................................................................................. 4-44

Figure 4.26: Average monthly catch and effort recorded by the tuna pole and line fleet in Namibian

waters (2008 – 2013) .......................................................................................................... 4-45

Figure 4.27: Survey area in relation to tuna pole and line-fish fishing effort (2009 – 2013) ................... 4-46

Figure 4.28: Schematic diagram of pole and line operation (from www.fao.org/fishery ......................... 4-46

Figure 4.29: Survey area in relation to the spatial range of ski-boats operating within the line-fish

sector along the Namibian coastline ................................................................................... 4-47

Figure 4.30 Survey area in relation to the distribution of deep-sea red crab catch within Namibian

waters (2003 – 2011) .......................................................................................................... 4-49

Figure 4.31 Survey area in relation to the station layout covered during the 2015 hake swept-area

biomass survey (with depth contours of 100, 200 and 1 000 m) ........................................ 4-50

Figure 4.32 Major shipping routes around southern Africa. The southern boundary of the survey

area is also shown (purple outline). Data from the South African Data Centre for

Oceanography (image source: CSIR) ................................................................................. 4-51

Figure 4.33 Project - environment interaction points in central and southern Namibia, illustrating

the distribution of existing industries and other users in the coastal region. The

approximate locality of the survey area is also shown........................................................ 4-52

Figure 4.34 Configuration of the current African undersea cable systems, November 2014

(From http://www.manypossibilities.net) ............................................................................. 4-54

Figure 4.35 Guano platform off the coast of Namibia between Swakopmund and Walvis Bay (ref.

https://freeassociationdesign.wordpress.com/2010/09/10/islands-and-post-peak-

guano/, 6 Feb 2017) ............................................................................................................ 4-55




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LIST OF TABLES

Table 2.1: EIA project team.................................................................................................................... 2-5

Table 3.1: List of licence blocks and associated right holders in the proposed survey area ................. 3-1

Table 3.2: Vessel specifications ............................................................................................................. 3-7

Table 3.3: Airgun and hydrophone array specifications…………………………………………….. ......... 3-7

Table 4.1: Cephalopod species of importance or potential importance within the Benguela

System. After Lipinski (1992).. ............................................................................................ 4-19

Table 4.2: Namibian breeding seabird species with their Namibian and global IUCN Red-listing

classification (from Kemper et al. 2007; Simmons & Brown in press). ............................... 4-22

Table 4.3: Other Namibian Red-listed bird species with their Namibian and global IUCN Red-

listing classification (from Kemper et al. 2007; Simmons & Brown in press) ...................... 4-22

Table 4.4: List of cetacean species known (from historic sightings or strandings) or likely (habitat

projections based on known species parameters) to occur in Namibian waters. Likely

occurrence in probable habitat (Shelf or Offshore) is indicated by ‘yes’, ‘no’ (unlikely),

‘edge’ (shelf edge 200-500 m depth) or ‘?’ (unknown) ....................................................... 4-25

Table 5.1: Impact of atmospheric emissions from the seismic and support vessels, and helicopter .... 5-2

Table 5.2: Impact of deck drainage from the seismic and support vessels. .......................................... 5-3

Table 5.3: Impact of machinery space drainage from the seismic and support vessels. ...................... 5-3

Table 5.4: Impact of sewage effluent discharge from the seismic and support vessels. ....................... 5-4

Table 5.5: Impact of galley waste disposal from the seismic and support vessels. .............................. 5-5

Table 5.6: Impact of solid waste disposal from the seismic and support vessels.................................. 5-5

Table 5.7: Impact of an accidental oil spill during bunkering operations ............................................... 5-7

Table 5.8: Impact of noise from seismic and support vessel operations ............................................... 5-7

Table 5.9: Impact of noise from helicopter operations. .......................................................................... 5-8

Table 5.10 Impact of seismic noise on plankton. .................................................................................... 5-9

Table 5.11: Impact of seismic noise on marine invertebrates ................................................................ 5-11

Table 5.12: Impact of seismic noise on fish. .......................................................................................... 5-13

Table 5.13: Impact of seismic noise on diving seabirds. ....................................................................... 5-15

Table 5.14: Impact of seismic noise on non-diving seabirds. ................................................................ 5-16

Table 5.15: Impact of seismic noise on turtles. ...................................................................................... 5-18

Table 5.16 Impact of seismic noise on seals ........................................................................................ 5-19

Table 5.17 Impact of seismic noise on mysticete cetaceans (baleen whales). .................................... 5-23

Table 5.18 Impact of seismic noise on odontocete cetaceans (toothed whales and dolphins). ........... 5-24

Table 5.19 Assessment of the potential impact on the fishing industry in the proposed survey

area. .................................................................................................................................... 5-28

Table 5.20: Assessment of the potential impact on fisheries research in the proposed survey area. ... 5-30

Table 5.21 Assessment of interference with marine transport routes .................................................. 5-31

Table 5.22: Assessment of impact on oil and gas exploration. .............................................................. 5-32

Table 6.1: Summary of the significance of potential impacts related to the proposed 3D seismic


possible and / or considered necessary, thus significance rating remains. .......................... 6-2




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ACRONYMS AND ABBREVIATIONS

A list of acronyms and abbreviations used in this report is provided below.

Acronyms /

Abbreviations Definition

2D Two-dimensional

3D Three-dimensional

ACE African Coast to Europe cable system

BENEFIT Benguela Environment Fisheries Interaction and Training

BID Background Information Document

BOD Biological oxygen demand

CITES Convention on International Trade in Endangered Species

CMS Convention on Migratory Species

CO Carbon monoxide

CO2 Carbon dioxide

COLREGS Convention on the International Regulations for Preventing Collisions at Sea

EASSy Eastern Africa Submarine Cable System

EEZ Exclusive Economic Zone

EIA Environmental Impact Assessment

EMP Environmental Management Programme

EMR Emergency Response Plan

EPLs Exclusive Prospecting Licences

FLO Fisheries Liaison Officer

GRT Gross Registered Tonnage

I&APs Interested & Affected Parties

ICCAT International Commission for the Conservation of Atlantic Tunas

IUCN International Union for Conservation of Nature

JNCC Joint Nature Conservation Commission

LUCORC Lüderitz Upwelling Cell-Orange River Cone

MARPOL International Convention for the Prevention of Pollution from Ships, 1973/1978

MET Ministry of Environment and Tourism

MFMR Ministry of Fisheries and Marine Resources

MME Ministry of Mines and Energy

MMO Marine Mammal Observer

MPA Marine Protected Area

NACOMA Namibian Coast Conservation and Management project

NAMCOR National Petroleum Corporation of Namibia

NAMPORT Namibian Port Authority

NIMPA Namibian Islands’ Marine Protected Area

nm Nautical mile

NOSCP Namibian National Oil Spill Contingency Plan

NOX Nitrogen oxides

OMZ Oxygen Minimum Zone

OPRC Oil Pollution Preparedness, Response and Co-operation

PAM Passive Acoustic Monitoring

PIM Particulate Inorganic Matter

POM Particulate Organic Matter

PTS Permanent Threshold Shifts

QMA Quota Management Area




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Page xxx

Acronyms /

Abbreviations Definition

SACS South Atlantic Cable System

SADC Southern African Development Community

SADCO Southern African Data Centre for Oceanography

SAFE South Africa Far East

SAT3 South Atlantic Telecommunications cable no.3

SLR SLR Environmental Consulting (Namibia) (Pty) Ltd

SOX Sulphur oxides

SOPEP Shipboard Oil Pollution Emergency Plan

TAC Total Allowable Catch

TAE Total Applied Effort

TSPM Total Suspended Particulate Matter

TTS Temporary Threshold Shifts

UNCLOS United Nations Law of the Sea Convention, 1982

VME Vulnerable Marine Ecosystem

VOS Voluntary Observing Ships

WACS West Africa Cable System

WASC West African Submarine Cable

SLR Environmental Consulting (Namibia) (Pty) Ltd Page 1-1



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1 INTRODUCTION

This chapter provides background to the proposed project, describes the purpose of this report, presents the

assumptions and limitations of the study, and describes the structure of the report.

1.1 PROJECT BACKGROUND

Spectrum Geo Limited (hereafter referred to as “Spectrum”) is proposing to undertake a speculative three-

dimensional (3D) seismic survey to investigate for oil and gas reserves in the Namibe Basin off the coast of

northern Namibia (see Figure 1.1). The proposed 3D seismic survey area is 12 940 km2 in extent and is

situated roughly between the Namibian - Angolan border (17º 14’ S) and 18º 08’ S.

Spectrum has applied to undertake the seismic survey under a Multi-Client Agreement with the National

Petroleum Corporation of Namibia (NAMCOR). Although a multi-client survey is not covered specifically by

the Petroleum (Exploration and Production) Act, 1991 (No. 2 of 1991), the Ministry of Mines and Energy

(MME) has indicated that the requirements are the same as for an Exploration Licence. Thus a Petroleum

Agreement must be entered into between MME and Spectrum, a requirement of which is that a study into the

baseline environmental conditions of the survey area be undertaken.

SLR Environmental Consulting (Namibia) (Pty) Ltd (SLR) has been appointed to investigate the baseline

environmental conditions in the proposed survey area and to assess the potential impacts of the proposed

seismic survey and present the findings in an Environmental Impact Assessment (EIA) Report.

1.2 PURPOSE AND GOALS OF THE EIA AND EIA REPORT

The main purpose of the EIA is to provide a study into the baseline environmental conditions of the survey

area and investigate and assess the potential environmental impacts related to the proposed seismic survey

operations. This EIA has the following specific objectives:

• To provide an opportunity for interested and affected parties (I&APs) to be involved in the EIA process;

• To ensure that all potential key environmental issues and impacts that would result from the proposed

survey are identified, described and assessed;

• To undertake specialist studies to address any potential environmental issues and impacts requiring

further investigation;

• To identify practicable mitigation measures that would reduce potential negative impacts and

enhancement measures to increase potential benefits;

• To prepare an EIA Report, including Environmental Management Plan (EMP), that will ensure

compliance with relevant standards and requirements; and

• To communicate the results of the EIA to relevant authorities.

This EIA Report presents the findings and recommendations of the EIA process and is submitted to MME for

approval in consultation with other relevant Ministries, e.g. the Ministry of Environment and Tourism (MET)

and the Ministry of Fisheries and Marine Resources (MFMR).




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Figure 1.1: Location of the proposed 3D survey area in the Namibe Basin off the coast of northern

Namibia (after Spectrum, January 2017).




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1.3 STRUCTURE OF THIS REPORT

This report consists of eight chapters and four appendices, the contents of which are outlined below.

Section Contents

Executive Summary Provides a comprehensive synopsis of the EIA Report.

Chapter 1 Introduction

Provides background to the proposed project, describes the purpose / goals of this report and

describes the structure of the report.

Chapter 2 EIA approach and methodology

Covers the key legislative requirements of the EIA and presents the assumptions and

limitations of the study, and the EIA process undertaken.

Chapter 3 Project description

Provides general information on the proposed project, a brief background description of

seismic surveys and the detailed seismic survey specifications.

Chapter 4 Description of the affected environment

Describes the existing biophysical and social environment that could be affected by the

proposed project.

Chapter 5 Impact description and assessment

Describes and assesses the potential impacts of the proposed project on the affected

environment. It also presents mitigatory measures that could be used to reduce the

significance of any negative impacts or enhance any benefits.

Chapter 6 Conclusion and recommendations

Provides conclusions to the EIA and summarises the recommendations for the proposed

project.

Chapter 7 Environmental Management Plan

Provides an Environmental Management Plan for the proposed activities.

Chapter 8 References

Provides a list of the references used in compiling this report.

Appendices

Appendix 1 Convention for assigning significance ratings to impacts

Appendix 2 Fisheries Assessment

Appendix 3 Marine Faunal Assessment

Appendix 4 Public Participation Process

Appendix 4.1: I&AP database

Appendix 4.2: I&AP notification letter

Appendix 4.3: Advertisements

Appendix 4.4: I&AP correspondence on the EIA Report

Appendix 4.5: Comments and Responses Report

Appendix 5 Vessel specifications




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2 EIA APPROACH AND METHODOLOGY

This chapter outlines the key legislative requirements applicable to the EIA and offshore petroleum

exploration and outlines the methodology and I&AP consultation process followed in the study.

2.1 KEY LEGISLATIVE REQUIREMENTS

2.1.1 INTRODUCTION

The Republic of Namibia has five tiers of law and a number of policies relevant to environmental assessment

and protection, which includes:

• The Constitution;

• Statutory law;

• Common law;

• Customary law; and

• International law.

As the main source of legislation, the Constitution of the Republic of Namibia (1990) makes provision for the

creation and enforcement of applicable legislation. In this context and in accordance with its constitution,

Namibia has passed numerous laws intended to protect the natural environment and mitigate against

adverse environmental impacts.

The key legislative requirements and guiding principles underpinning the EIA process are outlined below.

2.1.2 PETROLEUM (EXPLORATION AND PRODUCTION) ACT, 1991

The Petroleum (Exploration and Production) Act, 1991 (No. 2 of 1991) is the main legal instrument governing

rights and duties regarding oil and gas exploration in Namibia. In terms of Section 9 of this Act a licence is

required from the MME before any reconnaissance, exploration or production operations for petroleum can

be undertaken.

As indicated in Section 1.1, Spectrum is applying to undertake the seismic survey under a Multi-Client

Agreement with NAMCOR. Although a multi-client survey is not covered specifically by the Act, MME has

indicated that the requirements are the same as for an Exploration Licence (Ms Maggy Shino, Petroleum

Commissioner, MME, pers. comm; October 2016). The requirements are presented below.

Prior to the granting of an Exploration Licence, a Petroleum Agreement must be entered into between the

Minister and the potential licensee in terms of Section 13 of the Act. The Petroleum Agreement between the

Ministry and the licence holder requires that a study into the baseline environmental conditions of the survey

area be conducted before any exploration activities are undertaken within the licence block(s). This EIA

fulfils the requirements of the baseline study in terms of the Petroleum Agreement.

A seismic survey vessel falls within the definition of “offshore installation” and therefore must comply with the

provisions of the Petroleum (Exploration and Production) Act Regulations (1999). In particular, the operator

should ensure that:

• It takes all such precautions as may be necessary to, inter alia, protect the environment and natural

resources, including precautions to prevent pollution and to ensure that all persons employed or




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otherwise present with his or her consent at or in the vicinity of the installation are duly informed of

such precautions;

• Copies of these regulations are available for perusal by people employed by or performing work within

the organisation of the operator (subcontractors) and that all such people are as far as is reasonably

practicable familiar with the relevant provisions of the regulations;

• It provides funds and takes such measures as may be necessary so as to ensure the health, safety

and welfare of employees and the protection of other persons, property, the environment and natural

resources in, at or in the vicinity of such area from hazards arising from petroleum activities carried

out, and the carrying out of any EIA studies provided for in the Petroleum Agreement entered into

between the Minister and the operator;

• The installation is registered and has a certificate of fitness;

• The location of the installation is reported to the Commissioner for publication in a “Notice to

Mariners”;

• The installation is properly marked (see International Regulations for Preventing Collisions at Sea as

incorporated into the Merchant Shipping Act, 1951);

• The installation is equipped with the necessary equipment to record environmental data;

• Hazardous substances are properly transported, handled and stored;

• An Emergency Preparedness Plan is in place and updated as necessary;

• An appropriate safety zone is created and communicated to the Commissioner for publication in the

“Notice to Mariners”; and

• Any emergency situation arising is immediately communicated to the Commissioner.

2.1.3 ENVIRONMENTAL ASSESSMENT POLICY, 1995

Namibia’s Environmental Assessment Policy was published in 1995. This policy provides for the promotion

of sustainable development and economic growth while protecting the environment in the long-term.

The government recognises, amongst others, that an EIA (termed Environmental Assessment in Policy) is a

key tool to further the implementation of a sound Environmental Policy that strives to achieve Integrated

Environmental Management. EIAs are required to ensure that the consequences of development projects

are considered and incorporated into the planning process. Marine petroleum exploration is listed in the

policy as an activity that requires an EIA. This EIA aims to fulfil the requirements of this Policy.

The Policy provides that once a project has been approved, the proponent (both private enterprise and

government) shall enter into a binding agreement based on the procedures and recommendations contained

in the EIA to ensure that the mitigatory measures recommended in the EIA, and accepted by all parties, are

complied with. This agreement should address the construction, operational and decommissioning phases,

as well as monitoring and auditing.

2.1.4 ENVIRONMENTAL MANAGEMENT ACT, 2007

The Environmental Management Act, 2007 (No. 7 of 2007) was promulgated in December 2007 and came

into effect on 6 February 2012. The main objectives of this Act are to ensure that:

• Significant effects of activities on the environment are considered carefully and timeously;

• There are opportunities for timeous participation by I&APs throughout the assessment process; and

• Findings are taken into account before any decision is made in respect of activities.




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Section 3(2) of the Act provides a set of principles which give effect to the provisions of the Constitution for

integrated environmental management. Decision makers must take these principles into account when

deciding whether or not to approve a proposed project. This Act stipulates that no party, whether private or

governmental, can conduct a listed activity without an Environmental Clearance Certificate obtained from the

Environmental Commissioner.

The EIA Regulations promulgated on 6 February 2012 in terms of Section 56 of the Environmental

Management Act, 2007, and published in Government Notice (GN) No. 30, provide for the control of certain

listed activities. These activities are listed in GN No. 29 and are prohibited until an Environmental Clearance

Certificate has been obtained from MET. Such Environmental Clearance Certificates, which may be granted

subject to conditions, will only be considered once there has been compliance with the EIA Regulations.

GN No. 30 sets out the procedures and documentation that need to be complied with in undertaking an EIA.

The undertaking of an offshore seismic survey is not included under this list and thus does not require an

Environmental Clearance Certificate in terms of the Act. The current EIA is still, however, being undertaken

in terms of the provisions of the Environmental Assessment Policy (1995), as well as the relevant provisions

of sectoral mining and exploration legislation.

2.1.5 OTHER LEGISLATION

Other legislation, policies, conventions and regional agreements applicable to offshore seismic surveys in

Namibian waters include:

Domestic Legislation:

• Atmospheric Pollution Prevention Ordinance, 1976 (No. 11 of 1976);

• Air Services Act, 1949 (No. 51 of 1949);

• Aviation Act, 1962 (No. 74 of 1962);

• Dumping at Sea Control Act, 1980 (No. 73 of 1980);

• Employee’s Compensation Act, 1941 (No. 30 of 1941);

• Foreign Investment Act, 1990 (No. 27 of 1990);

• Hazardous Substances Ordinance, 1974 (No. 14 of 1974);

• International Convention for the Prevention of Pollution from Ships Act, 1986 (No. 2 of 1986);

• International Convention relating to Intervention on the High Seas in cases of Oil Pollution Casualties

Act, 1987 (No. 64 of 1987);

• Labour Act, 2007 (No. 11 of 2007);

• Marine Resources Act, 2000 (No. 27 of 2000) (and accompanying regulations);

• Marine Traffic Act, 1981 (No. 2 of 1981) (as amended by the Marine Traffic Amendment Act, 1991 No.

15 of 1991);

• Merchant Shipping Act, 1951 (No. 57 of 1951);

• Namibian Civil Aviation Regulations 2001;

• Namibian Ports Authority Act, 1994 (No. 2 of 1994) and Port Regulations;

• National Heritage Act, 2004 (No. 27 of 2004);

• National Monuments Act, 1969 (No. 28 of 1969);

• Nature Conservation Amendment Act, 1996 (No. 5 of 1996);

• Nature Conservation Ordinance, 1975 (No. 4 of 1975);

• Petroleum Products and Energy Act, 1990 (No. 13 of 1990) (and relevant regulations);

• Petroleum Laws Amendment Act, 1998 (No. 24 of 1998);

• Petroleum (Taxation) Act, 1991 (No. 3 of 1991);




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• Prevention and Combating of Pollution of the Sea by Oil Act, 1981 (No. 6 of 1981) (as amended by Act

No. 24 of 1991) and associated Regulations;

• Territorial Sea and Exclusive Economic Zone of Namibia Act, 1990 (No. 3 of 1990);

• Water Act, 1956 (No. 54 of 1956);

• Water Resources Management Act, 2004 (No. 24 of 2004);

• Wreck and Salvage Act, 2004 (No. 4 of 2004);

Domestic Policies:

• General Environmental Assessment Guidelines for Mining (Onshore and Offshore) Sector of Namibia;

• Minerals Policy of Namibia, 2003;

• National Environmental Health Policy, 2002;

• Policy for the Conservation of Biotic Diversity and Habitat Protection, 1994;

International Conventions:

• Convention on Biological Diversity, 1992;

• Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972);

• Convention of the International Maritime Organisation, 1948;

• Convention on Civil Liability for Oil Pollution Damage, 1969;

• Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, 1972

(London Convention) and 1996 Protocol;

• Convention on Wetlands of International Importance, especially as Waterfowl Habitat, 1971;

• International Convention for the Prevention of Pollution from Ships, 197, as modified by the Protocol of

1978 (MARPOL 73/78);

• International Convention for the Safety of Life at Sea, 1974 (SOLAS) with its protocol of 1978;

• International Convention on Civil Liability for Oil Pollution Damage (CLC), 1969;

• International Convention on the establishment of an International Fund for Compensation for Oil

Pollution Damage (The Fund Convention), 1971;

• International Convention on Oil Pollution Preparedness, Response and Co-operation, 1990 (OPRC

Convention);

• International Convention relating to Intervention on the High Seas in case of Oil Pollution Casualties

(1969) and Protocol on the Intervention on the High Seas in Cases of Marine Pollution by substances

other than oil (1973);

• Kyoto Protocol on the Framework Convention on Climate Change, 1998;

• Montreal Protocol on Substances that Delete the Ozone Layer, 1987;

• United Nations Framework Convention on Climate Change, 1992;

• United Nations Law of the Sea Convention, 1982, (UNCLOS);

• Vienna Convention for the Protection of the Ozone Layer, 1985;

Regional Agreements:

• SADC Environmental Policy and Regulatory Framework for Mining, 2001;

• SADC Protocol on Mining, 1997; and

• International Industry Guidelines.




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2.2 EIA PROCESS

2.2.1 ASSUMPTIONS AND LIMITATIONS

The study assumptions and limitations are listed below:

• The study assumes that SLR has been provided with all relevant project description information by

Spectrum and that it was correct and valid at the time it was provided;

• There will be no significant changes to the project description or surrounding environment between the

completion of the report and implementation of the proposed project that could substantially influence

findings, recommendations with respect to mitigation and management, etc.;

• The assessment is based, to a large extent, on a generic description of 3D seismic surveys and on an

indicative survey layout. The assessment has, however, taken the fact that the final survey layout may

change slightly into consideration;

• The study assumes that all mitigatory measures incorporated into the project description would be

implemented as proposed; and

• Specialists were provided with all the relevant information in order to produce accurate and unbiased

assessments.

These assumptions and limitations are not considered to have any negative implications in terms of the

results of the EIA process or the required management actions included in the EMP.

2.2.2 EIA PROJECT TEAM

The EIA project team and specialists appointed to undertake the EIA process is presented in Table 2.1.

Table 2.1: EIA Project Team.

Company Name Qualifications Experience

(years) Tasks and roles

SLR

Mr Jonathan

Crowther

M.Sc. (Env. Sci.).

University of Cape Town 29

Project Director - Report review and

quality control

Mr Jeremy

Blood

M.Sc. (Cons. Ecol.),

University of

Stellenbosch

17

Project Manager (EIA) - Project

Manager (Public Participation) -

Management of the EIA process,

including process review, specialist

study review and report compilation

Mr Werner

Petrick

M. Env Mgt

(Potchefstroom

University); B. Eng

(University of Pretoria)

19 Reviewer - Report review and quality

control

Mr Marvin

Sanzila

B.Sc. Nat Res (University

of Namibia) 7

Management of the public

participation process, including I&AP

notification and assimilation of

comments

Pisces

Environmental

Services

Dr Andrea

Pulfrich

PhD (Fisheries Biology),

Christian-Albrechts

University, Kiel, Germany

22 Marine faunal assessment

Capricorn Marine

Environmental

Mr Dave

Japp

M.Sc. (Ichthyology and

Fisheries Science),

Rhodes University

29

Fisheries assessment

Ms Sarah

Wilkinson

B.Sc. (Hons) (Botany),

University of Cape Town 14




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2.2.3 SPECIALIST STUDIES

Two specialist studies were undertaken to address the issues that required further investigation, namely the

impact on fishing and marine fauna. The specialists and their details are provided in Table 2.1.

Specialist studies involved the gathering of data relevant to identifying and assessing environmental impacts

that may occur as a result of the proposed project. These impacts were then assessed according to

pre-defined rating scales (see Appendix 1). Specialists also recommended appropriate mitigation / control or

optimisation measures to minimise potential negative impacts or enhance potential benefits, respectively.

The Fisheries Assessment and Marine Faunal Assessment are attached as Appendix 2 and 3, respectively.

2.2.4 COMPILATION AND REVIEW OF EIA REPORT

The findings of the specialist studies and other relevant generic information obtained from previous studies

and seismic survey “close-out” reports have been integrated into this report. This report, therefore, contains

the key information from each of the specialist studies, including the description and assessment of impacts.

Each impact is described and assessed in terms of the nature of the effect, duration, extent, intensity and

significance level, which is assigned according to pre-defined rating scales (see Appendix 1).

This report has also been informed by comments received from I&APs on a draft version of this report.

The draft report was distributed for a 30-day comment period from 7 August to 7 September 2017 in order to

provide authorities and I&APs with an opportunity to comment on any aspect of the proposed project and the

findings of the EIA process. Steps undertaken as part of the EIA Report review process are summarised

below.

• A preliminary I&AP database of authorities, Non-Governmental Organisations, Community-based

Organisations and other key stakeholders was compiled using databases of previous studies

undertaken in area. Additional I&APs were added to the database based on responses to the

advertisements and comments received during the review process. To date 165 I&APs have been

registered on the project database (see Appendix 4.1);

• A notification letter (in English and Afrikaans) was distributed to all identified I&APs (see Appendix 4.2

for letter and proof of distribution). The letter informed them of the release of the EIA Report and

where the report could be reviewed. To facilitate the commenting process, a copy of the Executive

Summary was enclosed with each letter; and

• Advertisements announcing the proposed project, the availability of the EIA Report and comment

period were placed in the Namibian (English) and Republikein (Afrikaans) newspapers on 7 August

2017 (see Appendix 4.3).

Two written submissions were received during the EIA Report review and comment period (see

Appendix 4.4). These comments have been collated, and responded to, in a Comments and Responses

Report (see Appendix 4.5). The key issues raised relate to the potential impact of seismic noise on marine

fauna and associated mitigation measures (including soft-start procedures, survey scheduling and survey

termination).




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3 PROJECT DESCRIPTION

This chapter provides general information on the proposed project, a brief background description of seismic

surveys and a detailed description of the seismic survey specifications.

3.1 GENERAL INFORMATION

3.1.1 OPERATOR

Spectrum has applied to undertake the seismic survey under a Multi-Client Agreement with NAMCOR and

will thus also be the operator for the proposed survey.

Address: Spectrum Geo

Dukes Court, Duke Street

Woking, Surrey, GU21 5BH

United Kingdom

New Ventures Manager: Mr John Hall

Telephone: + 44 (0) 1483 742 664

Facsimile: + 44 (0) 1483 762 620

Cell: + 44 (0) 7725 928 146

E-mail: [email protected]

3.1.2 EXISTING EXPLORATION / PRODUCTION RIGHT HOLDERS

The proposed survey area includes a number of licence blocks off the coast of northern Namibia (refer to

Figure 1.1). The licence block rights holders are presented in Table 3.1.

NAMCOR has advised that they will contact directly affected licence holders in order to inform them that

Spectrum is proposing to undertake a 3D seismic survey over their block(s).

Table 3.1: List of licence blocks and associated right holders in the proposed survey area.

No. Block Right Holder

1. 1709 * unlicensed


3. 1711A & B Shaanxi YP


5. 1810 Grisham Assets Corp

6. 1811A * unlicensed

7. 1811B Kayuco




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3.1.3 MONITORING AND EMP PERFORMANCE ASSESSMENT

Spectrum would undertake appropriate monitoring during the proposed seismic survey programme, and

would track performance against objectives and targets specified in the EMP (see Chapter 7 of this report).

At the conclusion of the proposed seismic survey programme a “Close-out” Report would be prepared, which

would include a monitoring and performance assessment for the survey. This report would outline the

implementation of the EMP and highlight any problems and issues that arose during the seismic survey.

A copy of this report would be sent to MME.

3.1.4 EMERGENCY PLANS

Spectrum and the appointed seismic contractor (see Section 3.3.2) would prepare a project specific

Emergency Response Plan (ERP) and Shipboard Oil Pollution Emergency Plan (SOPEP) for the proposed

seismic survey, which would define their organisational structure and protocols that would be implemented to

respond to any major incident (e.g. accidental oil / fuel spills, collisions, etc.) in a safe, rapid, effective and

efficient manner.

These plans would be submitted to MME for information purposes as part of their formal notification prior to

survey commencement.

3.2 TYPICAL SEISMIC SURVEYS

3.2.1 INTRODUCTION

Seismic surveys are carried out during oil and gas exploration activities in order to investigate subsea

geological formations. During seismic surveys, high-level, low frequency sounds are directed towards the

seabed from near-surface sound sources (source arrays) towed by a seismic vessel. Signals reflected from

geological interfaces below the seafloor are recorded by multiple receivers (or hydrophones) towed in a

single or multiple streamer configuration (see Figure 3.1). Analyses of the returned signals allow for

interpretation of subsea geological formations.

Seismic surveys are undertaken to collect geophysical data in either 2D or 3D mode. 2D seismic surveys

are typically acquired to obtain regional data from widely spaced survey grids (tens of kilometres).

3D seismic surveys are typically acquired over promising petroleum prospects to assist in fault interpretation,

distribution of sand bodies, estimates of oil and gas in place and the location of boreholes.

For this investigation Spectrum is proposing to undertake a 3D seismic survey.




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Figure 3.1: Principles of offshore seismic acquisition surveys (from fishsafe.eu).

3.2.2 SURVEY METHODOLOGY AND AIRGUN ARRAY

Seismic surveys are usually conducted using a purpose-built seismic vessel. Such vessels are

approximately 50 to 65 m in length with a Gross Registered Tonnage (GRT) between 1 000 and 6 500 t.

The seismic vessel would travel along specific pre-plotted survey lines covering a prescribed grid within the

survey area that have been carefully chosen to cross any known or suspected geological structure. During

surveying, the seismic vessel would travel on specific line headings at a speed of between four and five

knots (i.e. 2 to 3 metres per second). With equipment deployed the vessel would have limited

manoeuvrability (see Section 3.2.5).

The seismic survey would involve a towed airgun array, which provides the seismic source energy for the

profiling process, and a seismic wave detector system, usually known as a hydrophone streamer.

The anticipated airgun and hydrophone array would be dependent on whether a 2D or 3D seismic survey is

undertaken. The sound source or airgun array (one for 2D and two for 3D) would be situated some 80 m to

150 m behind the vessel at a depth of 5 m to 25 m below the surface. A 2D survey typically involves a single

streamer, whereas 3D surveys use multiple streamers (up to 12 streamers spaced 100 m apart). The array

can be up to 12 000 m long. The streamer/s would be towed at a depth of between 6 m and 30 m and would

not be visible, except for the tail-buoy at the far end of the cable. A typical 3D seismic survey configuration

and safe operational limits are illustrated in Figure 3.2.

At all times, the survey vessel would be accompanied by at least one support vessel. Support vessels would

act as guard vessels for the towed equipment, would clear surface debris/obstructions in the path of the main

acquisition vessel and inform local shipping and fishing traffic of the nature of the operation in the area

(see Section 3.2.5).




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Figure 3.2: Typical configuration and safe operational limits for 3D seismic survey operations.

3.2.3 SOUND PRESSURE EMISSION LEVELS

Airguns, which are the most common sound source used in modern seismic surveys, would be used for the

proposed survey. The airgun is an underwater pneumatic device from which high-pressure air is released

suddenly into the surrounding water. On release of pressure the resulting bubble pulsates rapidly producing

an acoustic signal that is proportional to the rate of change of the volume of the bubble. The frequency of

the signal depends on the energy of the compressed air prior to discharge. Airguns are used on an

individual basis (usually for shallow water surveys) or in arrays. Arrays of airguns are made up of towed

parallel strings, usually comprised of a total of 20 to 40 airguns.

Airguns have most of their energy in the 0-120 Hz frequency range, with the optimal frequency required for

deep penetration seismic work being 50-80 Hz. The maximum sound pressure levels at the source of airgun

array would be in the range 220-230 dB re 1µPa at 1 m (McCauley 1994; NRC 2003).

One of the required characteristics of a seismic shot is that it is of short duration (the main pulse is usually

between 5 and 30 milliseconds in duration). The main pulse is followed by a negative pressure reflection

from the sea surface of several lower magnitude bubble pulses (see Figure 3.3). Despite peak levels within

each shot being high, the total energy delivered into the water is low.

Paravane

3 km

4 km

4 km

3 km

8 km

12 km

6 km 6 km

Airgun array


Tail-buoys



Not to scale




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Figure 3.3: A typical pressure signature produced on firing of an airgun.

3.2.4 RECORDING EQUIPMENT

Signals reflected from geological discontinuities below the seafloor are recorded by hydrophones mounted

inside streamer cables. Hydrophones are typically made from piezoelectric material encased in a rubber

plastic hose. This hose containing the hydrophones is called a streamer. The reflected acoustic signals are

recorded and transmitted to the seismic vessel for electronic processing. Analyses of the returned signals

allow for interpretation of subsea geological formations.

3.2.5 EXCLUSION ZONE

The acquisition of high quality seismic data requires that the position of the survey vessel and the array be

accurately known. Seismic surveys consequently require accurate navigation of the sound source over pre-

determined survey transects. This, and the fact that the array and the hydrophone streamer need to be

towed in a set configuration behind the tow-ship, means that the survey operation has little manoeuvrability

while operating. For this reason the vessel is considered to be a fixed marine feature that is to be avoided by

other vessels.

Under the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972,

Part A, Rule 10), a seismic survey vessel that is engaged in surveying is defined as a “vessel restricted in its

ability to manoeuvre” which requires that power-driven and sailing vessels give way to a vessel restricted in

her ability to manoeuvre. Vessels engaged in fishing shall, so far as possible, keep out of the way of the

seismic survey operation. Furthermore, in terms of the Petroleum (Exploration and Production) Act, 1991

(No. 2 of 1991) a seismic vessel is considered to be an “offshore installation” and as such it is protected by a

500 m safety zone. It is an offence for an unauthorised vessel to enter the safety zone. In addition to a

statutory 500 m safety zone, a seismic contractor would request a safe operational limit (that is greater than

the 500 m safety zone) that it would like other vessels to stay beyond. Typical safe operational limits for

3D surveys are illustrated in Figure 3.2.




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At least a 500 m safety zone would need to be enforced around the survey vessel (including its array of

airguns and streamer) at all times. A support vessel with appropriate radar and communications would be

used during the seismic survey to warn vessels that are in danger of breaching the exclusion zone.

The 500 m safety zone and proposed safe operational limits would be communicated to key stakeholders

well in advance of the proposed seismic surveys. Notices to Mariners would also be communicated through

the proper channels.

3.3 DETAILED SEISMIC SURVEY SPECIFICATIONS

3.3.1 SEISMIC SURVEY PROGRAMME

The proposed 3D seismic survey area is 12 940 km2 in extent and is situated roughly between the Namibian

– Angolan border (17º 14’ S) and 18º 08’ S (see Figure 1.1). Water depths in the survey area range from

approximately 150 m in the east to depths greater than 4 000 m in the west. The survey area is located

27 km from shore at its closest point.

Although survey commencement would ultimately depend on when clearance is obtained from MME and

vessel availability, Spectrum proposes to commence with the 3D seismic survey in the fourth quarter of

2017. It is anticipated that the proposed 3D seismic would take in the order of nine (9) to ten (10) months to

complete.

3.3.2 SEISMIC CONTRACTOR

Spectrum proposes to contract BGP Inc. to undertake the proposed 3D seismic survey. BGP is a member of

the International Association of Geophysical Contractors (IAGC). BGP’s relevant contact details are

provided below:

Address: PO Box 11

Zhuozhou Hebei, 072751

P.R.China

Telephone: +86 10 81201850 / 81201469

Facsimile: +86 10 81201392

Email: [email protected]

3.3.3 SEISMIC SURVEY VESSEL

Although the survey vessel to be used would depend on vessel availably, currently BGP proposes to use the

vessel, BGP Prospector for the seismic survey. Table 3.2 provides some of the basic specifications of the

survey vessel. Further vessel specifications are included in Appendix 5.

A support vessel (to be confirmed) would be commissioned as the support / "chase" boat for the seismic

survey. This vessel would be equipped with appropriate radar and communications to patrol the area during

the seismic survey to ensure that other vessels adhere to the safe operational limits. The chase boat would

assist in alerting other vessels (e.g. fishing, transport, etc.) about the proposed survey and the lack of

manoeuvrability of the survey vessel. The chase boat would also be required, if necessary, to perform

logistics support to the survey vessel.




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Table 3.2: Vessel specifications.

Specification BGP Prospector

Flag Bahamas

Call sign C6YF5

Length 100 m

Breadth 24 m

Draft (mean / max) 6.4 m / 7.3 m

Gross tonnage 11 080 t

Speed (max) 16 knots

3.3.4 ANTICIPATED AIRGUN AND HYDROPHONE ARRAY SPECIFICATIONS

Anticipated specifications for the source and receiver arrays are summarised in Table 3.3.

Table 3.3: Airgun and hydrophone array specifications.

No. of airgun arrays 2

No. of active airguns 10 to 12 per string

Airgun array volume 4 200 cu.in

Airgun operating pressure 2 000 – 3 000 psi

Depth of airgun 5 to 8 m*

Distance of airgun behind vessel 50 to 200 m

Streamers (number and length) 12 x 8 000 m

Streamer depth 9 to 17 m*

*Note: Subject to final survey acquisition design

3.3.5 SUPPORT SERVICES

Vessel supplies, including food, water, and fuel will likely be loaded at the Port of Walvis Bay. Alternatively,

a support vessel would be used to perform logistics support to the seismic vessel, including crew changes.

Crew changes would occur in the Port of Walvis Bay or via helicopter and / or supply vessel (most likely

alternative) from Walvis Bay.

Bunkering of the survey vessel is expected to be undertaken at the Port of Walvis Bay or at sea during the

survey. Standard operating procedures for refuelling will be adhered to at all times.




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4 DESCRIPTION OF THE AFFECTED ENVIRONMENT

This chapter provides a description of the baseline biophysical and socio-economic environment which could

potentially be affected by the proposed 3D seismic survey.

4.1 GEOPHYSICAL CHARACTERISTICS

4.1.1 BATHYMETRY

The bathymetry of the continental margin off Namibia and south-western South Africa is illustrated in

Figure 4.1

The continental shelf off Namibia is variable in width. Off the Orange River the shelf is wide (230 km) and

characterised by well-defined shelf breaks, a shallow outer shelf and the aerofoil-shaped submarine Recent

River Delta on the inner shelf. It narrows further north reaching its narrowest point (90 km) off Chameis Bay,

before widening again to 130 km off Lüderitz. Off Terrace Bay the shelf gives rise to the Walvis Ridge, an

underwater plateau extending south-westwards far into the south Atlantic, before narrowing again towards

Cape Frio. Off Walvis Bay there is a double shelf break, with the inner and outer breaks beginning at depths

of around 140 m and 400 m, respectively (Shannon & O’Toole 1998).

The salient topographic features of the shelf include the relatively steep descent to about 100 m, the gentle

decline to about 180 m and the undulating depths to about 200 m. The most prominent topographic feature

in the study area is the Walvis Ridge, which extends from the African coast at around 18°S more than

3 000 km south-westwards to Tristan da Cunha, the Gough Islands and the Mid-Atlantic Ridge. This plateau

effectively splits the abyssal plain of the south-east Atlantic into the Angola Basin to the north and the Cape

Basin to the south. The variable topography of the shelf is of significance for nearshore circulation and for

fisheries (Shannon & O’Toole 1998).

Water depths in the survey area range from approximately 150 m in the east to depths greater than 4 000 m

in the west. The survey area is located approximately 27 km from shore at its closest point.

4.1.2 COASTAL AND INNER-SHELF GEOLOGY AND SEABED GEOMORPHOLOGY BATHYMETRY

The distribution of seabed surface sediment types off the northern Namibian coast is illustrated in Figure 4.2.

The inner shelf is underlain by Precambrian bedrock (also referred to as Pre-Mesozoic basement), whilst the

middle and outer shelf areas are composed of Cretaceous and Tertiary sediments (Rogers & Bremner 1991).

As a result of erosion on the continental shelf, the unconsolidated sediment cover is generally thin, often less

than 1 m. Sediments are finer seawards, changing from sand on the inner and outer shelves to muddy sand

and sandy mud in deeper water. However, this general pattern has been modified considerably by biological

deposition (large areas of shelf sediments contain high levels of calcium carbonate) and localised river input.

Off central Namibia, the muddy sand in the nearshore area off Henties Bay gives way to a tongue of organic-

rich sandy mud, which extends from south of Sandwich Harbour to ~ 20°40’S (see Figure 4.2). These

biogenic muds are the main determinants of the formation of low-oxygen waters and sulphur eruptions off

central Namibia (see Sections 4.2.7 and 4.2.8). Further offshore these give way to muddy sands, sands and

gravels before changing again into mud-dominated seabed beyond the 500 m contour. The continental

slope, seaward of the shelf break, has a smooth seafloor, underlain by calcareous ooze.




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Figure 4.1: Bathymetry of the continental margin off Namibia and south-western South Africa.

From Rogers and Bremner (1991). Approximate location of the survey area is also

shown.




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Figure 4.2: The proposed survey area and lines in relation to the sediment distribution on the

continental shelf off northern Namibian (Adapted from Rogers 1977).

4.2 BIOPHYSICAL CHARACTERISTICS

4.2.1 CLIMATE

The climate of the Namibian coastline is classified as hyper-arid with typically low, unpredictable winter rains

and strong predominantly southerly or south-westerly winds. Further out to sea, a south-easterly component

is more prominent. Winds reach a peak in the late afternoon and subside between midnight and sunrise.

The Namibian coastline is characterised by the frequent occurrence of fog, which occurs on average

between 50 and 75 days per year, being most frequent during the months of February through May

(see Figure 4.3). The fog lies close to the coast extending about 20 nautical miles (nm) (~35 km) seawards

(Olivier, 1992, 1995). This fog is usually quite dense, appearing as a thick bank hugging the shore and

reducing visibility to <300 m.

Average precipitation per annum along the coastal region between Walvis Bay and the Kunene River is

<15 mm. Due to the combination of wind and cool ocean water, temperatures are mild throughout the year.

Coastal temperatures average around 16°C, gradually increasing inland (Barnard 1998). In winter,

maximum diurnal shifts in temperature can occur caused by the hot easterly ‘berg’ winds which blow off the

desert. During such occasions temperatures up to 30°C are not uncommon.




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Figure 4.3: Fog day frequency for 1984 using Meteosat Images (Adapted from Olivier 1992, 1995).




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The atmospheric features and processes active on the West Coast of southern Africa have been described

by Nelson & Hutchings (1983), Kamstra (1985), Shannon (1985), Shannon & Nelson (1996) and Shannon &

O’Toole (1998). The description below is summarised from these authors.

The prevailing winds in the Benguela region are controlled by the South Atlantic subtropical anticyclone, the

eastward moving mid-latitude cyclones south of southern Africa, and the seasonal atmospheric pressure field

over the subcontinent. The south Atlantic anticyclone is a perennial feature that forms part of a

discontinuous belt of high-pressure systems that encircle the subtropical southern hemisphere. This

undergoes seasonal variations, being strongest in the austral summer, when it also attains its southernmost

extension, lying south west and south of the subcontinent. In winter, the south Atlantic anticyclone weakens

and migrates north-westwards. These seasonal changes result in substantial differences between the typical

summer and winter wind patterns in the region, as the southern hemisphere anti-cyclonic high-pressure

system, and the associated series of cold fronts, move northwards in winter, and southwards in summer.

Seasonal wind roses for Pelican Point near Walvis Bay are illustrated in Figure 4.4. The strongest winds

occur in summer, when winds blow 99% of the time. Virtually all winds in summer are strongly dominated by

southerlies, which occur over 40% of the time, averaging 20 - 30 kts and reaching speeds in excess of

60 kts. In northern Namibia longshore south-easterly winds dominate in summer, whereas off Walvis Bay

south-south-westerlies dominate and wind speeds are generally lower on average and display less

seasonality than in the south of the country (Shannon & O’Toole 1998). These southerly winds bring cool,

moist air into the coastal region and drive the massive offshore movements of surface water, and the

resultant strong upwelling of nutrient-rich bottom waters, which characterise this region in summer.

The winds also play an important role in the loss of sediment from beaches. These strong equatorwards

winds are interrupted by the passing of coastal lows with which are associated periods of calm or north or

northwest wind conditions. These northerlies occur throughout the year, but are more frequent in spring and

summer.

Winter remains dominated by southerly winds, but the closer proximity of the winter cold-front systems

results in a significant north-westerly component. This ‘reversal’ from the summer condition results in

cessation of upwelling, movement of warmer mid-Atlantic water shorewards and breakdown of the strong

thermoclines which typically develop in summer.

During autumn and winter, the south Atlantic anticyclone weakens and migrates north-westwards causing

catabatic or easterly ‘berg’ winds. These powerful offshore winds can exceed 50 km/h, producing

sandstorms that considerably reduce visibility at sea and on land. Although they occur intermittently for

about a week at a time, they have a strong effect on the coastal temperatures, which often exceed 30°C

during ‘berg’ wind periods (Shannon & O’Toole 1998). The winds also play a significant role in sediment

input into the coastal marine environment with transport of the sediments up to 150 km offshore.

4.2.2 LARGE-SCALE CIRCULATION AND COASTAL CURRENTS

The Namibian coastline is strongly influenced by the Benguela Current system; a major eastern boundary

current off the West Coast of southern Africa. It is characterised by coastal upwelling of cold nutrient-rich

water, and is an important centre of plankton production, which supports a global reservoir of biodiversity and

biomass of sea life (Shannon, 1985). Located off the south-west coast of Africa, the Benguela is divided into

northern and southern sub-systems that are divided by the permanent upwelling cell at Lüderitz 26°S

(van der Lingen et al., 2006). The northern Benguela system extends from the Angola Benguela Frontal

Zone between 14-16°S to the Lüderitz upwelling cell, whereas the southern Benguela system extends from

Lüderitz to the Agulhas bank off South Africa’s South Coast (see Figure 4.5).




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Figure 4.4: Seasonal wind roses for Pelican Point (Source PRDW 2008).




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Current velocities in continental shelf areas generally range between 10 to 30 cm/s (Boyd & Oberholster

1994). The flows are predominantly wind-forced, barotropic and fluctuate between poleward and

equatorward flow (Shillington et al. 1990; Nelson & Hutchings 1983) (see Figure 4.5). Fluctuation periods of

these flows are three to 10 days, although the long-term mean current residual is in an approximate

northwesterly (alongshore) direction. Near bottom shelf flow is mainly poleward (Nelson 1989) with low

velocities of typically 5 cm/s.

Figure 4.5: Map of the south-east Atlantic showing surface and near-surface currents, frontal

zones, upwelling cells, major areas of freshwater input and bathymetry (re-drawn from

Shannon & Nelson 1996). Approximate location of the survey area is also shown.




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The Angola Dome lies to the north of the survey area and is characterised by cyclonic circulation, with

periodic intrusion of tropical waters into the northern Benguela from the north and northwest. Off the coast of

Angola, the most prominent circulation feature is the southward flowing Angola current, which turns

westwards between 16°S and 17°S just north of the Angola-Benguela Front. The Angola-Benguela Front is

a permanent feature at the surface and to a depth of at least 200 m between latitudes 14°S and 17°S.

The front is maintained by a combination of factors including coastal orientation, wind stress, bathymetry and

opposing flows of the Angola and Benguela Currents. To what extent the Angola Current contributes to the

Benguela system at the surface and subsurface off northern Namibia is uncertain. At greater depths

(400 m), however, the poleward flow of the Angola Current is more continuous. The episodic southward

movement of this front during late summer introduces warm tropical water southwards and eastwards along

the Namibian coast. Known as Beguela Niños, these events occur on average every 10 years (Shannon &

O’Toole 1998).

The major feature of the Benguela Current is upwelling and the consequent high nutrient supply to surface

waters leads to high biological production. The prevailing longshore, equatorward winds move nearshore

surface water northwards and offshore. To balance the displaced water, cold, deeper water wells up

inshore. Although the rate and intensity of upwelling fluctuates with seasonal variations in wind patterns, the

most intense upwelling tends to occur where the shelf is narrowest and the wind strongest. Consequently, it

is a semi-permanent feature at Lüderitz and areas to the north due to perennial southerly winds (Shannon

1985). The Lüderitz upwelling cell is the most intense upwelling cell in the system (see Figure 4.6), with the

seaward extent reaching nearly 300 km, and the upwelling water is derived from 300 to 400 m depth

(Longhurst 2006). A detailed analysis of water mass characteristics revealed a discontinuity in the central

and intermediate water layers along the shelf north and south of Lüderitz (Duncombe Rae 2005). The

Lüderitz / Orange River region forms thus a major environmental barrier between the northern and southern

Benguela sub-systems (Ekau & Verheye 2005). Off northern and central Namibia, several secondary

upwelling cells occur. Upwelling in these cells is perennial, with a late winter maximum (Shannon 1985).

4.2.3 TIDES

In common with the rest of the southern African coast, tides are semi-diurnal, with a total range of some

1.5 m at spring tide and only 0.6 m during neap tide periods.

4.2.4 WAVES

The Namibian coast is classified as exposed, experiencing strong wave action rating from 13-17 on the 20-

point exposure scale (McLachlan 1980). The coastline is influenced by major swells generated in the roaring

forties, as well as significant sea waves generated locally by the persistent southerly winds.

Typical seasonal swell-height rose-plots are illustrated in Figure 4.7. The wave regime along the southern

African West Coast shows only moderate seasonal variation in direction, with virtually all swells throughout

the year coming from the south-west to south direction. In winter there is a slight increase in swell from the

south-west direction. The median significant wave height is 2.4 m with a dominant peak energy period of

approximately 12 seconds. Longer period swells (11 to 15 seconds), generated by mid-latitude cyclones

occur about 25-30 times a year. These originate from the south to south-west sectors, with the largest

waves recorded along the southern African West Coast attaining 4-7 m. With wind speeds capable of

reaching 100 km/h during heavy winter south-westerly storms, winter swell heights can exceed 10 m.

Generally, wave heights decrease with water depth and distance longshore.




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In comparison, spring and summer swells tend to be smaller on average, typically around 2 m, not reaching

the maximum swell heights of winter. There is also a more pronounced southerly swell component in

summer. These southerly swells tend to be wind-induced, with shorter wave periods (approximately

8 seconds), and are generally steeper than swell waves (CSIR 1996). These wind-induced southerly waves

are relatively local and, although less powerful, tend to work together with the strong southerly winds of

summer to cause the northward-flowing nearshore surface currents, and result in substantial nearshore

sediment mobilisation, and northwards transport, by the combined action of currents, wind and waves.

Figure 4.6: Upwelling centres on the West Coast of Namibia (Adapted from Shannon 1985).

Approximate location of the survey area and lines is also shown.




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Figure 4.7: Seasonal offshore wave conditions for a data point located at 23° S, 13.75°E (CSIR

2009).

4.2.5 TURBIDITY

Turbidity is a measure of the degree to which the water loses its transparency due to the presence of

suspended particulate matter. Total Suspended Particulate Matter (TSPM) can be divided into Particulate

Organic Matter (POM) and Particulate Inorganic Matter (PIM), the ratios between them varying considerably.

The POM usually consists of detritus, bacteria, phytoplankton and zooplankton, and serves as a source of

food for filter-feeders. Seasonal microphyte production associated with upwelling events plays an important

role in determining the concentrations of POM in coastal waters. PIM, on the other hand, is primarily of




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geological origin consisting of fine sands, silts and clays. Off the southern African West Coast, the PIM

loading in nearshore waters is strongly related to natural riverine inputs. ‘Berg’ wind events can potentially

contribute the same order of magnitude of sediment input as the annual estimated input of sediment by the

Orange River (Shannon & Anderson 1982; Zoutendyk 1992, 1995; Shannon & O’Toole 1998; Lane & Carter

1999).

Concentrations of suspended particulate matter in shallow coastal waters can vary both spatially and

temporally, typically ranging from a few mg/l to several tens of mg/l (Bricelj & Malouf 1984; Berg & Newell

1986; Fegley et al. 1992). Field measurements of TSPM and PIM concentrations in the Benguela current

system have indicated that background concentrations of coastal and continental shelf suspended sediments

are generally <12 mg/l, showing significant long-shore variation (Zoutendyk 1995). Considerably higher

concentrations of PIM have, however, been reported from southern African West Coast waters under

stronger wave conditions associated with high tides and storms, or under flood conditions.

The major source of turbidity in the swell-influenced nearshore areas off the West Coast is the redistribution

of fine inner shelf sediments by long-period Southern Ocean swells. The current velocities typical of the

Benguela (10-30 cm/s) are capable of resuspending and transporting considerable quantities of sediment

equatorwards. Under relatively calm wind conditions, however, much of the suspended fraction (silt and

clay) that remains in suspension for longer periods becomes entrained in the slow poleward undercurrent

(Shillington et al. 1990; Rogers & Bremner 1991).

Superimposed on the suspended fine fraction is the northward littoral drift of coarser bedload sediments,

parallel to the coastline. This northward, nearshore transport is generated by the predominantly south-

westerly swell and wind-induced waves. Longshore sediment transport varies considerably in the shore-

perpendicular dimension, being substantially higher in the surf-zone than at depth, due to high turbulence

and convective flows associated with breaking waves, which suspend and mobilise sediment (Smith &

Mocke 2002).

On the inner and middle continental shelf, the ambient currents are insufficient to transport coarse

sediments, and resuspension and shoreward movement of these by wave-induced currents occur primarily

under storm conditions (Drake et al. 1985; Ward 1985).

4.2.6 ORGANIC INPUTS

The Benguela upwelling region is an area of particularly high natural productivity, with extremely high

seasonal production of phytoplankton and zooplankton. These plankton blooms in turn serve as the basis

for a rich food chain up through pelagic baitfish (anchovy, pilchard, round-herring and others) to predatory

fish (snoek), mammals (primarily seals and dolphins) and seabirds (jackass penguins, cormorants, pelicans,

terns and others). All of these species are subject to natural mortality and a proportion of the annual

production of all these trophic levels, particularly the plankton communities, die naturally and sink to the

seabed.

Balanced multispecies ecosystem models have estimated that during the 1990s the Benguela region

supported biomasses of 76.9 tons/km2 of phytoplankton and 31.5 tons/km

2 of zooplankton alone (Shannon et

al. 2003). Thirty-six percent of the phytoplankton and 5% of the zooplankton are estimated to be lost to the

seabed annually. This natural annual input of millions of tons of organic material onto the seabed off the

southern African West Coast has a substantial effect on the ecosystems of the Benguela region. It provides

most of the food requirements of the particulate and filter-feeding benthic communities that inhabit the sandy-

muds of this area, and results in the high organic content of the muds in the region. As most of the organic




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detritus is not directly consumed, it enters the seabed decomposition cycle, resulting in subsequent depletion

of oxygen in deeper waters overlying these muds (see Section 4.2.7) and the generation of hydrogen

sulphide and sulphur eruptions along the coast (see Section 4.2.8).

An associated phenomenon ubiquitous to the Benguela system is red tides (dinoflagellate and/or ciliate

blooms) (Shannon & Pillar 1985; Pitcher 1998) or Harmful Algal Blooms (HABs). These red tides can reach

very large proportions, with sometimes spectacular effects. Toxic dinoflagellate species can cause extensive

mortalities of fish and shellfish through direct poisoning, while degradation of organic-rich material derived

from both toxic and non-toxic blooms results in oxygen depletion of subsurface water.

4.2.7 LOW OXYGEN EVENTS

The continental shelf waters of the Benguela system are characterised by low oxygen concentrations with

<40% saturation occurring frequently (Bailey et al. 1985). The low oxygen concentrations are attributed to

nutrient remineralisation in the bottom waters of the system (Chapman & Shannon 1985). The absolute

rate of this is dependent upon the net organic material build-up in the sediments, with the carbon rich

mud deposits playing an important role. As the mud on the shelf is distributed in discrete patches

(see Figure 4.2), there are corresponding preferential areas for the formation of oxygen-poor water

(see Figure 4.6). The two main areas of low-oxygen water formation in the central Benguela region are in

the Orange River Bight and off Walvis Bay (Chapman & Shannon 1985; Bailey 1991; Shannon & O’Toole

1998; Bailey 1999; Fossing et al. 2000). The spatial distribution of oxygen-poor water in each of the areas is

subject to short- and medium-term variability in the volume of hypoxic water that develops. De Decker

(1970) showed that off Lambert’s Bay in South Africa, the occurrence of low oxygen water is seasonal, with

highest development in summer/autumn. Bailey & Chapman (1991), on the other hand, demonstrated that in

the St Helena Bay area in South Africa, daily variability exists as a result of downward flux of oxygen through

thermoclines and short-term variations in upwelling intensity. Subsequent upwelling processes can move

this low-oxygen water up onto the inner shelf, and into nearshore waters, often with devastating effects on

marine communities.

Periodic low oxygen events in the nearshore region can have catastrophic effects on the marine communities

leading to large-scale stranding of rock lobsters, and mass mortalities of marine biota and fish (Newman &

Pollock 1974; Matthews & Pitcher 1996; Pitcher 1998; Cockcroft et al. 2000). The development of anoxic

conditions as a result of the decomposition of huge amounts of organic matter generated by algal blooms is

the main cause for these mortalities and walkouts. The blooms develop over a period of unusually calm wind

conditions when sea surface temperatures where high. Algal blooms usually occur during summer-autumn

(February to April) but can also develop in winter during the ‘berg’ wind periods, when similar warm windless

conditions occur for extended periods.

4.2.8 SULPHUR ERUPTIONS

Closely associated with seafloor hypoxia, particularly off central Namibia, is the generation of toxic hydrogen

sulphide and methane within the organically-rich, anoxic muds following decay of expansive algal blooms.

Under conditions of severe oxygen depletion, hydrogen sulphide (H2S) gas is formed by anaerobic bacteria

in anoxic seabed muds (Brüchert et al. 2003). This is periodically released from the muds as ‘sulphur

eruptions’, causing upwelling of anoxic water and formation of surface slicks of sulphur discoloured

water (Emeis et al. 2004), and even the temporary formation of floating mud islands. Such eruptions are

accompanied by a characteristic pungent smell along the coast and the sea takes on a lime green colour.

These eruptions strip dissolved oxygen from the surrounding water column, resulting in mass mortalities of




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marine life. Such complex chemical and biological processes are often associated with the occurrence of

harmful algal blooms, causing large-scale mortalities to fish and crustaceans (see Section 4.2.7).

Sulphur eruptions have been known to occur off the Namibian coast for centuries, and the biota in the area

are likely to be naturally adapted to such pulsed events, and to subsequent hypoxia. However, satellite

remote sensing has recently shown that eruptions occur more frequently, are more extensive and of longer

duration than previously suspected, and that resultant hypoxic conditions last longer than thought (Weeks et

al. 2002, 2004).

An intermediate layer was recently discovered in the water column, which contained neither hydrogen

sulphide nor oxygen. It was established that sulphide diffusing upwards from the anoxic bottom water is

consumed by autotrophic denitrifying bacteria that inhabit the intermediate water layer. By using nitrate, the

detoxifying micro-organisms transform sulphide into finely dispersed particles of sulphur that are non-toxic,

thereby creating a buffer zone between the toxic deep water and the oxygenated surface waters. These

results, however, also suggest that benthic and demersal animals in coastal waters may be affected by

sulphur eruptions more often than previously thought, and that many of these sulphidic events may go

unnoticed on satellite imagery as the bacteria consume the hydrogen sulphide before it reaches the surface.

4.3 BIOLOGICAL OCEANOGRAPHY

Biogeographically, the study area falls into the warm-temperate Namib Province, which extends northwards

from Lüderitz into southern Angola (Emanuel et al. 1992). The portion of the proposed survey area that

extends beyond the shelf break onto the continental slope and into abyssal depths falls into the Atlantic

Offshore Bioregion (Lombard et al. 2004). The coastal, wind-induced upwelling characterising the Namibian

coastline, is the principle physical process which shapes the marine ecology of the central Benguela region.

The Benguela system is characterised by the presence of cold surface water, high biological productivity,

and highly variable physical, chemical and biological conditions. During periods of less intence winds off the

northern Nambian coast (Benguela Niños), upwelling weakens and the warmer, more saline waters of the

Angola Current intrude southwards along the coast introducing organisms normally associated with the

subtropical conditions typical off Angola (Barnard 1998). As these events are typically temporary, the

species of tropical west African origin associated with them are not discussed below.

Communities within marine habitats are largely ubiquitous throughout the southern African West Coast

region, being particular only to substrate type or depth zone. These biological communities consist of many

hundreds of species, often displaying considerable temporal and spatial variability (even at small scales).

The majority of the proposed survey area is located beyond the 150 m depth contour, the closest points to

shore for the 3D seismic survey being approximately 27 km off the coast west off Cape Frio. The near- and

offshore marine ecosystems comprise a limited range of habitats, namely unconsolidated seabed sediments

and the water column. The biological communities ‘typical’ of each of these habitats are described briefly

below, focussing both on dominant, commercially important and conspicuous species, as well as potentially

threatened or sensitive species, which may be affected by the proposed seismic survey programme.




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4.3.1 OFFSHORE BENTHIC COMMUNITIES

4.3.1.1 Benthic invertebrate macro fauna

The benthic biota of soft-bottom substrates constitutes invertebrates that live on (epifauna) or burrow within

(infauna) the sediments and are generally divided into macrofauna (>1 mm) and meiofauna (<1 mm).

Numerous studies have been conducted on southern African West Coast continental shelf benthos to

approximately 180 m depth, mostly focused on mining or pollution impacts (Christie & Moldan 1977; Moldan

1978; Jackson & McGibbon 1991; Environmental Evaluation Unit 1996; Parkins & Field 1997; 1998; Pulfrich

& Penney 1999b; Goosen et al. 2000; Savage et al. 2001; Steffani & Pulfrich 2004a, 2004b; 2007; Steffani

2007a; 2007b; Steffani 2009, 2010, 2012). The description below is drawn from the various baseline and

monitoring surveys conducted by diamond mining companies (Bickerton & Carter, 1995; Steffani & Pulfrich,

2007; Steffani, 2007a; 2007b).

Polychaetes, crustaceans and molluscs make up the largest proportion of individuals, biomass and species

on the West Coast. The distribution of species within these communities are inherently patchy reflecting the

high natural spatial and temporal variability associated with macro-infauna of unconsolidated sediments

(e.g. Kenny et al. 1998; Kendall & Widdicombe 1999; van Dalfsen et al. 2000; Zajac et al. 2000; Parry et al.

2003), with evidence of mass mortalities and substantial recruitments recorded on the South African West

Coast (Steffani & Pulfrich 2004a). Generally species richness increases from the inner-shelf across the mid-

shelf and is influenced by sediment type. The highest total abundance and species diversity was measured

in sandy sediments of the mid-shelf. Biomass is highest in the inshore (± 50 g/m2 wet weight) and decreases

across the mid-shelf averaging around 30 g/m2 wet weight. The mid-shelf mud belt, however, is a

particularly rich benthic habitat where biomass can attain 60 g/m2 dry weight (Christie 1974; Steffani 2007b).

The comparatively high benthic biomass in this mud belt region represents an important food source to

carnivores such as the mantis shrimp, cephalopods and demersal fish species (Lane & Carter 1999). In

deeper water beyond this rich zone biomass declines to 4.9 g/m2 at 200 m depth and then is consistently low

(<3 g/m2) on the outer shelf (Christie 1974).

The benthic fauna of the outer-shelf and continental slope (beyond approximately 450 m depth) are very

poorly known largely. To date very few areas of the continental slope off the southern African West Coast

have been biologically surveyed.

Whilst many empirical studies related community structure to sediment composition (e.g. Christie 1974;

Warwick et al. 1991; Yates et al. 1993; Desprez 2000; van Dalfsen et al. 2000), other studies have illustrated

the high natural variability of soft-bottom communities, both in space and time, on scales of hundreds of

metres to metres (e.g. Kenny et al. 1998; Kendall & Widdicombe 1999; van Dalfsen et al. 2000; Zajac et al.

2000; Parry et al. 2003), with evidence of mass mortalities and substantial recruitments (Steffani & Pulfrich

2004a). It is likely that the distribution of marine communities in the mixed deposits of the coastal zone is

controlled by complex interactions between physical and biological factors at the sediment-water interface,

rather than by the granulometric properties of the sediments alone (Snelgrove & Butman 1994; Seiderer &

Newell 1999).

It is evident that an array of environmental factors and their complex interplay is ultimately responsible for the

structure of benthic communities. However, the relative importance of each of these factors is difficult to

determine as these factors interact and combine to define a distinct habitat in which the animals occur.

However, it is clear that water depth and sediment composition are two of the major components of the

physical environment determining the macrofauna community structure off the West Coast of southern Africa

(Steffani & Pulfrich 2004a, 2004b, 2007; Steffani 2007a, 2007b, 2009a, 2009b, 2009c, 2010). However, in

the deep-water shelf areas off central Namibia, it is likely that occurrence of Oxygen Minimum Zones (OMZs)




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and the periodic intrusion of low oxygen water masses will play a major role in determining variability in

community structure (Monteiro & van der Plas 2006).

Specialised benthic assemblages (protozoans and metazoans) can thrive in OMZs (Levin, 2003) and many

organisms have adapted to low oxygen conditions by developing highly efficient ways to extract oxygen from

depleted water. Within OMZs, benthic foraminiferans, meiofauna and macrofauna typically exhibit high

dominance and relatively low species richness. In the OMZ core, where oxygen concentration is lowest,

macrofauna and megafauna (>10 cm) often have depressed densities and low diversity, despite being able

to form dense aggregations at OMZ edges (Levin, 2003; Levin et al., 2009). Taxa most tolerant of severe

oxygen depletion (~0.2 ml/ℓ) include calcareous foraminiferans, nematodes and polychaetes, with

agglutinated protozoans, harpacticoid copepods and calcified invertebrates typically being less tolerant.

Small-bodied animals, with greater surface area for oxygen adsorption, are thought to be more prevalent

than large-bodied taxa under conditions of permanent hypoxia as they are better able to cover their

metabolic demands and often able to metabolise anaerobically (Levin, 2003). Meiofauna may thus increase

in dominance in relation to macro- and megafauna. However, this was not the case within the lower OMZs

of the Oman (Levin et al., 2009) and Pakistan margins (Levin et al. 2009), where the abundant food supply in

the lower or edge OMZs is thought to be responsible for promoting larger macrofaunal body size.

There is a poor understanding of the responses of local continental shelf macrofauna to low oxygen

conditions, as very little is known about the benthic fauna specific to the Namibian OMZ. It is safe to assume

that in areas of frequent oxygen deficiency the communities will be characterised by species able to survive

chronic low oxygen conditions or colonising and fast-growing species able to rapidly recruit into areas that

have suffered complete oxygen depletion. Local hydrodynamic conditions and patchy settlement of larvae

will also contribute to small-scale variability of benthic community structure.

Recent data collected from between 150 m and 300 m depth offshore of the area between Meob Bay and

Conception Bay showed that overall species richness of benthic macrofauna assemblages was relatively low

and strongly dominated by polychaetes, particularly the spionid polychaete Paraprionospio pinnata. This

species is dominant in oxygen-constrained environments worldwide. Crustaceans were poorly represented,

both in terms of abundance and biomass (Steffani, 2011). The phyla distribution is generally in common with

other OMZs around the world.

It is evident that an array of environmental factors and their complex interplay is ultimately responsible for the

structure of benthic communities. Yet the relative importance of each of these factors is difficult to determine

as these factors interact and combine to define a distinct habitat in which the animals occur.

Also associated with soft-bottom substrates are demersal communities that comprise bottom-dwelling

invertebrate and vertebrate species, most of which are dependent on the invertebrate benthic macrofauna as

a food source. An invertebrate demersal species of commercial importance in Namibia is the deep-sea red

crab Chaceon maritae, which occurs at depths of 300 - 1 000 m along the entire West Coast of Africa from

West Sahara to central Namibia. In Namibia, densities are highest between the Kunene and latitude 18°S.

Larger animals tend to occur more frequently between latitudes 20° - 23°S, where densities are lower. The

species is slow-growing taking up to 25 30 years to reach maximum size. Females occur at depths of 350-

500 m, whereas males become more dominant in deeper water (Le Roux 1998). Spawning occurs

throughout the year.




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4.3.1.2 Deep-water coral communities, seamount communities and Vulnerable Marine Ecosystems

There has been increasing interest in deep-water corals (depths >150 m, with some species being recorded

up to 3 000 m) in recent years because of their likely sensitivity to disturbance and their long generation

times. Some species form reefs while others are smaller and remain solitary. Corals add structural

complexity to otherwise uniform seabed habitats thereby creating areas of high biological diversity (Breeze et

al. 1997; MacIssac et al. 2001).

Deep-water corals establish themselves below the thermocline where there is a continuous and regular

supply of concentrated particulate organic matter, caused by the flow of a relatively strong current over

special topographical formations which cause eddies to form. Nutrient seepage from the substratum might

also promote a location for settlement (Hovland et al. 2002). In the productive Benguela region, substantial

areas on and off the edge of the shelf could thus potentially be capable of supporting rich, cold water,

benthic, filter-feeding communities. Such communities would also be expected with topographic features

such as the Walvis Ridge (and its associated seamounts) to the south of the project area.

Features such as banks, knolls and seamounts (referred to collectively here as “seamounts”), which protrude

into the water column, are subject to, and interact with, the water currents surrounding them. The effects of

such seabed features on the surrounding water masses can include the upwelling of relatively cool, nutrient-

rich water into nutrient-poor surface water thereby resulting in higher productivity (Clark et al. 1999), which

can in turn strongly influence the distribution of organisms on and around seamounts. Evidence of

enrichment of bottom-associated communities and high abundances of demersal fishes has been regularly

reported over such seabed features.

The enhanced fluxes of detritus and plankton that develop in response to the complex current regimes lead

to the development of detritivore-based food-webs, which in turn lead to the presence of seamount

scavengers and predators. Deep- and cold-water corals (including stony corals, black corals and soft corals)

are a prominent component of the suspension-feeding fauna of many seamounts, accompanied by

barnacles, bryozoans, polychaetes, molluscs, sponges, sea squirts, basket stars, brittle stars and crinoids

(Rogers 2004). There is also associated mobile benthic fauna that includes echinoderms (sea urchins and

sea cucumbers) and crustaceans (crabs and lobsters) (Rogers 1994). Seamounts also provide an important

habitat for commercial deepwater fish stocks, such as orange roughy, oreos, alfonsino and Patogonian

toothfish, which aggregate around these features for either spawning or feeding (Koslow 1996).

The coral frameworks offer refugia for a great variety of invertebrates and fish within, or in association with,

the living and dead coral framework thereby creating spatially fragmented areas of high biological diversity

(biological hotspots). Such complex benthic ecosystems in turn enhance foraging opportunities for many

other predators, serving as mid-ocean focal points for a variety of pelagic species with large ranges (turtles,

tunas and billfish, pelagic sharks, cetaceans and pelagic seabirds) that may migrate large distances in

search of food or may only congregate on seamounts at certain times (Hui 1985; Haney et al. 1995).

Seamounts thus serve as feeding grounds, spawning and nursery grounds and possibly navigational

markers for a large number of species (SPRFMA 2007). Consequently, seamounts are usually highly unique

and are usually, but not always, identified as Vulnerable Marine Ecosystems (VMEs).

It is not always the case that seamount habitats are VMEs, as some seamounts may not host communities of

fragile animals or be associated with high levels of endemism. There is reference to decapods crustaceans

from Tripp Seamount (Kensley 1980, 1981) and exploratory deep-water trawl fishing (Hampton 2003), but

otherwise knowledge of benthic communities characterising southern African seamounts is lacking.

Evidence from video footage taken on hard-substrate habitats in 100 - 120 m depth off southern Namibia

suggest that vulnerable communities including gorgonians, octocorals and reef-building sponges occur on




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the continental shelf, and similar communities may thus be expected on seamounts associated with the

Walvis Ridge.

4.3.2 PLANKTON


characteristic of the area. Plankton range from single-celled bacteria to jellyfish of 2 m diameter and include

bacterio-plankton, phytoplankton, zooplankton, and ichthyoplankton.

Off the Namibian coastline, phytoplankton are the principle primary producers with mean annual productivity

being comparatively high at 2 g C/m2/day (Barnard 1998). The phytoplankton is dominated by diatoms,

which are adapted to the turbulent sea conditions. Diatom blooms occur after upwelling events, whereas

dinoflagellates are more common in blooms that occur during quiescent periods, since they can grow rapidly

at low nutrient concentrations. In the surf zone, diatoms and dinoflagellates are nearly equally important

members of the phytoplankton, and some silicoflagellates are also present.

Namibian zooplankton reaches maximum abundance in a belt parallel to the coastline and offshore of the

maximum phytoplankton abundance. Samples collected over a full seasonal cycle (February to December)

along a 10 to 90 nm transect offshore Walvis Bay showed that the mesozooplankton (<2 mm body width)

community included egg, larval, juvenile and adult stages of copepods, cladocerans, euphausiids, decapods,

chaetognaths, hydromedusae and salps, as well as protozoans and meroplankton larvae (Maartens 2003;

Hansen et al. 2005). Copepods are the most dominant group making up 70–85% of the zooplankton.

Seasonal patterns in copepod abundance, with low numbers during autumn (March–June) and increasing

considerably during winter/early summer (July–December), appear to be linked to the period of strongest

coastal upwelling in the northern Benguela (May–December), allowing a time lag of about 3–8 weeks, which

is required for copepods to respond and build up large populations (Hansen et al. 2005). This suggest close

coupling between hydrography, phytoplankton and zooplankton. Timonin et al. (1992) described three

phases of the upwelling cycle (quiescent, active and relaxed upwelling) in the northern Benguela, each one

characterised by specific patterns of zooplankton abundance, taxonomic composition and inshore-offshore

distribution. It seems that zooplankton biomass closely follows the changes in upwelling intensity and

phytoplankton standing crop. Consistently higher biomass of zooplankton occurs offshore to the west and

northwest of Walvis Bay (Barnard 1998).

Ichthyoplankton constitutes the eggs and larvae of fish. As the preferred spawning grounds of numerous

commercially exploited fish species are located off central and northern Namibia (Figure 4.8), their eggs and

larvae form an important contribution to the ichthyoplankton in the region. Phytoplankton, zooplankton and

ichthyoplankton abundances in the survey area will be seasonally high, with diversity increasing in the in the

vicinity of the confluence between the Angola and Benguela currents and west of the oceanic front and shelf-

break.

4.3.3 JELLYFISH

In recent years the abundance of large medusae jellyfish has increased along the Namibian coast.

In particular the hydrozoan Aequorea forskalea and the scyphozoan Chrysaora hysoscella have increased in

the northern Benguela (Brierley et al., 2001). It has been suggested that the biomass of jellyfish now

exceeds that of commercially valuable finfish (Lynam et al., 2006). The cause of this dramatic increase is

thought to reflect the fact that jellyfish have expanded to fill the niche which opened due to the

overexploitation of sardine and anchovy in the late 1960s (Bakun and Weeks, 2006).




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Figure 4.8: The proposed survey area in relation to major spawning areas in the central and

northern Benguela region (adapted from Cruikshank 1990; Hampton 1992).

4.3.4 CEPHALOPODS

On the basis of abundance and trophic links with other species, eight species of cephalopod have been

identified as being important within the Benguela system (Lipinski, 1992). A further five species show

potential as key cephalopod species (see Table 4.1).

The colossal squid, Mesonychoteuthis hamiltoni, and the giant squid, Architeuthis sp., both deep dwelling

species, could potentially occur in the pelagic habitats of the project area, although the likelihood of

encounter is extremely low. Growing to in excess of 10 m in length, they are the principal prey of the sperm

whale, and are also taken by beaked whaled, pilot whales, elephant seals and sleeper sharks. Nothing is

known of their vertical distribution, but data from trawled specimens and sperm whale diving behaviour

suggest they may span a depth range of 300 – 1 000 m.




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Table 4.1: Cephalopod species of importance or potential importance within the Benguela

System. After Lipinski (1992).

Scientific Name Importance

Important species:

Sepia australis Very abundant in survey catches, prey of many fish species. Potential for fishery

Loligo vulgaris reynaudii Fisheries exists, predator of anchovy and hake, prey of seals and fish.

Todarodes angolensis Fisheries exists (mainly by-catch), predator of lightfish, lanternfish and hake, prey of seals.

Todaropsis eblanae Some by-catch fishery, predator of lightfish and lanternfish, prey of seals and fish. Potential

for fishery.

Lycoteuthis lorigera Unconfirmed by-catch, prey of many fish species. Potential for fishery.

Octopus spp. Bait and artinisal fishery, prey of seals and sharks.

Argonauta spp. No fisheries, prey of seals.

Rossia enigmata No fisheries, common in survey catches.

Potentially important species:

Ommastrephes bartramii No fisheries

Abraliopsis gilchristi No fisheries

Todarodes filippovae No fisheries

Lolliguncula mercatoris No fisheries

Histioteuthis miranda No fisheries

4.3.5 FISH

Due to the cold temperate nature of the region, the fish fauna off the Namibian coast is characterised by a

relatively low diversity of species compared with warmer oceans. However, the upwelling nature of the

region results in huge biomasses of specific species that support an important and lucrative commercial

fishery off this coast (Hampton, 2001; Hampton et al., 1998).

4.3.5.1 Pelagic fish

Small pelagic species include the sardine/pilchard (Sadinops ocellatus), anchovy (Engraulis capensis), chub

mackerel (Scomber japonicus), horse mackerel (Trachurus capensis) and round herring (Etrumeus

whiteheadi). These species typically occur in mixed shoals of various sizes (Crawford et al. 1987) and

generally occur within the 200 m contour, although they may often be found very close inshore, just beyond

the surf zone. They spawn downstream of major upwelling centres in spring and summer, and their eggs

and larvae are subsequently carried up the coast in northward flowing waters. Historically, two seasonal

spawning peaks for pilchard occurred; the first from October to December in an inshore area between Walvis

Bay and Palgrave Point and the second from February to March near the 200 m isobath between Palgrave

Point and Cape Frio. However, since the collapse of the pilchard stock, spawning in the south has

decreased (Crawford et al. 1987). Recruitment success relies on the interaction of oceanographic events,

and is thus subject to spatial and temporal variability. Consequently, the abundance of adults and juveniles

of these small pelagic fish is highly variable both within and between species. The Namibian pelagic stock is

currently considered to be in a critical condition due to a combination of over-fishing and unfavourable

environmental conditions as a result of Benguela Niños.

Two species that migrate along the southern African West Coast following the shoals of anchovy and

pilchards are snoek Thyrsites atun and chub mackerel Scomber japonicas. Their appearance along the

Namibian coast are highly seasonal. Snoek are voracious predators occurring throughout the water column,

feeding on both demersal and pelagic invertebrates and fish. The abundance and seasonal migrations of




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chub mackerel are thought to be related to the availability of their shoaling prey species (Payne & Crawford

1989).

Large pelagic species include tunas, billfish and pelagic sharks, which migrate throughout the southern

oceans, between surface and deep waters (>300 m) and have a highly seasonal abundance in the

Benguela. Species occurring off Namibia include the albacore/longfin tuna Thunnus alalunga, yellowfin T.

albacares, bigeye T. obesus, and skipjack Katsuwonus pelamis tunas, as well as the Atlantic blue marlin

Makaira nigricans, the white marlin Tetrapturus albidus and the broadbill swordfish Xiphias gladius (Payne &

Crawford 1989). The distribution of these species is dependent on food availability in the mixed boundary

layer between the Benguela and warm central Atlantic waters. Concentrations of large pelagic species are

also known to occur associated with underwater feature such as canyons and seamounts as well as

meteorologically induced oceanic fronts (Penney et al. 1992).

A number of species of pelagic sharks are also known to occur off the southern African West Coast,

including blue Prionace glauca, short-fin mako Isurus oxyrinchus and oceanic whitetip sharks Carcharhinus

longimanus. Occurring throughout the world in warm temperate waters, these species are usually found

further offshore. Of these the blue shark is listed as “Near threatened”, and the short-fin mako, whitetip,

great white and whale sharks as “Vulnerable” on the International Union for Conservation of Nature (IUCN).

The inshore waters of the central and northern Namibian coastline are also home to a number of boney fish

and cartilagenous fish, many of which are popular angling species. These include the Silver kob

Argyrosomus inodorus, dusky kob Argyrosomus coronus, white steenbras Lithognathus lithognathus, West

Coast steenbras Lithognathus aureti, copper shark Carcharhinus brachyurus, the spotted gulley shark Triakis

megalopterus and the smoothhound Mustelus mustelus (Kirchner et al. 2000; Zeybrandt & Barnes 2001).

Warm water species that occur further north include garrick Lichia amia, shad Pomatomus saltatrix and

spotted grunter Pomadasys jubelini (Barnard 1998).

Spawning in silver kob occurs throughout the year but mostly in the warmer months from October to March

when water temperatures are above 15°C and large adult fish occur in the nearshore, particularly in the

identified spawning areas of Sandwich Harbour and Meob Bay. Adults are migratory whereas juveniles are

resident in the surf zone. The stock is exploited by the commercial linefishery (deck and skiboats) and

recreational shore angling and is regarded as overexploited and near collapse with less than 25% of pristine

spawner biomass remaining (Kirchner 2001; Holtzhausen et al. 2001). The juveniles and adolescents of

dusky kob are resident in the nearshore, and are especially abundant in the turbid plume off the Kunene

River Mouth and in selected surf zones of northern and central Namibia (Potts et al. 2010). The adults are

migratory according to the movement of the Angola-Benguela frontal zone, moving northwards as far as

Gabon in winter and returning to southern Angola and northern Namibia in spring where spawning occurs in

the offshore (Potts et al. 2010). The bulk of the population of both steenbrass species exists in the

nearshore at <10 m depth, with juveniles occurring in the intertidal surf zone. Spawning occurs in the surf

zone and eggs and larvae from both populations drift northwards (Holtzhausen 2000). Spawning habitats

are thought to be extremely limited and have yet to be clearly identified.

4.3.5.2 Demersal fish

As many as 110 species of bony and cartilaginous fish have been identified in the demersal communities on

the continental shelf of the southern African West Coast (Roel 1987). Changes in fish communities occur

with increasing depth (Roel 1987; Smale et al. 1993; Macpherson & Gordoa 1992; Bianchi et al. 2001;

Atkinson 2009), with the most substantial change in species composition occurring in the shelf break region

between 300 m and 400 m depth (Roel 1987; Atkinson 2009). Common commercial demersal species found

mostly on the continental shelf but also extending beyond 500 m water depth include both the shallow-water




EIA Report

October 2017

hake, Merluccuis capensis and the deep-water hake (Merluccius paradoxus), monkfish (Lophius vomerinus),

and kingklip (Genypterus capensis). There are also many other demersal “bycatch” species that include

jacopever (Helicolenus dactylopterus), angelfish/pomfret (Brama brama), kingklip (Genypterus capensis) and

gurnard (Chelidonichtyes sp), as well as several cephalopod species (such as squid and cuttlefishes) and

many elasmobranch (sharks and rays) species (Compagno et al. 1991).

Roel (1987) showed seasonal variations in the distribution ranges shelf communities, with species such as

the pelagic goby Sufflogobius bibarbatus, and West Coast sole Austroglossus microlepis occurring in shallow

water during summer only. The deep-sea community was found to be homogenous both spatially and

temporally. In a more recent study, however, Atkinson (2009) identified two long-term community shifts in

demersal fish communities; the first (early to mid-1990s) being associated with an overall increase in density

of many species, whilst many species decreased in density during the second shift (mid-2000s). These

community shifts correspond temporally with regime shifts detected in environmental forcing variables (Sea

Surface Temperatures and upwelling anomalies) (Howard et al. 2007) and with the eastward shifts observed

in small pelagic fish species and rock lobster populations (Coetzee et al. 2008, Cockcroft et al. 2000).

4.3.6 SEABIRDS

The Namibian coastline sustains large populations of breeding and foraging seabird and shorebird species,

which require suitable foraging and breeding habitats for their survival. In total, 11 species of seabirds are

known to breed along the southern Namibian coast, both on islands / guano platforms and in mainland

colonies (see Table 4.2). Most seabirds breeding in Namibia are restricted to areas where they are safe

from land predators, although some species are able to breed on the mainland coast in inaccessible places.

In general most breed on islands or on the man-made guano platforms in Walvis Bay, Swakopmund and

Cape Cross. The islands along the Namibian coast therefore provide a vital breeding habitat to most species

of seabirds that breed in Namibia. With the exception of Kelp Gull all the breeding species are listed Red

Data species in Namibia.

Most of the seabird species breeding in Namibia feed relatively close inshore (10-30 km). Cape Gannets,

however, are known to forage up to 140 km offshore (Dundee, 2006; Ludynia, 2007) and African Penguins

have also been recorded as far as 60 km offshore. The nesting grounds for Gannets and African Penguins

are at Ichaboe Island, Halifax and Possession Islands, which lie over 500 km to the south of the proposed

survey area.

Other Red-listed species found foraging or roosting along the coastline of Namibia are listed in Table 4.3.

Among the species present there are five species of albatrosses, petrels or giant-petrels recorded in the

waters off Namibia’s southern coast (Boyer & Boyer, in press). However, population numbers are poorly

known and they do not breed in Namibian waters.

Forty-nine species of pelagic seabirds have been recorded in the region, of which 14 are resident. Highest

pelagic seabird densities occur offshore of the shelf-break in winter.

In central Namibia, the 30 km long shoreline between Walvis Bay and Swakopmund has the highest linear

count of birds in southern Africa at approximately 450 birds/km with totals exceeding 13 000 shorebirds of 31

species, most of which are Palearctic migrants (Simmons et al., 1999; Molloy & Reinikainen, 2003;

http://www.ramsar.org/profile/profiles_namibia.htm). Individual 10 km sections, which include the rocky

shores between Caution Reef and Swakopmund peak even higher at 770 birds/km. Birds reported from the

30 km stretch of coast between Walvis Bay and Swakopmund include African Black Oystercatcher, Kelp

Gull, Cape cormorant, Turnstone (Arenaria interpres), Curlew Sandpiper (Calidris ferruginea), Grey plover

(Pluvialis squatarola), Swift Tern, Damara tern and Common Tern (Sterna hirundo) (Simmons et al., 1999).




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October 2017

The coastline between Walvis Bay and Cape Cross also boasts three man-made guano platforms: “Bird

Rock” north of Walvis Bay is 200 m offshore, whereas those north of Swakopmund and at Cape Cross have

been erected in salt pans. The platforms are unique in the world and currently produce about 2 500 tons of

guano per season. About 99% of the birds occurring on the platforms are Cape Cormorants, although

Whitebreasted Cormorants, Crowned Cormorants and Great White Pelicans also breed on the platforms

(http://www.namibweb.com/guano.htm; http://web.uct.ac.za/depts/stats/adu/walvisbay guano platform.htm).

The Kunene River mouth and its estuary at the border with Angola also serves as an extremely important

wetland for coastal birds, particularly the near threatened Damara Tern, which has been recorded in high

numbers (2 000 – 5 000) within and to the south of the mouth.

Table 4.2: Namibian breeding seabird species with their Namibian and global IUCN Red-listing

classification (from Kemper et al. 2007; Simmons & Brown in press).

Species Namibian Global IUCN

African Penguin Spheniscus demersus Endangered Vulnerable

Bank Cormorant Phalacrocorax neglectus Endangered Endangered

Cape Cormorant Phalacrocorax capensis Near Threatened Near Threatened

Cape Gannet Morus capensis Endangered Vulnerable

Crowned Cormorant Phalacrocorax coronatus Near Threatened Least Concern

African Black Oystercatcher Haematopus moquini Near Threatened Near Threatened

White-breasted cormorant Phalacrocorax carbo Least Concern Least Concern

Kelp Gull Larus dominicanus Least Concern Least Concern

Hartlaub's Gull Larus hartlaubii Vulnerable Least Concern

Swift Tern Sterna bergii bergii Vulnerable Least Concern

Damara Tern Sterna balaenarum Near Threatened Near Threatened

*In the IUCN scheme Endangered is a more extinction-prone class than Vulnerable and differences between Namibia and

global classifications are the result of local population size and the extent and duration of declines locally.

Table 4.3: Other Namibian Red-listed bird species with their Namibian and global IUCN Red-

listing classification (from Kemper et al. 2007; Simmons & Brown in press).

Species Namibian Global IUCN

Atlantic Yellow-nosed Albatross Thalassarche chlororhynchos Endangered Endangered

Black-browed Albatross Thalassarche melanophrys Endangered Endangered

Caspian Tern Sterna caspia Vulnerable Vulnerable

Greater Flamingo Phoenicopterus ruber Vulnerable Near Threatened

Lesser Flamingo Phoenicopterus minor Vulnerable Near Threatened

White-chinned Petrel Procellaria aequinoctialis Vulnerable Vulnerable

Chestnut-banded Plover Charadrius pallidus Near Threatened Least Concern

Northern Giant-Petrel Macronectes halli Near Threatened Near Threatened

Shy Albatross Thalassarche cauta Near Threatened Near Threatened

*In the IUCN scheme Endangered is a more extinction-prone class than Vulnerable, and differences between Namibia and

global classifications are the result of local population size, and the extent and duration of declines locally.




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October 2017

4.3.7 TURTLES

Five of the eight species of turtle worldwide occur off Namibia (Bianchi et al., 1999). However, the

Leatherback (Dermochelys coriacea) is the only turtle likely to be encountered regularly in the offshore

waters off Namibia. Observations of Green (Chelonia mydas), Loggerhead (Caretta caretta), Hawksbill

(Eretmochelys imbricata) and Olive Ridley (Lepidochelys olivacea) turtles in the area are rare. Leatherback

turtles are listed as Critically Endangered worldwide by the International Union for Conservation of Nature

(IUCN) and are in the highest categories in terms of need for conservation in the Convention on International

Trade in Endangered Species (CITES) and Convention on Migratory Species (CMS). Loggerhead and

Green turtles are listed as Endangered.

The Benguela ecosystem, especially the northern Benguela where jelly fish numbers are high, is increasingly

being recognised as a potentially important feeding area for Leatherback turtles from several globally

significant nesting populations in the south Atlantic (Gabon, Brazil) and south east Indian Ocean (South

Africa) (Lambardi et al., 2008, Elwen & Leeney, 2011; South Atlantic Sea Turtle Network (SASTN) meeting,

Swakopmund, Namibia, 24-30 July 2011). Leatherback turtles from the east South Africa population have

been satellite tracked swimming around to the West Coast of South Africa and Namibia (Lambardi et al.

2008). Although they tend to avoid nearshore areas, they may be encountered in Walvis Bay and off

Swakopmund between October and April when prevailing north wind conditions result in elevated seawater

temperatures (see Figure 4.9). Leatherback turtles have recently washed up in significant numbers on the

central Namibian shore. Their abundance in the study area is expected to be low.

Figure 4.9: The survey area (red polygon) in relation to the post-nesting distribution of nine

satellite tagged leatherback females (1996 – 2006; Oceans and Coast, unpublished

data).




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October 2017

4.3.8 MARINE MAMMALS

The marine mammal fauna off the Namibian coast comprises 32 species of cetaceans (whales and dolphins)

and five seal species.

4.3.8.1 Cetaceans

Thirty-two species of whales and dolphins are known (based on historic sightings or strandings records) or

likely (based on habitat projections of known species parameters) to occur in Namibian waters

(see Table 4.4). Apart from the resident species such as the endemic Heaviside’s dolphin, Bottlenose and

Dusky dolphins, Namibia’s waters also host species that migrate between Antarctic feeding grounds and

warmer breeding ground waters, as well as species with a circum-global distribution.

The distribution of cetaceans in Namibian waters can largely be split into those associated with the

continental shelf and those that occur in deep, oceanic water. Importantly, species from both environments

may be found in the continental slope (200 to 1 000 m) making this the most species-rich area for cetaceans.

Cetacean density on the continental shelf is usually higher than in pelagic waters, as species associated with

the pelagic environment tend to be wide ranging.

Cetaceans can be divided into two major groups, the mysticetes or baleen whales which are largely

migratory, and the toothed whales or odontocetes which may be resident or migratory.

Mysticetes / Baleen whales

The majority of mysticetes whales fall into the family Balaenidae. Those occurring in the study area include

the Blue, Fin, Sei, Antarctic Minke, Dwarf Minke, Bryde’s and Humpback whale. The majority of these

species occur in pelagic waters with only occasional visits to shelf waters. All of these species show some

degree of migration either to, or through, the latitudes encompassed by the proposed survey area when en

route between higher latitude (Antarctic or Subantarctic) feeding grounds and lower latitude breeding

grounds. Depending on the ultimate location of these feeding and breeding grounds, seasonality in

Namibian waters can be either unimodal, usually in winter months (June to September), or bimodal (e.g.

May-July and October-November) reflecting a northward and southward migration through the area.

Northward and southward migrations may take place at difference distances from the coast due to whales

following geographic or oceanographic features, thereby influencing the seasonality of occurrence at

different locations. Due to the complexities of the migration patterns, each species is discussed in further

detail below.

• Blue whales: Antarctic Blue whales were historically caught in high numbers during commercial

whaling activities, with a single peak in catch rates during July in Walvis Bay, Namibia and Namibe,

Angola suggesting that in the eastern South Atlantic these latitudes are close to the northern migration

limit for the species (Best, 2007). Acoustic detections of blue whales in the Antarctic peak between

December and January confirming this migration pattern (Tomisch et al. 2016). Only two confirmed

sightings of blue whales have occurred off the entire west coast of Africa since 1973 (Branch et al.,

2007), although search effort (and thus information) in Namibia and in pelagic waters is very low.

Several recent (2014-2015) sightings of blue whales have occurred during seismic surveys off the

southern part of Namibia in water >1 000 m deep confirming their current existence in the area and

occurrence in Autumn months. The probability of encounters in the survey area is expected to be low.




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October 2017

Table 4.4: List of cetacean species known (from historic sightings or strandings) or likely (habitat projections based on known species

parameters) to occur in Namibian waters. Likely occurrence in probable habitat (Shelf or Offshore) is indicated by ‘yes’, ‘no’ (unlikely),

‘edge’ (shelf edge 200-500 m depth) or ‘?’ (unknown).

Common name Species Shelf Offshore Seasonality IUCN Conservation Status

Delphinids

Dusky dolphin Lagenorhynchus obscurus Yes (0- 800 m) No Year round Least Concern

Heaviside’s dolphin Cephalorhynchus heavisidii Yes (0-200 m) No Year round Least Concern

Common bottlenose dolphin Tursiops truncatus Yes Yes Year round Least Concern

Common (short beaked) dolphin Delphinus delphis Yes Yes Year round Least Concern

Southern right whale dolphin Lissodelphis peronii Yes Yes Year round Data Deficient

Striped dolphin Stenella coeruleoalba No Yes Year round Least Concern

Long-finned pilot whale Globicephala melas Edge Yes Year round Data Deficient

Short-finned pilot whale Globicephala macrorhynchus No Yes Year round Data Deficient

Rough-toothed dolphin Steno bredanensis No Yes Year round Least Concern

Killer whale Orcinus orca Yes Yes Year round Data Deficient

False killer whale Pseudorca crassidens Occasional Yes Year round Data Deficient

Pygmy killer whale Feresa attenuata Occasional Yes Year round Data Deficient

Risso’s dolphin Grampus griseus Yes (edge) Yes ? Least Concern

Sperm whales

Pygmy sperm whale Kogia breviceps Edge Yes Year round Data Deficient

Dwarf sperm whale Kogia sima Edge ? ? Data Deficient

Sperm whale Physeter macrocephalus Edge Yes Year round Vulnerable




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October 2017

Common name Species Shelf Offshore Seasonality IUCN Conservation Status

Beaked whales

Cuvier’s Ziphius cavirostris No Yes Year round Least Concern

Arnoux’s Beradius arnouxii No Yes Year round Data Deficient

Southern bottlenose Hyperoodon planifrons No Yes Year round Not assessed

Layard’s Mesoplodon layardii No Yes Year round Data Deficient

True’s M. mirus No Yes Year round Data Deficient

Gray’s M. grayi No Yes Year round Data Deficient

Blainville’s M. densirostris No Yes Year round Data Deficient

Baleen whales

Antarctic Minke Balaenoptera bonaerensis Yes Yes Higher in Winter Data Deficient

Dwarf minke B. acutorostrata Yes Yes Year round Least Concern

Fin whale B. physalus Yes Yes MJJ & ON, rarely in

summer

Endangered

Blue whale B. musculus No Yes Higher in MJJ Endangered

Sei whale B. borealis Edge Yes MJ & ASO Endangered

Bryde’s (offshore) B. brydei Yes Yes Higher in Summer (JFM) Not assessed

Pygmy right Caperea marginata Yes ? Year round Data Deficient

Humpback Megaptera novaeangliae Yes Yes Year round, higher in

JJASON

Least Concern

Southern right Eubalaena australis Yes No Year round, higher in

JASON

Least Concern





off the coast of northern Namibia: EIA Report

October 2017

• Fin whales: Fin whales were historically caught off the coast of Namibia. A bimodal peak in the catch

data from South Africa suggests animals were migrating further north to breed (during May-June)

before returning to Antarctic feeding grounds (during August-October). Recent data available from

passive acoustic monitoring over a two-year period off the Walvis Ridge shows acoustic presence in

June-August (Thomisch et al. 2016), supporting observations from whaling records. The location of

the breeding ground (if any) and how far north it is remains a mystery (Best, 2007). Some juvenile

animals may feed year round in deeper waters off the shelf (Best, 2007). Four strandings have

occurred in between Walvis Bay and the Kunene River in the last decade (NDP unpubl. data) and

groups of 5-8 animals have been seen on multiple occasions on the coast either side of Lüderitz in

2014 and 2015 (NDP unpubl. data) confirming their contemporary occurrence in Namibian waters and

potential use of the upwelling areas for feeding. Encounters in the survey area may occur

• Sei whales: There is very little information on Sei whales in Namibian waters and most information on

the species from the southern African sub-region originates from whaling data from 1958-1963. Sei

whales spend time at high altitudes (40-50˚S) during summer months and migrate north through South

African waters to unknown breeding grounds further north (Best, 2007). Since whaling catches were

confirmed off both Congo and Angola, it is likely that they migrate through Namibian waters. Due to

their migration pattern, densities in the proposed survey area are likely to show a bimodal peak with

numbers predicted to be highest in May and June, and again in August, September and October. All

whales were historically caught in waters deeper than 200 m with most catches from deeper than

1 000 m (Best & Lockyer, 2002). There is no current information on the abundance or distribution of

this species in the region, but a recent sighting of sei whales in March 2012 (NDP unpublished data)

and a live stranding in July 2013 in Walvis Bay (NDP unpublished data) confirms their contemporary

and probably year round occurrence on the Namibian continental shelf and beyond. Encounters in the

survey area are likely to occur.

• Bryde’s whales: Two genetically and morphologically distinct populations of Bryde’s whales live off the

coast of southern Africa (Best 2001). The “offshore population” lives beyond the shelf (> 200 m depth)

off west Africa and migrates between wintering grounds off equatorial west Africa (Gabon) and

summering grounds off western South Africa. Its seasonality within Namibian waters is thus opposite

to the majority of the balaenopterids with abundance likely to be highest in the broader potential

impact zone in January - March. The “inshore population” of Bryde’s whales is unique amongst

baleen whales in the region by being non-migratory. It lives on the continental shelf and Agulhas Bank

of South Africa ranging from approximately Durban in the east to at least St Helena Bay off the west

coast. It may move further north into the Benguela current areas of the west of coast of South Africa

and Namibia, especially in the winter months (Best 2007). A recent live stranding of a calf of this

population near Walvis Bay confirms the current occurrence of this population in Namibian waters. An

additional live sighting in the Namibian Islands Marine Protected Area (MPA) and in the third stranding

of a Bryde’s whale adult in April 2013 have not been assigned to population but indicate regular, year

round occurrence of the species in the northern Benguela ecosystem (NDP unpubl. data). Encounters

in the survey area are likely to occur.

• Minke whales: Two forms of Minke whale occur in the southern Hemisphere, the Antarctic Minke

whale and the Dwarf Minke whale; both species may occur within Namibian waters (Best 2007).

Antarctic Minke whales range from the pack ice of Antarctica to tropical waters and are usually seen

more than approximately 50 km offshore. Although adults of the species do migrate from the Southern

Ocean (summer) to tropical/temperate waters (winter) where they are thought to breed, some animals,

especially juveniles, are known to stay in tropical/temperate waters year round. Regular sightings of

semi-resident Antarctic Minke whales in Lüderitz Bay, especially in summer months (December -

March) and a stranding of a single animal in Walvis Bay (in Feb 2014) confirm the contemporary

occurrence of the species in Namibia (NDP unpubl. data). Recent data available from passive





October 2017

acoustic monitoring over a two-year period off the Walvis Ridge shows acoustic presence in June -

August and November - December (Thomisch et al. in press), supporting observations from whaling

records. The Dwarf Minke whale has a more temperate distribution than the Antarctic Minke and they

do not range further south than 60-65°S. Dwarf Minke whales have a similar migration pattern to

Antarctic Minkes with at least some animals migrating to the Southern Ocean in summer months.

Around southern Africa, Dwarf Minke whales occur closer to shore than Antarctic Minkes and have

been seen <2 km from shore on several occasions around South Africa. Both species are generally

solitary and densities are likely to be low in the survey area, but encounters may occur.

• Pygmy Right whale: The Pygmy Right whale, the smallest of the baleen whales, occurs in Namibian

waters and has a history of stranding within or near Walvis Bay. The species is typically associated

with cool temperate waters between 30°S and 55°S and records in Namibia are the northern most for

the species with no confirmed records north of Walvis Bay, so it is unlikely to occur in the survey area.

• Southern Right whales: The most abundant baleen whales off the coast of Namibia are Southern

Right and Humpback whales. The southern African Southern Right whale population historically

extended from southern Mozambique (Maputo Bay) to southern Angola (Baie dos Tigres). In the last

decade, both southern right whales and Humpback whales have been increasingly observed to remain

on the West Coast of South Africa well after the typical South African 'whale season' of June-

November, sometimes staying as late as February where they have been observed feeding in

upwelling zones, especially Saldanha and St Helena Bays (Barendse et al. 2011; Mate et al. 2011). In

Namibian waters, humpback whales have similarly been seen ‘out of season’ (i.e. March-April) (NDP

unpublished data) and Southern Right whales have also been sighted in all months of the year

(J-P. Roux, pers. comm). This suggests that these species have a year round occurrence in Namibian

waters, with a peak in late winter months associated with the annual migration of the majority of the

populations.

The most recent abundance estimate for Southern Rights (2008) puts the population at approximately

4 600 individuals of all age and sex classes, which is thought to be at least 23% of the original

population size (Brandaõ et al., 2011). Since the population is still continuing to grow at approximately

7% per year (Brandaõ et al. 2011), the population size in 2016 would number more than 8 000

individuals. When the population numbers crashed, the range contracted down to just the south coast

of South Africa, but as the population recovers, it is repopulating its historic grounds, including

Namibia (Roux et al. 2001) and Mozambique (Banks et al. 2011).

Southern Right whales are seen regularly in Namibian coastal waters (<3 km from shore), especially in

the southern half of the Namibian coastline between Conception Bay and Chameis Bay (Roux et al.

2001; 2011), although some have been reported as far north as the Kunene and Möwe Bay (Roux et

al. 2015.). Southern Right whales have been recorded in Namibian waters in all months of the year (J-

P Roux pers. comm., NDP unpublished data), but with numbers peaking in winter (June - September)

(Best 1994; Roux et al. 2001). A secondary peak in summer (December - January) also occurs,

associated with animals feeding off the west coast of South Africa (and possibly Namibia) and

performing exploratory trips into southern Namibia (NDP unpubl. data).

Animals photographed in Namibia have recently been shown to be a part of the southern African

population, which breeds predominantly off the southern Cape coast (Roux et al., 2015). Although

most Southern Right whales are thought to hug the shore when around southern Africa, it has recently

been proposed, based on a review of historic whaling data and sightings in Namibian water, that some

animals may be foraging in the upwelling cells of the Benguela ecosystem, which reach up to 200 km

offshore (Roux et al. 2015). Due to the distance from shore and low latitude of the survey area,

encounters with southern right whales are unlikely to occur.





October 2017

• Humpback whales: The majority of Humpback whales passing the coast of Namibia are those

migrating to breeding grounds off tropical west Africa, between Angola and the Gulf of Guinea

(Rosenbaum et al. 2009; Barendse et al. 2010). A recent synthesis of available humpback whale data

from Namibia (Elwen et al. 2014) shows that in coastal waters, the northward migration stream is

larger than the southward peak. This supports previous suggestions that animals migrating north

strike the coast at varying places mostly north of St Helena Bay (South Africa) resulting in increasing

whale density on shelf waters moving north towards Angola, but no clear migration ‘corridor’. Thus

humpback whales appear to be spread out widely across the shelf and into deeper pelagic waters

(Barendse et al. 2010; Best & Allison 2010; Elwen et al. 2014). There is evidence from satellite tagged

animals and the smaller secondary peak in numbers in Walvis Bay, that many humpback whales on

their southern migration follow a more offshore route along the Walvis Ridge, which is directly across

the survey area, while others follow a more coastal route (including the majority of mother-calf pairs)

possibly lingering in the feeding grounds off West South Africa in summer (Elwen et al. 2014;

Rosenbaum et al. 2014).

Recent abundance estimates put the number of animals in the west African breeding population to be

in excess of 9 000 individuals in 2005 (IWC 2012) and it is likely to have increased since this time at

about 5% per annum (IWC 2012). Humpback whales are thus likely to be the most frequently

encountered baleen whale in the survey area, ranging from the coast out beyond the shelf, with year

round presence but numbers peaking in July – October associated with the breeding migration. It is

important to note that mother-calf pairs are usually the last animals to migrate away from calving

grounds and thus pass through Namibian waters. Although these animals often stay close to shore,

they are still likely to be the dominant social class observed from September onwards in Namibian

waters. Travelling baleen whales and especially mother-calf groups tend to be acoustically quiet

(possibly to minimise detection by killer whales) and are thus very challenging to detect at night even

with the implementation of Passive Acoustic Monitoring (PAM). Humpback whales are the most likely

baleen whale to be encountered.

Odontocetes

The Odontoceti are a varied group of animals including the dolphins, porpoises, beaked whales and sperm

whales. Those occurring in the study area are discussed below.

• Killer whales (Orcinus orca) have a circum-global distribution being found in all oceans from the

equator to the ice edge (Best 2007). Killer whales occur year round in low densities off western South

Africa (Best et al. 2010), Namibia (Elwen & Leeney 2011) and in the Eastern Tropical Atlantic (Weir et

al. 2010). Killer whales are found in all depths from the coast to deep open ocean environments and

may thus be encountered in the survey area at low levels.

• The False Killer whale has a tropical to temperate distribution and most sightings off southern Africa

have occurred in water deeper than 1 000 m but with a few close to shore as well (Findlay et al. 1992;

NDP Unpubl. data). False killer whales usually occur in groups ranging in size from 1-100 animals

(mean 20.2) (Best 2007), and are thus likely to be fairly easily seen in most weather conditions. There

is no information on population numbers of conservation status and no evidence of seasonality in the

region (Best 2007).

• Long-Finned Pilot whales: Long-finned pilot whales display a preference for temperate waters and are

usually associated with the continental shelf or deep water adjacent to it (Mate et al., 2005; Findlay et

al. 1992, Weir, 2011). They are regularly seen associated with the shelf edge by marine mammal

observers, fisheries observers and researchers operating in Namibian waters (NDP unpublished data).

The distinction between Long-finned and Short finned (G. macrorhynchus) Pilot whales is difficult to

make at sea. As the latter are regarded as more tropical species (Best, 2007), it is likely that the vast





October 2017

majority of pilot whales encountered in the Namibian waters are long-finned. However, due to the low

latitude and offshore nature of the survey, it is likely that both species could be encountered in the

survey area.

• Sperm whales: Sperm whales are the largest of the toothed whales and have a complex, structured

social system with adult males behaving differently to younger males and female groups. They live in

deep ocean waters, usually greater than 1 000 m depth, although they occasionally come into waters

500 to 200 m deep on the shelf (Best, 2007). They are relatively abundant globally (Whitehead,

2002), although no estimates are available for the subregion. Seasonality of historical catches off

west South Africa suggests that medium and large sized males are more abundant in winter months,

while female groups are more abundant in autumn (March-April), although animals occur year round

(Best, 2007). Sperm whales were one of the most frequently seen cetacean species during a series of

observations made from offshore seismic survey vessels operating between Angola and the Gulf of

Guinea. All sightings were made in water deeper than 780 m, and numbers peaked during April –

June (Weir 2011). In contrast, sightings of sperm whales by Marine Mammal Observers (MMOs) on

seismic vessels operating in Namibia are low. Sperm whales feed at great depths during dives in

excess of 30 minutes making them difficult to detect visually. The regular echolocation clicks made by

the species when diving, however, make them relatively easy to detect acoustically using PAM. The

proposed survey should be largely inshore of the expected range of sperm whales and sightings in the

survey area are expected to be very low.

• The genus Kogia currently contains two recognised species, the dwarf and pygmy sperm whales.

There is preliminary evidence of species level genetic differentiation between dwarf sperm whale

populations in the Indian and Atlantic Oceans (Chivers et al. 2004). Due to their small body size,

cryptic behaviour, low densities and small school sizes, these whales are difficult to observe at sea,

and morphological similarities make field identification to species level problematic. The majority of

what is known about Kogiid whales in the southern African subregion results from studies of stranded

specimens (e.g. Findlay et al. 1992; Plön 2004; Elwen et al. 2013). There are >30 records of

Pygmy Sperm whales collected along the Namibian coastline with a peak in strandings in June and

August. A single account of Dwarf Sperm whale collected in Walvis Bay in 2010, demonstrates that

this species also occurs in Namibian waters (Elwen et al. 2013) and as a warm water specialist is

likely to occur within the survey area.

• Dusky dolphin: Dusky dolphins are likely to be the most frequently encountered small cetacean in

water less than 500 m deep. This species is resident year round throughout the Benguela ecosystem

in waters from the coast to at least 500 m deep (Findlay et al., 1992). Although no information is

available on the size of the population, they are regularly encountered in near shore waters off South

Africa and Lüderitz, although encounters near-shore are rare along the central Namibian coast (Walvis

Bay area), with most records coming from beyond 5 nm from the coast (Elwen et al. 2010a; NDP

unpubl. data). In a recent survey of the Namibian Islands Marine Protected Area (between latitudes of

24˚29’ S and 27˚57’ S and depths of 30-200 m) dusky dolphins were the most commonly detected

cetacean species with group sizes ranging from 1 to 500 individuals (NDP unpublished data), although

group sizes up to 800 have been reported in southern African waters (Findlay et al,. 1992).

• Heaviside’s dolphin: Heaviside’s dolphins are relatively abundant in the southern Benguela ecosystem

within the region of 10 000 animals estimated to live in the 400 km of coast between Cape Town and

Lamberts Bay (Elwen et al., 2009) and several hundred animals living in the areas around Walvis Bay

and Lüderitz. This species occupies waters from the coast to at least 200 m depth (Elwen et al., 2006;

Best, 2007), and may show a diurnal onshore-offshore movement pattern, although this varies

throughout the range. The survey is likely to be predominantly offshore of the known species range

and encounters are unlikely.





October 2017

• Common dolphin: The Common dolphin is known to occur offshore in Namibian waters (Findlay et al.,

1992). A recent stranding in Lüderitz (May 2012, NDP unpublished data) and marine mammal

observer reports have confirmed their occurrence in the region. The extent to which they occur in the

proposed survey area is currently unknown. Although group sizes can be large, averaging 267 for the

southern African region (Findlay et al,. 1992), 92 for Angola (Weir 2011) and 37 in Namibia (NDP

unpubl. data). They are more frequently seen in the warmer waters offshore and to the north of the

country. Encounter rate in the survey area are not known.

• Common Bottlenose dolphin: Common Bottlenose dolphins are widely distributed in tropical and

temperate waters throughout the world, but frequently occur in small (10s to low 100s) isolated coastal

populations. Within Nambian waters two populations of bottlenose dolphins occur. A small population

inhabits the very near shore coastal waters (mostly <15m deep) of the central Namibian coastline from

approximately Lüderitz in the south to at least Cape Cross in the north. Although the population is

thought to number less than 100 individuals (Elwen et al. 2011), its nearshore habitat makes it unlikely

to be impacted by the current seismic survey. An offshore 'form' of common bottlenose dolphis occurs

around the coast of southern Africa including Namibia and Angola (Best 2007) with sightings restricted

to the continental shelf edge and deeper. Offshore bottlenose dolphins frequently form mixed species

groups, often with pilot whales or Risso's dolphins.

Several other species of toothed whales that might occur in the deeper waters of survey area at low levels

include the Pygmy Killer whale, Risso’s dolphin, Striped and Right Whale dolphins, and Cuvier’s and

Layard’s beaked whales (Findlay et al. 1992; Best 2007). Nothing is known about the population size or

density of these species in the survey area but it is likely that encounters would be rare (Findlay et al. 1992;

Best 2007).

4.3.8.2 Pinnipeds

The Cape Fur seal (Arctocephalus pusillus pusillus) is the only species of seal resident along the West Coast

of Africa. Vagrant records from four other species of seal more usually associated with the subantarctic

environment have also been recorded: southern elephant seal (Mirounga leoninas), subantarctic fur seal

(Arctocephalus tropicalis), crabeater (Lobodon carcinophagus) and leopard seals (Hydrurga leptonyx) (David

1989).

The Cape Fur seal is common along the Namibian coastline, occurring at numerous breeding sites on the

mainland and on nearshore islands and reefs. Atlas Bay, Wolf Bay and Long Islands (near Lüderitz)

together represent the largest breeding concentration (about 68 000 pups) of seals in Namibia. Currently the

largest breeding site in Namibia is at Cape Cross north of Walvis Bay (see Figure 4.10) where about 51 000

pups are born annually (Ministry of Fisheries and Marine Resources unpubl. data). The colony supports an

estimated 157 000 adults (Hampton 2003), with unpublished data from Marine and Coastal Management

(MCM, South Africa) suggesting a number of 187 000 (Mecenero et al. 2006). A further colony of

approximately 9 600 individuals exists on Hollamsbird Island, approximately 120 km south of Sandwich

Harbour. There are also seal colonies at Cape Frio and Möwe Bay, which are located approximately 60 km

and 200 km south of the proposed survey area, respectively. The colony at Pelican Point is primarily a haul-

out site. The mainland seal colonies present a focal point of carnivore and scavenger activity in the area, as

jackals and hyena are drawn to this important food source.

Seals are highly mobile animals with a general foraging area covering the continental shelf up to 120 nm

(~220 km) offshore, with bulls ranging further out to sea than females. The timing of the annual breeding

cycle is very regular occurring between November and January. Breeding success is highly dependent on





October 2017

the local abundance of food, territorial bulls and lactating females being most vulnerable to local fluctuations

as they feed in the vicinity of the colonies prior to and after the pupping season (Oosthuizen, 1991).

There is a controlled annual quota, determined by government policy, for the harvesting of Cape Fur seals

on the Namibian coastline. The Total Allowable Catch (TAC) currently stands at 60 000 pups and 5 000

bulls, distributed among four licence holders (DHI, 2007). The seals are exploited mainly for their pelts

(pups), blubber and genitalia (bulls) (Molloy & Reinikainen, 2003).

4.4 Socio-ECONOMIC ENVIRONMENT

This section provides a description of the human utilisation and activities off the coast of Namibia that may

be affected by or have an effect on the proposed seismic survey programme.

Figure 4.10: Project - environment interaction points in central Namibia, illustrating conservation

areas, seal colonies and seabird breeding areas in the coastal region. Location of the

survey area is also shown.





October 2017

4.4.1 FISHERIES

4.4.1.1 Overview of fisheries

Since the survey area occurs on the Namibia / Angola border, a brief overview of both countries is provided

below.

Namibia

The Namibian fishing industry is the country’s second largest earner of foreign currency and the third largest

economic sector in terms of contribution to the Gross Domestic Product (GDP). Supported by the high

productivity of the Benguela upwelling ecosystem, abundant fish stocks typify Namibian waters. Fish

resources in upwelling systems are typically high in biomass and relatively low in diversity. The Namibian

fisheries have focused on demersal species, small pelagic species, large migratory pelagic fish, line-fish and

crustacean resources. Mariculture production is a developing industry based predominantly in Walvis Bay

and Lüderitz Bay and surrounds.

The commercial fishing sectors that operate off the coast of Namibia include:

• Demersal trawl

• Mid-water trawl

• Deep-water trawl

• Small pelagic purse-seine

• Large pelagic long-line

• Demersal long-line

• Tuna pole

• Line-fish

• Deep-sea crab

• Rock lobster

Namibia has only two major fishing ports from which all the main commercial fishing operations are based

namely, Walvis Bay and Lüderitz. In central Namibia, the major port is Walvis Bay and it is from here that

the majority of fishing vessels operate. Most of the fishing conducted from this port is, for economic and

logistic reasons, directed mostly at fishing grounds in the central and northern part of Namibia and to a lesser

extent the southerly fishing grounds. A significant amount of fishing activity also takes place from Lüderitz

(which is located close to the northern extent of the proposed survey area) where hake trawlers and long-

liners operate, as well as a small rock lobster fishery.

Angola

The Angolan fisheries sector represents about 1.7% of the GDP of Angola, ranked second in importance to

the national economy after oil and mining. The Angola Current with its warm water from the north and the

cold Benguela Current in the south creates a strong upwelling with a high productive ecosystem for marine

resources.

The Southern Fishing Zone (Lobito to the Kunene River) is the most productive of Angola’s three fishing

zones, with an abundance of horse mackerel, sardines (pilchard), tunas and a range of demersal species

including hake. In 2012, the overall production from marine fisheries was estimated at about 277 000

tonnes, of which the catch of small pelagic species represented about half.

The commercial fishing sectors that operate off the southern Angolan coast include:

• Finfish Trawl (equivalent to demersal trawl)

• Large pelagic long-line

• Crustacean trawl (equivalent to crab trap)

Industrial and semi-industrial fishing vessels utilise ports at Luanda, Kwanza Sul, Benguela and Namibe,

approximately 70% of catch being offloaded in Luanda. Many marine artisanal fishers do not have a fixed

place for disembarking catches, as many fishers follow the fish along the coast and most artisanal craft can

be brought ashore anywhere on the sandy beaches.





October 2017

4.4.1.2 Demersal trawl

Namibia

The demersal trawl sector targets primarily hake (Merluccius capensis and M. paradoxus). Main by-catch

species include monkfish (Lophius spp.), kingklip (Genypterus capensis) and snoek (Thyrsites atun). A fleet

of about 100 Namibian-registered trawlers operate along the whole Namibian coastline (17ºS to 30ºS)

following the distribution of hake along the continental shelf.

This fishery operates along the shelf contours between depths of 200 m and 850 m. Trawlers are prohibited

from operating inshore of the 200 m isobath. The hake-directed trawl fishery is Namibia’s most valuable

fishery with a current annual hake TAC of 140 000 tons (2015/16). The fishery is closed each year for the

month of October (which coincides with the key spawning period).

The distribution of hake-directed demersal trawl fishing grounds in relation to the proposed survey area is

shown in Figure 4.11. Based on commercial fishing records, trawling activity would be expected within the

proposed survey area between the 250 m and 600 m isobaths. The average number of trawls expended on

a monthly basis by the demersal trawl fleet nationally and within the proposed survey area is shown in

Figure 4.12. The proposed survey (which includes the maximum zone of disturbance) covers approximately

2 921 km2 or 3.5% of the total trawlable ground available to the sector. Annual effort expended within the

survey area amounts to approximately 3 598 fishing hours (2.4% of the total) and catch taken amounts to

3 538 tons (3.7% of the total).

Demersal trawlers are segregated into wet and freezer vessels which differ in terms of the capacity for the

processing of fish offshore (at sea) and in terms of vessel size and capacity. Trawlers vary from 35 m to

90 m in length, with a shaft power of 750 to 3 000 kW. Wetfish vessels are generally smaller than freezer

vessels and do not range as far offshore. While freezer vessels may work in an area for up to a month at a

time, wetfish vessels fish for about seven days before returning to port.

Trawl gear configurations are similar for both freezer and wetfish vessels (see Figure 4.13). Typical demersal

trawl gear configuration consists of:

• Steel warps up to 32 mm diameter (in pairs up to 3 km long when towed);

• A pair of trawl doors (500 kg to 3 tons each);

• Net footropes which may have heavy steel bobbins attached (up to 24" diameter), as well as large

rubber rollers (“rock-hoppers”); and

• Net mesh (diamond or square shape) is normally wide at the net opening whereas the bottom end of

the net (or cod-end) has a 130 mm stretched mesh.

Generally, trawlers tow their gear at 3.5 knots for up to four hours per drag, and hake-directed trawling

occurs mainly from sunrise to sunset. When towing gear, the distance of the trawl net from the vessel is

usually 2 to 3 times the water depth. The horizontal net opening may be up to 50 m in width and 10 m in

height.

Angola

The Angolan demersal trawl fisheries fall into two major groups, those targeting demersal finfish (active

along the entire coastline) and those targeting demersal prawns and shrimps (active in the northern and

central fishing zones). The majority of landings by the demersal trawl fishery targeting finfish (hake and

seabreams) are recorded in the province of Luanda with less than 1% recorded in the southern province of

Namibe. It is probable that demersal trawl vessels would be encountered in Angolan waters if the survey

vessel enters Angolan waters during line turns.





October 2017

Figure 4.11: Survey area in relation to hake-directed demersal trawl catch (1992 – 2010) off the

Namibian coast.

Figure 4.12: The average number of trawls expended on a monthly basis by the demersal trawl

fleet nationally and within the proposed survey area (2004 – 2010).

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October 2017

Figure 4.13: Schematic diagram of trawl gear typically used by the Namibian hake trawl vessels.

4.4.1.3 Mid-water trawl

Namibia

The mid-water trawl fishery targets adult horse mackerel (Trachurus capensis). This fishery has the highest

volume and catch of all Namibian fish stocks, and in terms of economic value is the second highest

contributor behind the Cape hake fisheries. Maximum historical catches were reported during the 1980s but

catch rates have since declined. The TAC for 2013 was 350 000 tons and there are currently 67 rights-

holders registered within the fishery. Sixteen vessels are licenced to trawl for horse-mackerel in Namibia.

The mid-water trawl fleet operates exclusively out of the port of Walvis Bay and fishing grounds extend north

of 25ºS up to the border of Angola and effort is highest in the north. Juvenile Cape horse mackerel move

into deeper water when mature and are fished mostly between the 200 m and 500 m isobaths towards the

shelf break. The distribution of horse mackerel-directed fishing grounds in relation to the proposed survey

area is shown in Figure 4.14. Based on commercial fishing records, trawling activity would be expected

within the proposed survey area between the 200 m and 1000 m isobaths. The proposed survey (which

includes the maximum zone of disturbance) covers approximately 5 787 km2 or 17.3% of the total trawlable

ground available to the sector. The average monthly catch of horse mackerel taken nationally and from the

proposed survey area is shown in Figure 4.15. Annual effort expended within the survey area amounts to

approximately 3 553 fishing hours (22.9% of the total) and catch taken amounts to 32 194 tons (17.1% of the

total).

Trawl gear configuration is shown in Figure 4.16. Trawl warps are heavy ranging from 32 mm to 38 mm in

diameter. Net openings range from 40 m to 80 m in height and up to 120 m in width. Once gear is deployed

the vessel is hampered in its ability to manoeuvre as gear may extend up to 1 km astern of the vessel

(depending on the depth being fished).

The target catch species is meso-pelagic and shoals migrate vertically upwards through the water column

between dusk and dawn. Mid-water trawlers exploit this behaviour (diurnal vertical migration) by adjusting

the depth at which the net is towed (this typically varies from 400 m to just below the water surface).

Trawl warps (steel wire rope)

Doors (<3 000 kg)

Spread 100 m +

Headrope

Trawl net Codend





October 2017

Angola

In Angolan waters, adult horse mackerel is targeted by the pelagic trawl fleet, which comprises large steel,

mid-water stern trawlers. Catch reports suggest that fishing effort is highest in northern and central Angolan

waters and that the fishery is not active in the Namibe province or in the vicinity of the proposed survey area.

Figure 4.14: Survey area in relation to horse mackerel mid-water trawl catch (1997 – 2011) off the

Namibian coast.

Figure 4.15: The average monthly catch of horse mackerel taken nationally and from the proposed

survey area (2004 – 2011).

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October 2017

Figure 4.16: Mid-water trawl gear configuration.

4.4.1.4 Deep-water trawl

The deep-water trawl fishery is a small fishing sector directed at the outer Namibian shelf from 400 to

1 500 m water depth targeting orange roughy (Hoplostethus atlanticus) and alfonsino (Beryx splendens).

In Namibia the orange roughy fishery is split into four Quota Management Areas (QMAs) referred to as

“Hotspot”, “Rix”, “Frankies” and “Johnies”, none of which overlap with the proposed survey area (see

Figure 4.17). Almost no fishing for this species takes place outside of the designated QMA’s.

Fishing grounds were discovered in 1995/1996 and total catches reached 15 500 tons in 1997. Following a

drop in biomass levels, the TAC was decreased from 12 000 tons in 1998 to 1 875 tons in 2000. The fishery

has been closed since 2007.

The gear configuration of the deep-water trawl fishery is similar to that of demersal hake-directed trawlers

(see Figure 4.13).

4.4.1.5 Small pelagic purse-seine

Namibia

The pelagic purse-seine fishery, which targets Benguela sardine (Sardinops sagax) and juvenile horse

mackerel, was historically the largest fishery (by volume) in Namibia. The fishery started in 1947 and

operated predominantly from the port of Walvis Bay. The fishery grew rapidly until 1968 when the fish stock

collapsed. Fishing continued thereafter at a low level of effort, but the resource has not recovered. Namibia

has permitted a small fishery to continue to operate with limited catch. It has since been reopened with

a very low allowable catch (the 2016 TAC for pilchard was set at 14 000 t).

Fishing activity occurs primarily northwards of Walvis Bay to the Angolan border, inshore of the 200 m

isobath (see Figure 4.18). The proposed survey area (including the maximum zone of disturbance) covers

approximately 489 km2 or 0.7% of the fishing grounds used by the small pelagic purse-seine fishery.

Average annual catch within the area of operation between 1996 and 2011 amounts to approximately 0.2%

of the total catch landed nationally.





October 2017

Figure 4.17: Survey area in relation to catch positions and Quota Management Areas of the deep-

water trawl fishery targeting orange roughy (1994 to 2007). Note that the fishery is

currently closed.

Figure 4.18: Survey area in relation to small pelagic purse-seine catch (1996 – 2011).





October 2017

The fleet consists of approximately 36 wooden, glass-reinforced plastic and steel-hulled vessels ranging in

length from 21 m to 48 m. The targeted species are surface-shoaling and once a shoal has been located the

vessel encircle it with a large net (see Figure 4.19), which has a depth of 60 m to 90 m. Netting walls

surround aggregated fish both from the sides and from underneath, thus preventing them from escaping by

diving downwards. The nets framed by lines: a float line on top and lead line at the bottom. Once the shoal

has been encircled the net is pursed and hauled in and the fish are pumped onboard into the hold of the

vessel. It is important to note that after the net is deployed the vessel has no ability to manoeuvre until the

net has been fully recovered on-board and this may take up to 1.5 hours.

Figure 4.19: Schematic of typical purse-seine gear deployed in the “small” pelagic fishery.

Angola

The purse-seine industry for small pelagic species is the largest of the Angolan fisheries with respect to

landings, targeting juvenile Kunene horse mackerel, with a varying by-catch of Cape horse mackerel, round

sardinella and Madeiran sardinella. The fishery is predominantly active within northern and central fishing

grounds and is not expected to be active in the Namibe province. The Angolan purse-seine fishery is

therefore not expected to be impacted by the proposed survey.

4.4.1.6 Large pelagic long-line

Namibia

This sector utilises surface long-lines to target migratory pelagic species including albacore tuna (Thunnus

alalunga), yellowfin tuna (T. albacares), bigeye tuna (T. obesus), swordfish (Xiphias gladius) and various

shark species. Commercial landings of these species varies and can be as high as 6 000 tons per annum.

The spatial distribution of fishing effort is widespread and may be expected predominantly along the shelf

break between the 500 m and 2 000 m isobaths (see Figure 4.20). Effort occurs year-round with lower levels

of fishing effort expected between June and October (see Figure 4.21). Over the period 2008 to 2013, 7.1%

of the total effort expended by the fishery coincided with the proposed survey area (which includes the

maximum zone of disturbance), which is equivalent to an average of 58 lines per year (130 000 hooks).





October 2017

Catch taken within the proposed survey area amounted to approximately 146 tonnes per year (i.e. 6.4% of

the total catch landed by the sector).

Pelagic long-line vessels set a drifting mainline, which are up to 100 km in length. The mainline is kept near

the surface or at a certain depth by means of buoys (connected via “buoy-lines”), which are spaced

approximately 500 m apart along the length of the mainline (see Figure 4.22). Hooks are attached to the

mainline on relatively short sections of monofilament line (“snoods”) which are clipped to the mainline at

intervals of 20 to 30 m. A single main line consists of twisted tarred rope (6 to 8 mm diameter), bylon

monofilament (5 to 7.5 mm diameter) or braided monofilament (6 mm diameter). Various types of buoys are

used in combinations to keep the mainline near the surface and locate it should the line be cut or break for

any reason. Each end of the line is marked by a Dahn Buoy and Radar reflector, which marks it’s position

for later retrieval by the fishing vessel. A line may be left drifting for up to 18 hours before retrieval by means

of a powered hauler at a speed of approximately 1 knot. During hauling a vessel’s manoeuvrability is

severely restricted and, in the event of an emergency, the line may be dropped to be hauled in at a later

stage.

Figure 4.20: Survey area in relation to pelagic long-line effort off the coast of Namibia (2008 -

2013).

Angola

Large pelagic species are caught seasonally in Angolan waters with most of the fishing activity taking place

in the southern fishing grounds. Thus it is highly likely that fishing vessels and set lines would be

encountered across the maritime border in Angolan waters.





October 2017

Figure 4.21: Monthly average catch and effort recorded within the large pelagic long-line sector

within Namibian waters (2008 – 2013).

Figure 4.22: Typical pelagic long-line gear configuration.

4.4.1.7 Demersal long-line

Namibia

The demersal long-line fishery targets bottom-dwelling species, predominantly hake (Merluccius capensis

and M. paradoxus). Approximately 18 vessels are currently operating within the sector within three broad

areas. Vessels based in Lüderitz work south of 26°S towards the South Africa border while those based in

Walvis Bay operate between 23°S and 26°S and North of 23°S. A total hake TAC of 140 000 tons was set

for 2015/16, but less than 10 000 tons is caught by long-line vessels.

Fishing grounds extend along the entire Namibian coastline following the distribution of hake along the

continental shelf at a depth range of approximately 200 m to 600 m (see Figure 4.23). Fishing activity would

be expected throughout the survey area between these depths. Vessels operate year-round but operations

are particularly low in October and peak during December (see Figure 4.24). The proposed survey (which

includes the maximum zone of disturbance) covers approximately 2 278 km2 or 1% of the ground fished by

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October 2017

the sector. Annual effort expended within the survey area between 2000 and 2010 amounts to

approximately 18 000 hooks (0.01% of the total effort) and hake catch taken amounts to 1.2 tons (0.01% of

the total longline catch).

Long-line vessels vary from 18 m to 50 m in length and remain at sea for four to seven days at a time and

retain their catch on ice. A demersal long-line vessel may deploy either a double or single line which is

weighted along its length to keep it close to the seafloor (see Figure 4.25). Concrete blocks are placed at the

ends of each line to anchor it. These anchor positions are marked with an array of floats. If a double line

system is used, top and bottom lines are connected by means of dropper lines. Since the topline is more

buoyant than the bottom line, it is raised off the seafloor and minimises the risk of snagging or fouling.

The purpose of the topline is to aid in gear retrieval if the bottom line breaks at any point along the length of

the set line, which may be up to 30 km in length. Baited hooks are attached to the bottom line at regular

intervals by means of a snood. Gear is usually set at night at a speed of 5 to 9 knots. Once deployed the

line is left to soak for up to eight hours before retrieval. A line hauler is used to retrieve gear at a speed of

approximately 1 knot and usually takes six hours to complete. During hauling operations the vessel’s

manoeuvrability is severely restricted.

Angola

Angola does not target demersal finfish species using the long-lining technique.

Figure 4.23: Survey area in relation to demersal long-line catch (hake) off the coast of Namibia

(2000 – 2010).





October 2017

Figure 4.24: Average monthly catch landed by the Namibian demersal long-line fleet (2000 – 2010).

Figure 4.25: Typical configuration of demersal (bottom-set) hake long-line gear used in Namibian

waters.

4.4.1.8 Tuna pole

Namibia

Poling for tuna (predominantly albacore tuna, T. alalunga, and a very small amount of skipjack tuna, yellowfin

tuna and bigeye tuna), from mostly small boats (< 25 m), is common in southern Namibian waters. The

fishery is seasonal with vessel activity mostly from January to April and peak catches in February, March and

April (see Figure 4.26). Effort fluctuates according to the availability of fish in the area, but once a shoal of

tuna is located a number of vessels will move into the area and target a single shoal which may remain in the

area for days at a time. As such the fishery is dependent on window periods of favourable conditions relating

to catch availability.

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October 2017

Figure 4.26: Average monthly catch and effort recorded by the tuna pole and line fleet in Namibian

waters (2008 – 2013).

Although the ICCAT data available does not support detailed spatial analysis, it is known that aggregations

of albacore tuna occur in specific areas – in particular Tripp Seamount just north of the South Africa-Namibia

border. Catches in this area are, however, variable from year to year, although boats will frequent the area

knowing that albacore aggregate around Tripp Seamount after migrating through South African waters.

Movements of albacore between South Africa and Namibia is not clear although it is believed the fish move

northwards following bathymetric features and generally stay deeper than 200 m water depth. Within

Namibian waters, the fishery operates primarily southwards of 25°S between the 200 m and 500 m isobaths

and in particular over Tripp Seamount, well to the south of the proposed survey area. There has been no

recorded effort within the proposed survey area between 2009 and 2013 (Figure 4.27).

Whilst at sea, the majority of time is spent searching for fish with actual fishing events taking place over a

relatively short period of time. Sonars and echo sounders are used to locate schools of tuna. At the start of

fishing, water is sprayed outwards from high-pressure nozzles to simulate small baitfish aggregating near the

water surface, thereby attracting tuna to the surface. Live bait is flung out to entice the tuna to the surface

(chumming). Tuna swimming near the surface are caught with hand-held fishing poles. The ends of the 2 to

3 m poles are fitted with a short length of fishing line leading to a hook. Hooked fish are pulled from the

water and many tons can be landed in a short period of time. In order to land heavier fish, lines may be

strung from the ends of the poles to overhead blocks to increase lifting power (see Figure 4.28).

Angola

No impact is expected on the tuna pole fishery in Angola.

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October 2017

Figure 4.27: Survey area in relation to tuna pole and line-fish fishing effort (2009 – 2013).

Figure 4.28: Schematic diagram of pole and line operation (from www.fao.org/fishery





October 2017

4.4.1.9 Line-fish

Namibia

The traditional line fishery is based on only a few species that includes silver kob (Argyrosomus inodorus),

dusky kob (A. coronus), snoek (Thyrsites atun) and numerous shark species which are sold on the local

market or exported.

The two commercial components of the line-fish fishery comprise a fleet of between 10 and 13 ski-boats and

a fleet of 26 industrial vessels. While ski-boats fish close to the shore in the vicinity of Swakopmund and

Walvis Bay, the industrial vessels fish offshore areas between Walvis Bay and the northern border with

Angola. The fishery is limited in extent to around the ports and does not operate much further than 12 nm

(±22 km) offshore due to the operational range of vessels operating within this fishery. The distribution of

line-fish catch in relation to the proposed survey area is shown in Figure 4.29.

Angola

No impact is expected on the line-fish fishery in Angola.

Figure 4.29: Survey area in relation to the spatial range of ski-boats operating within the line-fish

sector along the Namibian coastline.





October 2017

4.4.1.10 Deep-sea crab

Namibia

The Namibian deep-sea crab fishery is based primarily on two species of crab, namely spider crab (Lithodes

ferox) and red crab (Chaceon maritae). The fishery commenced in 1973 with a peak catch of 10 000 t during

the 1983. Catches remained high (between 5 000 t and 7 000 t) during the 1980s. However, following this

heavy exploitation, catch rates dropped significantly to 2 000 t in 1997 and have been steadily increasing

since then. The fishery is currently small, with only four vessels currently operating from Walvis Bay. The

fishery is operational year-round and has a minimum operational depth limit of 400 m. The TAC for 2016

was set at 3 446 tons.

The distribution of red crab extends from approximately 5°S to just south of Walvis Bay at a depth range of

300 m and 1 000 m isobaths, with the highest concentrations occurring in the north-eastern extent of its

distribution. The fishing grounds extend between the 500 m and 900 m isobaths (see Figure 4.30). The

proposed survey area (excluding zones of acoustic disturbance) covers approximately 2 932 km2 or 14.7% of

the total ground fished by the sector. Annual effort expended within the survey area amounts to

approximately 14.2% of the total effort expended by the fishery and catch taken amounts to approximately

15% of the total landings.

The method of capture involves the setting of a demersal long-line with a string of approximately 400

Japanese-style pot traps attached to each line. Traps are made of plastic and dimensions are approximately

1.5 m width at the base and 0.7 m in height. They are spaced 15 m apart and typically baited with horse

mackerel or skipjack. The line is typically 6 000 m to 7 000 m in length and weighted at each end by a steel

anchor. A surface buoy and radar reflector mark each end of the line via a connecting dropper line that

allows retrieval of the gear. Up to 1 200 traps may be set each day (or two to three lines) and are left to soak

for between 24 and 120 hours before being retrieved.

Angola

The Angolan deep-sea red crab resource forms part of a single stock shared with Namibia, which is targeted

by the directed trap fishery.

4.4.1.11 Rock lobster

Namibia

The West Coast rock lobster (Jasus lalandii) is commercially exploited between 28º30'S and 25ºS from the

Orange River border in the south to Easter Cliffs/Sylvia Hill north of Mercury Island and generally to a depth

of 80 m. The catch season is a six-month period with a closed period extending from 1 May to 31 October

and highest activity levels experienced over January and February. The industry lands between 50% and

80% of the total TAC each season. The TAC for 2015/16 was set at 250 tons.

The fishery is spatially managed through the demarcation of catch grounds by management area, the closest

of which is situated approximately 820 km south of the proposed survey area. The number of active vessels

correlates to the allocated quota each season with 29 vessels active in 2010/11 and only 16 active during

2014/15.

Baited traps consisting of rectangular metal frames covered by netting are deployed from small dinghy’s and

delivered to larger catcher reefers to take to shore for processing. The rock lobster fishing fleet consists of

vessels that range in length from 7 m to 21 m. Traps are set at dusk and retrieved during the early morning

using a powerful winch for hauling.





October 2017

Angola

The fishery does not operate within Angolan waters.

Figure 4.30: Survey area in relation to the distribution of deep-sea red crab catch within Namibian

waters (2003 – 2011).

4.4.1.12 Fisheries research

The MFMR conducts regular research (biomass) surveys for demersal, mid-water and small pelagic species.

The method of abundance estimation from these surveys is based on depth stratification and trawls range in

depth from 100 m to 600 m. These surveys are normally fixed at specific times of the year and cover the

entire continental shelf from the Angolan to South African maritime border. Demersal trawl surveys normally

take place over a one month period between January and June. In some years the Benguela Current

Commission may conduct “transboundary” surveys. The duration of each trawl is between 30 minutes and

one hour. The survey stations covered during the 2015 survey are shown in Figure 4.31. The depth of

trawls undertaken within the proposed survey area ranged between 135 m and 600 m. An average of 216

trawls are carried out per survey, of which an average of 11 trawls (5.1%) are undertaken within the

proposed survey area.

Scientific acoustic surveys are carried out between June and March each year to estimate the biomass of

small pelagic species. These surveys cover the Namibian shelf from the coastline to the 500 m depth

contour (and up to the 2 000 m contour northwards of 18°30´S). The vessel surveys along pre-determined

transects that run perpendicular to depth contours (East-West / West-East direction). Acoustic research





October 2017

survey activity could be expected within the proposed seismic survey area to a maximum depth of 2 000 m.

Approximately 18 of a total of 66 survey transects undertaken in 2014 coincide with the proposed survey

area, which is equivalent to 27.3% of the total number of transects surveyed during a single survey.

Figure 4.31: Survey area in relation to the station layout covered during the 2015 hake swept-area

biomass survey (with depth contours of 100, 200 and 1 000 m).

4.4.2 SHIPPING TRANSPORT



the proposed survey area (see Figure 4.32). Fishing vessels would be encountered over the majority of the

survey area.

The two main ports in Namibia are (https://en.wikipedia.org/wiki/Namibian_Port_Authority):

• Port of Walvis Bay: Walvis Bay is Namibia's largest commercial port, handling on average 3 000

vessel calls per year and over 5.3 million tons of cargo. It offers direct access to principal shipping

routes and is a natural gateway for international trade. It has a sheltered deep water harbour which

benefits from a temperate climate; and

• Port of Lüderitz: Lüderitz Port is historically Namibia's second largest port, functioning mainly as a

fishing port; it has expanded in recent years to ship cargo from the mining industry and to support and

service offshore petroleum exploration and diamond mining activities.





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Figure 4.32: Major shipping routes around southern Africa. The southern boundary of the survey

area is also shown (purple outline). Data from the South African Data Centre for

Oceanography (image source: CSIR).

4.4.3 PROSPECTING AND MINING

4.4.3.1 Oil and gas prospecting and production

Namibian Licence Blocks in relation to the proposed survey area are shown in Figure 1.1.

Exploration for petroleum and natural gas in Namibia has taken place in the Ovambo and Nama basins and

on the continental shelf. To date, approximately 15 wells have been drilled in the Namibian offshore

(including seven in the Kudu Gas Field). The only substantial hydrocarbon occurrence discovered so far is

the Kudu gas field. The Kudu Gas Field has proven to be a significant gas reserve with proven reserves of

at least 1.4 trillion cubic feet of gas and an upside of 20 trillion cubic feet (http://www.mme.gov.na

/gsn/fossilfuels.htm).

4.4.3.2 Diamond prospecting and mining

The proposed survey area overlaps with a number of offshore Exclusive Prospecting Licences (EPLs) and

Mining Licences (see Figure 4.33). However, current activities in the EPLs are minimal to non-existent with

the only active operations being diamond mining south of Lüderitz.

Walvis Bay

Lüderitz





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Figure 4.33: Project - environment interaction points in central and southern Namibia, illustrating

the distribution of existing industries and other users in the coastal region. The

approximate locality of the survey area is also shown.

4.4.3.3 Prospecting and mining of other minerals

Phosphate

In July 2008 Bonaparte Diamond Mines NL commenced with seabed sampling (core and grab samples)

within its 1 000 km2 licence area, directly west of Meob Bay and south of Walvis Bay. Applications have

been made for a further nine exclusive exploration licences, covering an additional 9 000 km2, in areas of

phosphate enrichment.

Namibian Marine Phosphate (Pty) Ltd was awarded a 20-year mining licence for the Sandpiper Marine

Phosphate Project, which is located approximately 120 km to the south of Walvis Bay and approximately

60 km off the coast. The licence area is approximately 7 000 km2 in extent located in water depths ranging





October 2017

from 180 m to 300 m. MET has subsequently set aside the award of the Environmental Clearance

Certificate (ref. Official Media Statement No. 6, November 2016, http://www.namphos.com/videos/media-

releases/item/182-nmp-media-statement-2016-november.html, Accessed 6 Feb 20-17).

Manganese nodules in ultra-deep water

Rogers (1987, 1995) and Rogers and Bremner (1991) report that manganese nodules enriched in valuable

metals occur in deep water areas (>4 000 m) on the West Coast of Southern Africa, offshore of the survey

area. The nickel, copper and cobalt contents of the nodules fall below the current mining economic cut-off

grade of 2% over most of the area, but the possibility exists for mineral grade nodules in the areas north of

33ºS in the Cape Basin and off northern Namaqualand.

4.4.4 RECREATIONAL UTILISATION

Recreational use of the northern Namibian coastline and inshore areas is negligible and restricted primarily

to the area around Henties Bay, Swakopmund, Walvis Bay and Lüderitz, all of which lie well south of the

proposed survey area. Recreational activities offshore of the Namib-Naukluft and the Skeleton Coast

National Park are similarly limited.

4.4.5 OTHER HUMAN UTILISATION

4.4.5.1 Undersea cables

There are a number of submarine telecommunications cable systems across the Atlantic and the Indian

Ocean (see Figure 4.34), including:

• South Atlantic Telecommunications cable No.3 / West African Submarine Cable / South Africa Far

East (SAT3/WASC/SAFE): This cable system is divided into two sub-systems, SAT3/WASC in the

Atlantic Ocean and SAFE in the Indian Ocean. The SAT3/WASC sub-system connects Portugal

(Sesimbra) with South Africa (Melkbosstrand). From Melkbosstrand the SAT-3/WASC sub-system is

extended via the SAFE sub-system to Malaysia (Penang) and has intermediate landing points at

Mtunzini South Africa, Saint Paul Reunion, Bale Jacot Mauritius and Cochin India (www.safe-

sat3.co.za).

• Eastern Africa Submarine Cable System (EASSy): This is a high bandwidth fibre optic cable system,

which connects countries of eastern Africa to the rest of the world. EASSy runs from Mtunzini (off the

East Coast) in South Africa to Port Sudan in Sudan, with landing points in nine countries, and

connected to at least ten landlocked countries.

• West Africa Cable System (WACS): WACS is 14 530 km in length, linking South Africa (Yzerfontein)

and the United Kingdom (London). It has 14 landing points, 12 along the western coast of Africa

(including Swakopmund) and two in Europe (Portugal and England) completed on land by a cable

termination station in London.

• African Coast to Europe (ACE): The ACE submarine communications cable is a 17 000 km cable

system along the West Coast of Africa between France and South Africa (Yzerfontein). The ACE

system has a landing point in Swakopmund.

In summary, Namibia is connected to the ACE and the WACS submarine cables, as well as the SAFE

submarine cable through South Africa. There is an exclusion zone applicable to the telecommunication

cables 1 nm (approximately 1.9 km) each side of the cable in which no anchoring is permitted.





October 2017

Figure 4.34: Configuration of the current African undersea cable systems, November 2014

(From http://www.manypossibilities.net).

4.4.5.2 Archaeological sites

Over a thousand shipwrecked vessels line the Skeleton Coast in Namibia, many of which are related to

dense fog and rough seas. The majority of known wrecks along this coast are located in relatively shallow

water close inshore. In Namibian waters, wrecks older than 50 years are declared national monuments.

Wrecks would not be affected by the proposed seismic survey programme.

4.4.5.3 Mariculture

Namibia has a developing mariculture industry for oysters (Crassostrea gigas and Ostrea edulis), black

mussel (Choromytilus meridionalis and MytilusGallo-provincialis), abalone (Haliotis midae) and seaweed

(Gracilaria gracilis) (Oellermann, 2007). Mariculture methods vary but include rafts, suspended long-lines,

racks in ponds and onshore flow-through tanks. As the mariculture activities take place in sheltered bays

e.g. Lüderitz and Walvis Bay they are highly sensitive to water quality variability associated with

hydrocarbons, sulphide eruptions, plankton blooms (water anoxia included) and many other factors such as

heavy metals. Current production is variable but approximates 1 000 tons of shellfish per annum and is

concentrated in Walvis Bay and Lüderitz Bay. A recent development is the provision of water area for

“ranching”, which is the seeding of wild stocks of abalone in restricted areas.

These various mariculture activities would not be affected in any way by the proposed seismic activities

programme.





October 2017

4.4.5.4 Guano harvesting

There is limited guano harvesting on guano platforms off the coast of Namibia. There is a 1.7 ha wooden

platform, approximately 200 m offshore, between Swakopmund and Walvis Bay (see Figure 4.35). North of

Swakopmund at the Salt Pans and at Cape Cross, a further two platforms (4 ha each) have been erected

(ref. http://www.namibweb.com/guano.htm, 6 Feb 23017).

Figure 4.35: Guano platform off the coast of Namibia between Swakopmund and Walvis Bay (ref.

https://freeassociationdesign.wordpress.com/2010/09/10/islands-and-post-peak-

guano/, 6 Feb 2017).

4.4.5.5 Conservation areas and Marine Protected Areas

Numerous conservation areas and a MPA exist along the Namibian coastline, although these are all located

inshore and to the south of the proposed survey area. However, for the sake of completeness, they are

briefly summarised below.

The Skeleton Coast National Park (see Figure 4.10) extends 500 km from the Ugab River in the south to the

Kunene River in the north, covering a total land-area of approximately 16 400 km2. The coastline is

characterised by many shipwrecks, dense coastal fogs and cold onshore winds. The general public has

access only to the southern section between the Ugab and Hoanib rivers, staying at Terrace Bay and Torra

Bay. Although open all year to linefish boats, Torra Bay and Terrace Bay are partly closed or restricted to

rock- and surf-anglers. There is a seal colony at Cape Frio. The northern section of the Skeleton Coast

Park is a tourism concession area and restricted to fly-in safaris only. The park is managed as a wilderness

area by MET due to its ecological sensitivity.

The Dorob National Park, formerly the National West Coast Tourist Recreation Area, was gazetted as a

national park under the Nature Conservation Ordinance No. 4 of 1975 in December 2010. The park extends

along 1 600 kms of coastline between the Kuiseb Delta and the Ugab River, and together with Namib-

Naukluft Park covers an area of 107 540 km2. While tourism, sports and recreational activities are allowed in

non-sensitive areas, the remainder of the park has been divided into zones, which include Damara tern

breeding sites, gravel plains, important birds areas, the Kuiseb Delta, Sandwich Harbour, Swakop River,

Tsumas Delta, Walvis Bay Lagoon, birding areas and lichen fields.





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The Cape Cross Seal Reserve, which is located within the Dorob National Park, is situated approximately

130 km north of Swakopmund. With a surrounding area of 60 km2, the Cape Cross Seal Reserve was

proclaimed in 1968 to protect the largest of the 23 breeding colonies of Cape Fur seals along the southern

African West Coast. Emergent offshore reefs, which serve as seabird nesting areas, are also protected.

Sandwich Harbour, located 55 km south of Walvis Bay, is one of Namibia’s four proclaimed Ramsar sites

and one of southern Africa’s richest coastal wetlands. The area consists of two distinct parts: a northern,

saltmarsh and adjoining intertidal sand flat area, which supports typical emergent vegetation, and a southern

area of mudflats and raised shingle bars under tidal influence. The area supports an extremely rich avifauna

including eight endangered species among the large numbers of waders, terns, pelicans and flamingos.

Several archaeological sites dating back 1 000 years also exist within the area (Barnard, 1998).

Walvis Bay lagoon is the largest single area of shallow sheltered water along the Namibian coastline.

The tidal inlet consists of adjacent intertidal areas, Pelican Point, mudflats exposed at low tide, and sandbars

serving as roosting and feeding sites for resident and migratory birds. The wetland consists of natural areas

of the lagoon and the Walvis Bay saltworks (Barnard, 1998). The site supports up to 250 000 individuals of

wetland birds, some species such as flamingos occurring in impressive numbers. Eleven endangered bird

species are regularly observed (http://www.ramsar.org/ profile/profiles_namibia. htm).

Conservation areas in southern Namibia include the Sperrgebiet, which was proclaimed in 1908 and covers

an area of approximately 30 000 km2 between latitude 26° in the north and the Orange River in the south,

extending inland from the coast for 100 km. The Sperrgebiet was proclaimed to prevent public access to the

rich surface diamond deposits occurring in the area, and has largely remained closed off to general public

access since then. However, as diamond mining has actually remained confined to the narrow coastal strip

and along the banks of the Orange River, most the area has effectively been preserved as a pristine

wilderness. Although large parts of the Sperrgebiet have since been de-proclaimed from exclusive

prospecting and mining licences previously owned by Namdeb, and have now reverted to unproclaimed

State land, most of the area is not yet formally managed as a conservation area. The north-eastern portion

of the area (approximately 4 000 km2) now forms part of the Namib-Naukluft Park.

The Lüderitz Bay and Ichaboe Island Rock-Lobster Sanctuaries were proclaimed by South Africa in 1939

and 1951, respectively (Matthews & Smit, 1979), and subsequently maintained as reserves by the Ministry of

Fisheries and Marine Resources after Namibian independence. There is no restriction on other activities

within these reserves.

The Orange River Mouth wetland provides an important habitat for large numbers of a great diversity of

wetland birds. The area was designated a Ramsar site in June 1991, and processes are underway to

declare a jointly-managed transboundary Ramsar reserve.

The first Namibian MPA was proposed in 2007 with the purpose of protecting sensitive ecosystems and

breeding and foraging areas for seabirds and marine mammals, as well as protecting important spawning

and nursery grounds for fish and other marine resources (such as rock lobster). The proposed MPA

comprises a coastal strip extending from Hollamsbird Island (24º38’S) in the north to Chamais Bay (27º57’S)

in the south, spanning approximately three degrees of latitude and an average width of 30 km, including 16

specified offshore islands, islets and rocks (Currie et al. 2008). The Namibian Islands’ MPA was officially

launched on 2 July 2009 under the Namibian Marine Resources Act (No. 29 of 1992 and No. 27 of 2000).

The MPA spans an area of 9 555 km2, and includes a rock-lobster sanctuary constituting 478 km

2 between

Chameis Bay and Prince of Wales Bay. The offshore islands, whose combined surface area amounts to

only 2.35 km2 have been given priority conservation and highest protection status (Currie et al., 2009).




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5 ENVIRONMENTAL IMPACT ASSESSMENT

This chapter describes and assesses the significance of potential impacts associated with the proposed

seismic survey off northern Namibia. The assessment is based, to a large extent, on a generic description of

3D seismic surveys and the specialist studies undertaken as part of the EIA process.

5.1 INTRODUCTION

The potential impacts of the proposed activities are addressed in three categories, namely:

1. Seismic and support vessels (including helicopter) operation;

2. Impacts of seismic noise on marine fauna; and

3. Impacts of seismic activities on other users of the sea.

All impacts are systematically assessed and presented according to predefined rating scales

(see Appendix 1). For each potential impact a table is provided that summarises the significance level

assessment for that impact. Mitigation or optimisation measures are proposed which could ameliorate the

negative impacts or enhance potential benefits, respectively. The status of all impacts should be considered

to be negative unless otherwise indicated. The significance of impacts with and without mitigation is also

assessed.

Unless otherwise indicated, all potential impacts discussed below would only occur for the duration of the

survey, i.e. nine to ten months. Although the survey area extends across a large area of the northern

Namibian offshore, the majority of the impacts would be localised at any one time, due to the transient nature

of survey activities.

5.2 IMPACT OF NORMAL SEISMIC / SUPPORT VESSELS AND HELICOPTER OPERATION

5.2.1 EMISSIONS TO THE ATMOSPHERE

Description of impact

Emissions to the atmosphere during a seismic survey may include exhaust gases from the use of diesel as

fuel for generators and motors, and the burning of wastes. Combustion of fuel in aircraft engines would also

results in emissions of CO2 and NOx, as well as water vapour and particulates.

Diesel exhaust gas comprises mainly carbon dioxide (CO2) as well as several toxic gases such as nitrogen

oxides (NOX), sulphur oxides (SOX) and carbon monoxide (CO). In addition, diesel combustion can produce

hydrocarbons (Total Hydrocarbons and Volatile Organic Compounds). Smoke and particulate matter (soot)

are also produced during diesel combustion.

Incineration of waste on-board would also release soot as well as CO, CO2 and dioxins (depending on the

composition of waste). However, many vessels do not have an incinerator on-board. In these

circumstances solid waste would be stored separately on-board for later onshore disposal.

Assessment

The atmospheric emissions from the seismic and support vessels are expected to be similar to those from

similar diesel-powered vessel of comparable tonnages (approximately 11 000 tonnes), with the addition of

the emissions from the airgun compressors. The volumes of solid waste incinerated on-board, and hence

also the volumes of atmospheric emissions, would be minimal and incineration would comply with the

relevant MARPOL 73/78 standards.




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It is not expected that such emissions would have a direct effect on any other activity. The potential impact

of emissions to the atmosphere during seismic survey operations would be limited to the survey area

(but localised at any one time), of low intensity and is considered to be of VERY LOW significance with or

without the implementation of mitigation measures (see Table 5.1).

Mitigation

No mitigation is deemed necessary, but it is recommended that all diesel motors and generators receive

adequate maintenance to minimise soot and un-burnt diesel released to the atmosphere.

Table 5.1: Impact of atmospheric emissions from the seismic and support vessels, and

helicopter.

Extent Duration Intensity Probability Significance Confidence

Without mitigation Local Short-term Low Definite Very Low High

With mitigation Local Short-term Low Definite VERY LOW High

5.2.2 DISCHARGES/DISPOSAL TO THE SEA

Discharges from the seismic and support vessels to the marine environment include deck drainage,

machinery space drainage, sewage, galley wastes, solid wastes and accidental hydrocarbon spills.

5.2.2.1 Deck drainage


Drainage of deck areas from precipitation, sea spray or routine operations (e.g. deck and equipment cleaning

and fire drills) may result in small volumes of oils, solvents or cleaners being introduced into the marine

environment.

Assessment

The discharge into the sea of any oil or oily mixture that may originate from the seismic and support vessels

is prohibited in terms of Regulation 21 of MARPOL (Annex I) except when the oil content of the discharge

without dilution does not exceed 15 ppm. To ensure MARPOL compliance all deck drainage from work

spaces should be collected and piped into an on-board sump tank for treatment prior to discharge. Oily

waste substances would be shipped to land for treatment and disposal. If no such equipment is available

oily water would be retained on-board and disposed of at an appropriate facility at port.

Based on the small volumes, high energy sea conditions, distance from the coast (27 km at closest point)

and non-continuous nature of the discharge, the potential impact of deck drainage on the marine

environment would be localised, of low intensity over the short-term, and is considered to be of VERY LOW

significance with or without mitigation (see Table 5.2).

Mitigation

The following measures are recommended for mitigation of deck drainage discharges from the seismic and

support vessels:

• Deck drainage should be routed to a separate drainage system (oily water catchment system) for

treatment to ensure compliance with MARPOL (15 ppm);

• All process areas should be bunded to ensure drainage water flows into the closed drainage system;




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• Drip trays should be used to collect run-off from equipment that is not contained within a bunded area

and the contents routed to the closed drainage system;

• Low-toxicity biodegradable detergents should be used in cleaning of all deck spillage;

• All hydraulic systems should be adequately maintained and hydraulic hoses should be frequently

inspected; and

• Spill management training and awareness should be provided to crew members of the need for

thorough cleaning-up of any spillages immediately after they occur in order to minimise the volume of

contaminants washing off decks.

Table 5.2: Impact of deck drainage from the seismic and support vessels.


Without mitigation Local Short-term Low Highly

Probable Very Low High

With mitigation Local Short-term Low Highly

Probable VERY LOW High

5.2.2.2 Machinery space drainage


Small volumes of oil such as diesel fuel, lubricants, grease, etc. used within the machinery space of a

seismic and support vessel could enter the marine environment.

Assessment

All operations would comply fully with international agreed standards regulated under MARPOL 73/78.

All machinery space drainage would pass through an oil/water filter to reduce the oil in water concentration to

less than 15 ppm, in accordance with Regulation 21 of MARPOL (Annex I). If no such equipment is available

oily water would be retained on-board and disposed of at an appropriate facility at port.

Concentrations of oil reaching the marine environment through drainage of machinery spaces are, therefore,

expected to be low. Based on the small volumes, high energy sea conditions, distance from the coast

(27 km at closest point) and non-continuous nature of the discharge, the potential impact of such low

concentrations would be of low intensity and limited to the survey area (but localised at any one time) over

the short-term. The potential impact of machinery space drainage on the marine environment is therefore

considered to be of VERY LOW significance with or without mitigation (see Table 5.3).

Mitigation

Mitigation is as for deck drainage (see Section 5.2.2.1).

Table 5.3: Impact of machinery space drainage from the seismic and support vessels.









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5.2.2.3 Sewage


Sewage poses an organic and bacterial loading on the natural degradation processes of the sea, resulting in

an increased biological oxygen demand (BOD). This could result in anaerobic conditions in the marine

environment. Although treated sewage would also increase BOD, it does not pose a bacterial load.

Assessment

The proposed seismic survey is expected to take in the order of nine to ten months, depending on, amongst

other things, weather conditions. The volumes of sewage wastes released from the seismic and support

vessels would be small and comparable to volumes produced by vessels of similar crew compliment

(up to 50 people).

All sewage would be treated to the required MARPOL 73/78 standard prior to release into the marine

environment, where the high wind and wave energy is expected to result in rapid dispersal. Discharges of

sewage, according to MARPOL 73/78 standards, would be comminuted and disinfected prior to disposal to

the marine environment if between 4 nm (± 7.5 km) and 12 nm (± 22 km) from the coast, and no disposal

would occur within 4 nm of the coast. Disposal beyond 12 nm requires no treatment. Sewage would not be

discharged instantaneously but at a moderate rate when the vessel is en route and travelling at no less than

4 knots.


and non-continuous nature of the discharge, the potential impact of sewage effluent from the seismic and

support vessels on the marine environment is expected to be limited to the survey area (but localised at any

one time) over the short-term, and is therefore considered to be of VERY LOW significance with or without

mitigation (see Table 5.4).

Mitigation

Ensure compliance with the MARPOL 73/78 standards.

Table 5.4: Impact of sewage effluent discharge from the seismic and support vessels.






5.2.2.4 Galley waste


Galley wastes, comprising mostly of biodegradable food waste, would place a small organic and bacterial

loading on the marine environment.

Assessment

The volume of galley waste from a seismic and support vessel would be small and comparable to wastes

from any vessel of a similar crew compliment (up to 50 people). Discharges of galley wastes, according to

MARPOL 73/78 standards, would be comminuted to particle sizes smaller than 25 mm prior to disposal to

the marine environment if less than 12 nm (± 22 km) from the coast and with no disposal within 3 nm

(± 5.5 km) of the coast.




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and non-continuous nature of the discharge, the potential impact of galley waste disposal on the marine

environment would be of low intensity and limited to the survey area (but localised at any one time) over the

short-term. The potential impact of galley waste on the marine environment is therefore considered to be of

VERY LOW significance with or without mitigation (see Table 5.5).

Mitigation

Ensure compliance with the MARPOL 73/78 standards.

Table 5.5: Impact of galley waste disposal from the seismic and support vessels.






5.2.2.5 Solid waste


The disposal of solid waste comprising non-biodegradable domestic waste, packaging and operational

industrial waste into the sea could pose a hazard to marine fauna, may contain contaminant chemicals and

could end up as visual pollution at sea, on the seashore or on the seabed.

Assessment

Solid waste would either be incinerated on-board or transported ashore for disposal on land, and

consequently would have no impact on the marine environment. However, a spill may result in a small

amount of waste entering the marine environment (e.g. blown by wind, spill during transfer to support vessel,

etc.). Hazardous waste would be disposed of by specialist waste disposal contractors.

The potential impact of the disposal of solid waste on the marine environment is therefore INSIGNIFICANT

(see Table 5.6).

Mitigation

The following measures are recommended for the mitigation of waste:


• On-board solid waste storage is to be secure; and

• The disposal of waste (solid and hazardous) onshore must be in accordance with the appropriate laws

and ordinances.

Table 5.6: Impact of solid waste disposal from the seismic and support vessels.


Without mitigation Local Short-term Zero Improbable Insignificant Medium

With mitigation Local Short-term Zero Improbable INSIGNIFICANT Medium




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5.2.2.6 Accidental oil spill during bunkering / refuelling


Accidental hydrocarbon spills of varying sizes could result from related operations, for example the bunkering

of fuel oil at sea. This scenario assumes that an accidental spillage of oil would occur.

Assessment

Spillages and leakages during bunkering operations are a primary source of oil pollution from ships. Many of

the spillages that occur can be attributed to human error. Thus all bunkering operations should be carefully

planned and executed in accordance with MARPOL 73/78 standards. Spillages and leakages during

bunkering operations are generally relatively small (< 1 000 litres). Bunkering operations are expected to

take place within the Port of Walvis Bay or at sea during the survey and would depend on the contractor’s

project plan and fuel availability.

Bunkering within the port limits would be less likely to be affected by environmental factors (e.g. sea state

and wind) and any accidental spills would be easier to contain and remediate. Any spill within the port limits

would be managed in accordance with the port’s local oil spill contingency plan. The impact associated with

an oil spill within the port limits is considered to be INSIGNIFICANT.

Accidental spillages from offshore bunkering operations would be more difficult to contain. However, since

the closest survey line to the shore would be located further than 27 km offshore, a small spill would more

than likely disappear before reaching the shore due to evaporative processes and the high energy marine

environment off the Namibian coast. In addition, the dominant winds originate from the south and thus do

not blow directly towards the coast. Any spills would be managed in accordance with procedures specified in

the project specific Emergency Response Plan and Shipboard Oil Pollution Emergency Plan. Since a small

spill would most likely never reach the coast, the potential impact on the biophysical environment is expected

to be localised, of medium to high intensity over the short-term, and is therefore considered to be of LOW

significance without mitigation and VERY LOW with mitigation (see Table 5.7).

Mitigation

• Spectrum and the appointed seismic contractor must prepare a project specific Emergency Response

Plan and Shipboard Oil Pollution Emergency Plan for the proposed seismic survey programme, which

defines their organisational structure and protocols that would be implemented to respond to any

incident (including accidental oil / fuel spills) in a safe, rapid, effective and efficient manner. These

plans should be submitted to MME for information purposes as part of their formal notification prior to

survey commencement;


















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• Crew must be trained in spill management; and


NAMPORT and the Commissioner for Petroleum Affairs.

Table 5.7: Impact of an accidental oil spill during bunkering operations.


Bunkering within port

Without mitigation Local Short-term Very Low Improbable Insignificant Medium

With mitigation Local Short-term Very Low Improbable INSIGNIFICANT Medium

Offshore bunkering

Without mitigation Local Short-term Medium

to High Improbable LOW Medium

With mitigation Local Short-term Medium Improbable VERY LOW Medium

5.2.3 NOISE FROM VESSEL AND HELICOPTER OPERATIONS

5.2.3.1 Noise from seismic and support vessel operations

Impact description

The noise from seismic and support vessels could result in localised disturbance of marine fauna.

Impact assessment

Noise from seismic and support vessels is likely to be no higher than that from other small shipping vessels

in the region. The potential impact of noise from seismic and support vessel operations on marine fauna is

expected to be limited to the survey area (but localised at any one time) and of low intensity in the short-

term. The significance of this impact is therefore assessed to be VERY LOW with and without mitigation

(Table 5.8).

Mitigation measures

No measures are deemed necessary to mitigate noise impacts from seismic and support vessel operations.

Table 5.8: Impact of noise from seismic and support vessel operations.


Without mitigation Local Short-term Low Probable Very Low Medium

With mitigation No mitigation is considered necessary

5.2.3.2 Noise from helicopter operations

Impact description

Helicopters could, although highly unlikely, be used for crew or supply transfers between the seismic and

support vessels and the mainland (Walvis Bay), which could result in localised disturbance of fauna.

Helicopters may also be used in cases of emergency (e.g. medivac).




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Impact assessment

Although reported behavioural reactions by seabirds, turtles and whales to aircrafts are highly variable and

often anecdotal, it is safe to assume that any observed effects as a result of helicopter support would be in

response to both acoustic and visual cues.

Low altitude flights (especially near the coast) can have a significant disturbance impact on cetaceans during

their breeding and mating season. The level of disturbance would depend on the distance and altitude of the

aircraft from the animals (particularly the angle of incidence to the water surface) and the prevailing sea

conditions.

Similarly, low altitude flights over bird breeding colonies could result in temporary abandonment of nests and

exposure of eggs and chicks leading to increased predation risk. In general most breed on islands or on the

man-made guano platforms in Walvis Bay, Swakopmund and Cape Cross. The islands along the Namibian

coast therefore provide a vital breeding habitat to most species of seabirds that breed in Namibia. The

nearest nesting grounds for gannets and African Penguins are at Ichaboe Island, Halifax and Possession

Islands, which are over 500 km to the south of the proposed survey area. The Kunene River mouth and its

estuary at the border with Angola also serves as an extremely important wetland for coastal birds,

particularly the near threatened Damara Tern. Flight paths should thus avoid these breeding areas.

Seals may also experience severe disturbance from low-flying aircraft usually reacting by showing a startle

response and moving rapidly into the water. Although any observed response is usually short-lived,

disturbance of breeding seals can lead to pup mortalities through abandonment or injury by fleeing,

frightened adults. Flight paths should thus avoid the seal colonies between Walvis Bay and the survey area,

including Cape Cross, Möwe Bay and Cape Frio (see Figure 4.10).

Although such impacts would be local in the area of a colony, they may have wider ramifications over the

range of affected species and are deemed to range from low to high intensity. The significance of impact is

considered to range from low to medium significance (see Table 5.9), if helicopter flight paths cross any of

these areas at an altitude of less than 2 000 ft or 600 m. Since the use of helicopters for crew changes is

considered highly unlikely, this impact is considered to be improbable.

Mitigation measures




• Extensive coastal flights (parallel to the coast within 1 nm of the shore) should be avoided; and


If the suggested mitigation measures are implemented, this impact is expected to be VERY LOW

(see Table 5.9).

Table 5.9: Impact of noise from helicopter operations.


Without mitigation Local Short-term Low to High Improbable Low to

Medium Medium

With mitigation Local Short-term Low Improbable VERY LOW Medium




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5.3 IMPACT OF SEISMIC NOISE ON MARINE FAUNA

5.3.1 POTENTIAL IMPACTS ON PLANKTON SPECIES

Plankton, which are species that are unable to determine their direction of travel within the water column,

comprise bacterioplankton (bacterial component of plankton), phytoplankton (floral plankton) and

zooplankton (faunal plankton). Zooplankton includes ichthyoplankton (planktonic larval stages of fish and

invertebrates and eggs), as well as holoplankton (species that spend their entire life-cycle as plankton).


Potential impacts of seismic pulses on plankton could include physiological injury and/or mortality.

No behavioural avoidance of the seismic survey area by plankton or invertebrates would occur. Limited

indirect impacts may arise from effects on predators or prey.

Assessment

Review of the literature suggests that mortality or injury to plankton would occur in the immediate vicinity of

the airgun sound source within metres of the firing airgun sound sources. Impacts would thus be of high

intensity at very close range (< 5 m from the airguns), but this would be no more significant than the effect of

the wash from ships propellers and bow waves.


characteristic of the area. The spatial and temporal variation in upwelling results in considerable variability in

phytoplankton biomass in both longshore and offshore directions. As the majority of zooplankton are primary

consumers, zooplankton biomass is strongly correlated to that of phytoplankton (i.e. low biomass

immediately following upwelling, with increases tracking the development of phytoplankton blooms). Since

the proposed survey area is located offshore of an upwelling cell (see Figure 4.6), it is expected that

phytoplankton and zooplankton abundances will be seasonally variable. The preferred spawning grounds of

numerous commercially exploited fish species are located off central and northern Namibia, which is very

important to commercial fisheries. The proposed seismic survey area overlaps with the summer to autumn

spawning area for anchovy, pilchard and horse mackerel, but lies offshore of cob and steenbras spawning

areas (see Figure 4.8). Therefore, ichthyoplankton abundances in the survey area are expected to be

seasonally high.

Considering the spatial extent of these spawning areas, and as plankton distribution is naturally temporally

and spatially variable and natural mortality rates are high (with 36% of the phytoplankton and 5% of the

zooplankton estimated to be lost to the seabed annually), any impacts are considered to be of low to

negligible intensity across the immediate survey area (i.e. localised) and for the duration of the survey (short-

term). The potential impact of seismic noise on plankton is consequently deemed to be of VERY LOW

significance both with and without mitigation (see Table 5.10).

Mitigation

No measures to mitigate the impacts of seismic sounds on plankton are deemed necessary or practical.

Table 5.10: Impact of seismic noise on plankton.







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5.3.2 POTENTIAL IMPACTS TO MARINE INVERTEBRATES


Most marine invertebrates do not possess hearing organs that perceive sound pressure, although many

have mechanoreceptors or statocyst organs that are sensitive to hydroacoustic disturbances. Potential

impacts of seismic pulses on invertebrates could include physiological injury and behavioural avoidance of

seismic survey areas. Masking of environmental sounds and indirect impacts due to effects on predators or

prey have not been documented and are highly unlikely.

Assessment

Physiological injury and mortality

Although there is little published information on the effects of seismic surveys on invertebrate fauna, lethal

and sub-lethal effects have been observed under experimental conditions. It has been postulated that

shellfish, crustaceans and most other invertebrates can only hear seismic survey sounds at very close range

(< 15 m away). This implies that only surveys conducted in very shallow water would have any detrimental

effects. As the proposed survey would mostly be conducted in excess of approximately 150 m water depth,

the received noise at the seabed would be within the far-field range and outside of distances at which

physiological injury of benthic invertebrates would be expected. The potential impact of seismic noise on

physiological injury or mortality of invertebrates is consequently deemed of low to negligible intensity across

the immediate survey area (i.e. localised) and for the survey duration and is considered to be of VERY LOW

significance both with and without mitigation (see Table 5.11).

Seismic surveying could also have an impact on pelagic cephalopods (e.g. the colossal or giant squid),

which could potentially occur in the project area. Although a causative link to seismic surveys has not been

established with certainty, giant squid strandings (all with severe internal injuries from ascending from depth

too quickly) coincident with seismic surveys have been reported. Although the potential impact on pelagic

cephalopods could potentially be of high intensity, the probability of encountering pelagic cephalopods is

considered low. Thus the impact is also deemed to be of VERY LOW significance both without and with

mitigation.

Behavioural avoidance of seismic survey area

Similarly, there is little published information on the effects of seismic surveys on the response of

invertebrate fauna to seismic impulses. Limited avoidance of airgun sounds may occur in mobile neritic and

pelagic invertebrates and is deemed to be of low intensity. Of the marine invertebrates only cephalopods are

receptive to the far-field sounds of seismic airgun arrays. Although consistent avoidance has not been

reported, behavioural changes have been observed at 2 to 5 km from an approaching large seismic source.

The received noise at the seabed would be within the far-field range and outside of distances at which

avoidance of benthic invertebrates would be expected, but potentially within the response range of

cephalopods. The potential impact of seismic noise on invertebrate behaviour is consequently deemed of

low to negligible intensity across the immediate survey area and for the survey duration and is considered to

be of VERY LOW significance both with and without mitigation (see Table 5.11).

Mitigation

No mitigation measures for potential impacts on marine invertebrates are feasible or deemed necessary.




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October 2017

Table 5.11: Impact of seismic noise on marine invertebrates


Physiological injury

Without mitigation Local Short-term Low to high Probable Very Low Medium


Behavioural avoidance



5.3.3 POTENTIAL IMPACTS ON FISH

The potential impact of seismic noise on fish larvae is discussed under Section 5.3.1 above and this section

discusses the impact on adult fish only.


A review of the available literature suggests that potential impacts of seismic pulses to fish species

(including sharks) could include physiological injury and mortality, behavioural avoidance of the seismic

survey area, masking of environmental sounds and communication, disturbance to spawning and recruitment

and indirect impacts due to effects on predators or prey.

Assessment


The greatest risk of pathological injury from seismic sound sources is for species that establish home ranges

on shallow-water reefs or congregate in inshore waters to spawn or feed, and those displaying an instinctive

alarm response to hide on the seabed or in the reef rather than flee. Large demersal or reef-fish species

with swim-bladders are also more susceptible than those without this organ. Such species may suffer

pathological injury or severe hearing damage and adverse effects may intensify and last for a considerable

time after the termination of the sound source. However, as the proposed survey area is mostly located in

water depths of beyond 150 m, the received noise by demersal species at the seabed would be within the

far-field range, and outside of distances at which physiological injury or avoidance would be expected.

The most likely fish species to be encountered in the proposed survey area would be the large pelagic

species, such as the highly migratory tuna and billfish, which occur offshore of the 100 m isobaths. These

large pelagic species are known to aggregate around bathymetric features such as the Walvis Ridge to feed,

and as such are expected to occur year-round in the proposed survey area, with commercial catches

peaking between March and May. As the 10-month seismic survey is scheduled to commence in the fourth

quarter of 2017, the likelihood of encountering tuna and billfish is high. However, given the high mobility of

most large pelagic species, it is assumed that the majority of fish species would avoid seismic noise at levels

below those where physiological injury or mortality would result. Furthermore, in many of the large pelagic

species the swim-bladders are either underdeveloped or absent, and the risk of physiological injury through

damage of this organ is therefore lower. Possible injury or mortality in pelagic species could occur on

initiation of a sound source at full pressure in the immediate vicinity of fish, or where reproductive or feeding

behaviour override a flight response to seismic survey sounds. The potential physiological impact on pelagic

species would be of high intensity. The potential physiological impact on demersal species would, however,

be insignificant as they would only be affected in the far-field range, if at all. The duration of the impact on

the population would be limited to the short-term. The impact is, therefore, considered to be of low

significance without the implementation of mitigation and of VERY LOW significance with mitigation

measures.




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Behavioural responses are varied and include avoidance of seismic survey areas, changes in depth

distribution and schooling behaviour, startle response and changes in feeding behaviours of some fish.

Behavioural responses such as avoidance of the seismic survey area and changes in feeding behaviours

of some fish to seismic sounds have been documented at received levels of about 160 dB re 1 µPa.

Behavioural effects are generally short-term with duration of the effect being less than or equal to the

duration of exposure, although these vary between species and individuals, and are dependent on the

properties of the received sound. However, concerns have recently been raised by the tuna fishing industry

that seismic survey activities in southern Namibia are linked to reductions in tuna catches. However,

according to other sources, it is probable that fluctuating tuna catches are caused by a number of variables

(e.g. fluctuation of fishing effort, general decline in longfin tuna abundance and changes in fishing strategy)

(Attwood, 2014). This is supported by the briefing paper prepared by Dr Gabi Schneider of the GSN

(Schneider & Muyongo, 2013), which states that a simple correlation between seismic survey acquisition in

Namibian waters and reduced tuna catches cannot be inferred and more in-depth research is required.

The potential impact on fish behaviour could be of high intensity (particularly in the near-field of the airgun

array), over the short-term (with duration of the effect being less than or equal to the duration of exposure,

although these vary between species and individuals, and are dependent on the properties of the received

sound), but limited to the immediate survey area. Any observed effects are unlikely to persist for more than

a few days after termination of airgun use. Consequently it is considered to be of low significance without

mitigation and VERY LOW significance with mitigation.

Spawning and recruitment

Fish populations could be further impacted if behavioural responses result in deflection from migration paths

or disturbance of spawning. If fish on their migration paths or spawning grounds are exposed to powerful

external forces, they may be disturbed or even cease spawning altogether thereby affecting recruitment to

fish stocks. The magnitude of effect in these cases would depend on the biology of the species and the

extent of the dispersion or deflection. Studies undertaken experimentally exposing the eggs and larvae of

various fish species to airgun sources, however, identified mortalities and physiological injuries at very close

range (<5 m) only.

Although the proposed survey area overlaps with the summer to autumn spawning area for anchovy,

pilchard and horse mackerel (see Figure 4.8), it would primarily be conducted at depths in excess of 150 m

within the far-field range. In addition, considering the spatial extent of the spawning areas, the wide range

over which the potentially affected species occur, the low frequency and short duration of the proposed

seismic survey, and that migration routes do not constitute narrow restricted paths, the impact is considered

to be of low significance without mitigation and VERY LOW significance with mitigation.

Masking of environmental sounds and communication

Fish deliberately produce sounds by three processes, including by stridulation (caused by friction of adjacent

skeletal components), by vibration of the swimbladder, or by rapid head movement. Chorus sounds range

across frequencies higher than the majority of produced seismic survey energy, but some frequency overlap

may occur.

Communication and the use of environmental sounds by fish in the offshore environment off the Namibian

coast are unknown. Impacts arising from masking of sounds are expected to be of low intensity due to the

duty cycle of seismic surveys in relation to the more continuous biological noise. Such impacts would occur

across the immediate survey area and for the duration of the survey and are consequently considered of

VERY LOW significance both with and without mitigation.




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Indirect impacts due to effects on predators or prey.

The assessment of indirect effects of seismic surveys on fish is limited by the complexity of trophic pathways

in the marine environment. The impacts are difficult to determine and would depend on the diet make-up of

the fish species concerned and the effect of the seismic survey on the diet species. Indirect impacts of

seismic surveying could include attraction of predatory species such as sharks and tuna to pelagic fish

stunned by seismic noise. In such cases where feeding behaviour overrides a flight response to seismic

survey sounds, injury or mortality could result if the seismic sound source is initiated at full power in the

immediate vicinity of the feeding predators.

Little information is available on the feeding success of large migratory species in association with seismic

survey noise. Large pelagic species are known to aggregate around seamounts and bathymetric features to

feed, such as the Walvis Ridge. However, considering the extensive range over which large pelagic fish

species potentially feed in relation to the immediate survey area, and the low abundance of pelagic shoaling

species that constitute their main prey, the impact is likely to be of VERY LOW significance with or without

mitigation.

Impacts are summarised in Table 5.12.

Mitigation

• Implement a “soft-start” procedure of a minimum of 20 minutes’ duration when initiating seismic

surveying. This requires that the sound source be ramped from low to full power rather than initiated

at full power, thus allowing a flight response to outside the zone of injury or avoidance. Such a “soft-

start” procedure would allow fish to move out of the survey area and thus avoid potential physiological

injury as a result of seismic noise;

• All breaks in airgun firing of longer than 20 minutes must be followed by a “soft-start” procedure of at

least 20 minutes prior to the survey operation continuing. Breaks of shorter than 20 minutes should be

followed by a “soft-start” of similar duration;

• Airgun firing should be terminated if, in the unlikely event, mass mortalities of fish are observed as a

direct result of shooting.

Table 5.12: Impact of seismic noise on fish.



Without mitigation Local Short-term High Probable Low Medium

With mitigation Local Short-term Low to

Medium Improbable VERY LOW Medium



With mitigation Local Short-term Medium Improbable VERY LOW Medium

Spawning and recruitment



Medium Improbable VERY LOW Medium

Masking sounds and communication

Without mitigation Local Short-term Low Improbable Very Low Low

With mitigation Local Short-term Low Improbable VERY LOW Low




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October 2017


Indirect impacts



5.3.4 POTENTIAL IMPACTS ON SEABIRDS

Description of effect

Among the marine avifauna occurring along the southern Namibian coast, it is only the species that feed by

plunge-diving or that rest on the sea surface (non-diving), which may be affected by the underwater noise of

seismic surveys. Potential impacts of seismic pulses to seabirds could include physiological injury,

behavioural avoidance of the seismic survey area and indirect impacts due to effects on predators or prey.

Assessment

Impacts on seabirds are summarised in Table 5.13 (diving seabirds) and 5.14 (non-diving seabirds).


Diving seabirds are all highly mobile and would be expected to flee from approaching sound sources at

distances well beyond those that could cause physiological injury, although initiation of a sound source at

full power in the vicinity of diving seabirds could result in injury or mortality where feeding behaviour override

a flight response to seismic survey sounds.

Of the plunge diving species that occur along the Namibian coastline, only the Cape gannet regularly feeds

as far offshore as 100 km. African penguins are known to forage as far as 60 km offshore, with the rest

foraging in nearshore areas up to 40 km from the coast. The nearest nesting grounds for Gannets and

African Penguins are at Ichaboe Island, Halifax and Possession Islands, which lie over 500 km to the south

of the proposed survey area. Thus encounters with these two species are unlikely. The Kunene River

mouth and coastline south thereof is an important habitat for Damara Terns. However, encounter rates are

likely to be low, as Damara Terns feed primarily in inshore waters, sheltered bays and lagoons, well inshore

of the survey area.

The potential for physiological impact of seismic noise on diving bird species is considered to be of low

intensity and would be limited to the immediate survey area and survey duration (short-term). The potential

physiological impact on diving species is considered to be of VERY LOW significance with and without

mitigation.

No physiological injury or mortality impacts would occur in non-diving seabirds, as flying seabirds are highly

mobile and would be expected to flee from approaching seismic noise sources at distances well outside of

that that could cause physiological injury. The potential physiological impact on non-diving species is

considered to be INSIGNIFICANT.


Diving birds would be expected to hear seismic sounds at considerable distances, as they have

good hearing at low frequencies (which coincide with seismic shots). Response distances are, however,

speculative as no empirical evidence is available. Avoidance behaviour by diving seabirds would only last

for the duration of the survey period and would be limited to the vicinity of the operating airgun within the

immediate survey area. Should seismic operations encounter diving birds, the impact is likely to be of

medium to high intensity. Due to the low likelihood of encountering diving birds in the survey area, the

potential impact on the behaviour of diving seabirds is considered to be of low significance without mitigation

and of VERY LOW significance with mitigation.




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The behavioural impact of seismic noise on non-diving seabirds is considered to be INSIGNIFICANT.

Indirect impacts due to effects on predators or prey

The assessment of indirect effects of seismic surveys on diving seabirds is limited by the complexity of

trophic pathways in the marine environment and depends on the diet make-up of the bird species concerned

and the effect of seismic surveys on the diet species. No information is available on the feeding success of

seabirds in association with seismic survey noise. With few exceptions, most plunge-diving birds forage on

small shoaling fish prey species relatively close to the shore and are unlikely to feed extensively in offshore

waters that would be targeted during the proposed seismic survey.

The broad ranges of potential fish prey species (in relation to potential avoidance patterns of seismic surveys

of such prey species), the low likelihood of encountering diving birds and extensive ranges over which most

seabirds feed suggest that indirect impacts would be of VERY LOW significance with and without mitigation.

Mitigation

Recommendations to mitigate the potential impacts on seabirds are the same as recommended for fish

(see Section 5.3.3). In addition, the following is recommended:

• An area with a radius of 500 m be scanned (visually during the day) by an independent on-board

observer or Marine Mammal Observer (MMO) for the presence of diving seabirds prior to the

commencement of “soft-starts”. “Soft-start” procedures must only commence once it has been

confirmed that there is no significant diving seabird activity within 500 m of the vessel;

• Daylight observations of the survey area should be carried out by an independent on-board observer

or MMO. Seabird incidence and behaviour should be recorded. Any attraction of predatory seabirds

by mass disorientation and stunning of fish as a result of seismic survey activities, and incidents of

feeding behaviour near the hydrophone streamer, should be recorded;

• If obvious mortality or injuries to seabirds are observed, the survey should be terminated temporarily

until such time as the MMO confirms that the risk to diving seabirds has been significantly reduced.

It is important that the MMOs’ decisions to terminate firing are made confidently and expediently.

In this light it is suggested that MMOs advise when the survey is to be terminated and a log of all

termination decisions is kept (for inclusion in both daily and close out reports);

• Lighting on-board the survey vessel should be reduced to minimum safety levels to minimise stranding

of pelagic seabirds on the survey vessel at night. All stranded seabirds must be retrieved and

released during daylight hours; and

• All data recorded by the MMO should form part of a survey close-out report. Furthermore, daily

reports should be forwarded to the necessary stakeholders to ensure compliance with the mitigation

measures.

Table 5.13: Impact of seismic noise on diving seabirds.



Without mitigation Local Short-term Low Improbable Very Low Medium



Without mitigation Local Short-term Medium to

High Improbable Low Medium





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October 2017


Indirect impacts



Table 5.14: Impact of seismic noise on non-diving seabirds.



Without mitigation Local Short-term Zero Improbable Insignificant High

With mitigation Local Short-term Zero Improbable INSIGNIFICANT High


Without mitigation Local Short-term Zero Improbable Insignificant High

With mitigation Local Short-term Zero Improbable INSIGNIFICANT High

5.3.5 POTENTIAL IMPACTS ON TURTLES


The most likely impacts to turtles from seismic survey operations include physiological injury (including

disorientation) or mortality from seismic noise and collision with or entanglement in towed seismic apparatus,

behavioural avoidance of the seismic survey area and indirect effects due to the effects of seismic sounds on

prey species.

Assessment

Although three species of turtles occur along the coast of Namibia, it is only the Leatherback turtle that is

likely to be encountered in deeper waters. The occurrence of non-breeding Green turtles has been reported

from the Kunene River mouth. The survey area would be approximately 27 km from the river mouth at its

closest point. Abundances of both species are likely to be extremely low comprising occasional migrants.

Impacts on turtles are summarised in Table 5.15.


The overlap of turtle hearing sensitivity with the higher frequencies produced by airguns suggest that turtles

may be considerably affected by seismic noise. Recent evidence, however, suggests that turtles only detect

airguns at close range (<10 m) or are not sufficiently mobile to move away from approaching airgun arrays

(particularly if basking). Initiation of a sound source at full power in the immediate vicinity of a swimming or

basking turtle would be expected to result in physiological injury. The potential impact could therefore be of

high intensity, but remain within the short-term.

There is also the potential for collision between adult turtles and the seismic vessel or entanglement of turtles

in the towed seismic equipment and surface floats. The potential impact on turtles is highly dependent on

the abundance and behaviour of turtles in the survey area at the time of the survey. The abundance of

turtles in the survey area is low. Thus, the likelihood of encountering turtles during the proposed survey is

also expected to be low.




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The potential physiological impact on turtles and the potential for mortality through collision or entanglement

is considered to be of low significance without mitigation and of VERY LOW significance with mitigation.


Behavioural changes by turtles in response to seismic sounds range from startle response and avoidance by

fleeing an operating sound source, through to apparent lack of movement away from active airgun arrays.

The impact of seismic sounds on turtle behaviour is of high intensity, but would persist only for the duration

of the survey, and be restricted to the survey area.

Given the general extent of turtle migrations relative to the survey area and their low abundance in the

survey area, the impact of seismic noise on turtle migrations is deemed to be of low significance without

mitigation and VERY LOW with mitigation.


Breeding adults of sea turtles undertake large migrations between distant foraging areas and their nesting

sites, which occur over 1 000 km north-west of the survey area in the Republic of Congo, Gabon and

Equatorial Guinea. Although it is speculated that turtles may use acoustic cues for navigation during

migrations, information on turtle communication is lacking. There is no information available in the literature

on the effect of seismic noise in masking environmental cues and communication in turtles, but their low

abundance in the survey area would suggest that the potential significance of this impact would be

INSIGNIFICANT.

Indirect impacts due to effects on prey species

Leatherback turtles feed on jellyfish, which are pelagic and, therefore, have a naturally temporally and

spatially variable distribution. Adverse modification of such pelagic food sources would thus be insignificant,

and the effect of a seismic survey on the feeding behaviour of turtles is thus expected to be VERY LOW both

with and without mitigation.

Mitigation

Recommendations to mitigate the potential impacts on turtles are the same as recommended for seabirds


• The MMO should record incidence of turtles and their responses to seismic shooting, including

position, distance from the vessel, swimming speed and direction and obvious changes in behaviour

(e.g. startle responses or changes in surfacing/diving frequencies, breathing patterns, etc.).

It is important that the identification and behaviour of the animals are recorded accurately along with

sound levels. MMOs should, therefore, have experience in identification and differentiation of marine

species, as well as observation techniques. The observer should also record (1) all “soft-starts” and

pre-firing observation regimes, (2) incidence of feeding behaviour of predators within the hydrophone

streamers, and (3) sightings of any injured or dead protected species, regardless of whether the injury

or death was caused by the seismic vessel itself. If the injury or death was caused by a collision with

the seismic vessel, the date and location (coordinates) of the strike and the species or a description of

the animal should be recorded;

• Seismic shooting must be temporarily terminated when obvious negative changes to turtle behaviour is

observed, if animals are observed within 500 m of the operating airguns and appear to be approaching

the firing airguns or there is mortality or injuries to turtles as a direct result of the survey; and

• ‘Turtle-friendly’ tail buoys should be used by the survey contractor or existing tail buoys should be fitted

with either exclusion or deflector 'turtle guards'.




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October 2017

Table 5.15: Impact of seismic noise on turtles.



Without mitigation Local Short-term High Improbable Low Medium



Without mitigation Local Short-term High Improbable Low High

With mitigation Local Short-term Low Improbable VERY LOW High


Without mitigation Local Short-term Very Low Improbable Insignificant Low

With mitigation Local Short-term Very Low Improbable INSIGNIFICANT Low

Indirect impacts



5.3.6 POTENTIAL IMPACTS ON SEALS


Review of the available literature suggests that potential impacts of seismic pulses to Cape fur seals could

include physiological injury, behavioural avoidance of the seismic survey area, masking of environmental

sounds and underwater communication and indirect impacts due to effects on predators or prey.

Assessment

The closest seal colonies to the proposed survey are located at Cape Frio and Möwe Bay, approximately 60

km and 200 km south, respectively. The proposed survey area thus falls within the foraging range of seals

(up to 220 km offshore) from these nearby colonies and encounter rates are likely to be high. Impacts on the

Cape fur seal are summarised in Table 5.16.


The potential for physiological injury to seals from seismic noise is expected to be low as it is assumed that

highly mobile creatures such as fur seals would avoid severe sound sources at levels well below those at

which discomfort occurs, although Cape fur seals have been recorded to approach operational seismic

survey gear. Their tendency to swim at or near the surface would expose them to reduced sound levels

when in close proximity to an operating airgun array.

The potential impact of physiological injury to seals as a result of seismic noise is therefore deemed to be of

high intensity and would be limited to the immediate survey area, although injury could extend beyond the

survey duration. The significance of the impact is considered to be low without mitigation and VERY LOW

with mitigation.




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October 2017


Although partial avoidance (to less than 250 m) of operating airguns has been recorded for some seal

species, Cape fur seals appear to be relatively tolerant to loud noise pulses and, despite an initial startle

reaction, individuals quickly revert back to normal behaviour.

The potential impact of seal behaviour in response to the proposed seismic survey is thus considered to be

of low to medium intensity and limited to the immediate survey area and duration. The significance of the

impact is considered to be of VERY LOW significance with or without mitigation.


The fact that seals have acute underwater directional hearing suggests that sound is used in orientating

underwater. True seals have been shown to use underwater vocalisation in both orientation and

communication. The use of underwater sounds for environmental interpretation and communication by Cape

fur seals is unknown, although masking is likely to be limited by the low duty cycle of seismic pulses (one

pulse every approximately 10 to 15 seconds). The impacts of masking are considered of VERY LOW

significance with and without mitigation.

Indirect impacts due to effects on predators or prey.

The assessment of indirect effects of seismic surveys on Cape fur seals is limited by the complexity of

trophic pathways in the marine environment and depends on the diet make-up of the species (and the

flexibility of the diet) and the effect of the seismic survey on the diet species. The broad ranges of fish prey

species (in relation to the avoidance patterns of seismic surveys of such prey species) and the extended

foraging ranges of Cape fur seals suggest that indirect impacts due to effects on predators or prey would be

of VERY LOW significance with and without mitigation.

Mitigation

Recommendations to mitigate the potential impacts on seals are similar to that recommended for turtles

(see Section 5.3.5), except that:

• “Soft-start” procedures should be allowed to commence, if after a period of 30 minutes seals are still

within 500 m of the airguns;

• Airgun firing should be terminated temporarily if any obvious negative changes to seal behaviour is

observed or there is any obvious mortality or injuries to seals as a direct result of the survey; and

• The MMO’s daily report should record general seal activity, numbers and any noticeable change in

behaviour.

Table 5.16: Impact of seismic noise on seals.




With mitigation Local Short-term Low Probable VERY LOW Medium


Without mitigation Local Short-term Low to

Medium Probable Very Low High

With mitigation Local Short-term Low Probable VERY LOW High




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October 2017





Indirect impacts

Without mitigation Local Short-term Low Probable Very Low High


5.3.7 POTENTIAL IMPACT ON CETACEANS (WHALES AND DOLPHINS)


Review of the available literature suggests that potential impacts of seismic pulses to whales and dolphins

could include physiological injury, behavioural avoidance of the seismic survey area, masking of

environmental sounds and communication and indirect impacts due to effects on prey.

Assessment

A wide diversity of cetaceans (whales and dolphins) occurs off the northern Namibian coast. The terms

whales and dolphins relate to the size of cetacean species, but the group can best be divided into

odontocete (toothed whales and dolphins) that are resident or migratory and mysticete (baleen whales) that

are largely migratory. Marked differences occur in the hearing capabilities of odontocete cetaceans and

mysticete cetaceans. Mysticete hearing is centred at below 1 kHz, overlapping the highest peaks of the

power spectrum of airgun sounds and consequently these animals may be more affected by disturbance

from seismic surveys. Odontocete hearing is centred at frequencies of between 10 and 100 kHz. These

species may react to seismic shots at long ranges, but hearing damage from seismic shots is only likely to

occur at close range.

Impacts on mysticete cetaceans and odontocete cetaceans are summarised in Tables 5.17 and 5.18,

respectively.


Physiological injury to cetaceans can result from exposure to high sound levels through a number of

avenues, including trauma to both auditory and non-auditory tissues as shifts of hearing threshold

(as permanent (PTS) or temporary threshold shifts (TTS)), direct tissue damage, acoustically induced

decompression sickness or other non-auditory physiological effects.

Typical sound source levels of 243-249 dB re 1 µPa @1 m exceed the source levels required for hearing

damage (PTS and TTS) in cetaceans. Available information suggests that the animal would need to be in

close proximity to operating airguns to suffer physiological injury, and being highly mobile it is assumed that

they would avoid sound sources at distances well beyond those at which injury is likely to occur. However,

avoidance may be complicated by the multipath nature of sound in the ocean. Mitigation involving a “soft-

start” procedure would help alert cetaceans to the increasing sound level and promote movement away from

the sound source. Deep-diving cetacean species may, however, be more susceptible to acoustic injury,

particularly in the case of seafloor-focussed seismic surveys, where the downward focussed impulses could

trap deep diving cetaceans within the survey pulse, as escaping towards the surface would result in

exposure to higher sound level pulses.




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October 2017

Available information suggests that baleen whales and the larger toothed whales would be very receptive to

the sound produced by seismic airgun arrays and consequently this group may be more affected by this type

of disturbance than smaller toothed whales. Encounter rates with the various cetacean species within the

survey area is presented in Section 4.3.8.1 and is not repeated here.

The impact of potential physiological injury to both mysticete and odontocete cetaceans as a result of high-

amplitude seismic sounds is deemed to be of high intensity, but would be limited to the immediate vicinity of

operating airguns within the survey area. The proposed survey is scheduled to commence in the fourth

quarter of 2017 and continue for up to 10 months. Thus the proposed survey would extend into the key

breeding and migration period from the beginning of June to the end of November, and encounters with

humpback whale mother-calf pairs on their return journey from breeding grounds in equatorial West Africa

are highly likely. Numbers of returning whales peak off Namibia in September. Resident whales and those

making exploratory trips northwards from summer feeding grounds off Lüderitz may also be encountered.

Assuming the survey will be undertaken over a 10-month period through the key migration and breeding

period for whales, the impact is considered to be of medium to high significance without mitigation.

Avoidance of the key migration and breeding period would reduce the impact to LOW significance.


Avoidance of seismic survey activity by cetaceans, particularly mysticete species, begins at distances where

levels of approximately 150 to 180 dB are received, while subtle behavioural responses have been noted at

received levels of 120 dB. Behavioural avoidance of seismic noise by baleen whales is, therefore, highly

likely, but such avoidance is likely to be of minimal impact in relation to the distances of migrations of the

majority of mysticete cetaceans.

The timing of the survey relative to seasonal feeding and breeding cycles (such as those observed in

migrating baleen whales) may influence the degree of stress induced by noise exposure. Of greater concern

than general avoidance of migrating whales is avoidance of critical breeding habitat or areas where mating,

calving or nursing occurs. Displacement from critical habitats is particularly important if the sound source is

located at an optimal feeding or breeding ground or areas where mating, calving or nursing occurs. The

proposed survey area, which is located beyond 150 m water depth, does not overlap with such known

inshore areas. The survey area does, as indicated above, overlap with migration routes of humpback whales

to and from their breeding grounds. Although encounter rates peak during migration periods, humpback and

southern right whales are found in southern African West Coast waters year round, although encounters with

the latter will be unlikely. Other baleen whale species are also found year round or have seasonal

occurrences which are not well known, but existing data shows year-round presence of mysticetes. With the

proposed survey planned to commence in the fourth quarter of 2017, it would extend through the key

migration and breeding period from the beginning of June and the end of November. Thus, interactions with

migrating whales (including mother-calf pairs) are highly likely. Resident whales and those making

exploratory trips northwards from summer feeding grounds may also be encountered. The potential impact

of behavioural avoidance of the seismic survey area by mysticete cetaceans is considered to be of high

intensity, across the survey area and for the duration of the survey. Considering the distribution ranges of

most species of cetaceans and assuming that the survey would extend into the key migration and breeding

period for whales, the impact of seismic surveying is considered of medium to high significance without

mitigation and of LOW significance with mitigation.

Although there is very limited information on the response of odontocete cetaceans to seismic surveys, there

is less evidence of avoidance of seismic surveys by toothed whales (including dolphins). No seasonal

patterns of abundance are known for odontocetes occupying the proposed study area but several species

are considered to be year round residents. Thus encounters with the isolated coastal population of various

species are highly likely. A number of other toothed whale species, however, have a more pelagic

distribution thus occurring further offshore and potentially within the survey area, with species diversity and




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October 2017

encounter rates likely to be highest on the shelf slope. The impact of seismic survey noise on the behaviour

of odontocete cetaceans is considered to be of medium intensity over the survey area and duration. The

overall significance will, therefore, vary between species and consequently ranges between very low and

low before mitigation and VERY LOW with mitigation.


Mysticete cetaceans appear to vocalise almost exclusively within the frequency range of the maximum

energy of seismic survey noise, while odontocete cetaceans vocalise at frequencies higher than these.

As the by-product noise in the mid-frequency range can travel far (at least 8 km), masking of communication

sounds produced by whistling dolphins and blackfish1 is likely. In the migratory baleen whale species,

vocalisation increases once they reach the breeding grounds and on the return journey in December –

January when accompanied by calves, so is likely to be seasonally high in the survey area. The effect of

masking may, however, be reduced by the intermittent nature of seismic pulses. The proposed survey would

extend through the key migration and breeding period from the beginning of June to the end of November,

thus the intensity of impact on baleen whales is likely to range from low (outside migration periods) to high

(during migration periods especially when there are mother-calf pairs) over the survey area, and high in the

case of odontocetes. The significance for mysticetes and odontocetes is rated as medium without mitigation

and LOW with mitigation.


The assessment of indirect effects of seismic surveys on resident odontocetes is limited by the complexity of

trophic pathways in the marine environment and depends on the diet make-up of the species (and their

flexibility in their diet) and the effect of the seismic survey on the diet species. However, it is expected that

both fish and cephalopod prey of toothed whales and dolphins may be affected over a limited area. Although

the majority of baleen whales undertake little feeding while on breeding migrations (relying on blubber

reserves), there is recent evidence that certain upwelling centres may be utilised as low latitude feeding

ground by both Southern Right and Humpback whales during summer. The broad ranges of prey species (in

relation to the avoidance patterns of seismic surveys of such prey species) suggest that indirect impacts due

to effects on prey would be of VERY LOW significance before and after mitigation.

Mitigation

Recommendations to mitigate the potential impacts on cetaceans are similar to that recommended for turtles


• The seismic survey should be planned to avoid the key cetacean migration and breeding period which

extends from the beginning of June to the end of November. Thus, it is recommended that the survey

be undertaken over two seasons to avoid this key cetacean migration and breeding period.

As several of the large whale species remain abundant off the northern Namibian coast during

December and January, it is preferable that the survey exclusion period be extended to the end of

January. However, as this would limit the time allowed for a survey in this area to only 4 months,

additional mitigation would be required should the survey be undertaken during December and

January. This additional mitigation includes the implementation of Passive Acoustic Monitoring (PAM)

technology, which detects animals through their vocalisations, in combination with thermal imaging

cameras2 continuously during survey operations.

1 The term blackfish refers to the delphinids: Melon-headed whale, Killer whale, Pygmy Killer Whale, False Killer Whale, Long-finned

Pilot Whale and Short-finned Pilot Whale. 2 Survey vessels should also be fitted with thermal imaging cameras, which use infrared (IR) technology to detect the heat contrast

between a marine mammal and the ocean. Advanced camera systems are capable of simultaneously monitoring 360° around a vessel

and are capable of detecting smaller odontocetes at distances of several hundred metres, while blows from large baleen whales can be

seen at distances of up several kilometres. The IR camera system offers observations possibilities at night, improved detection during

daylight hours, and also allows precise measurement of the distance of the marine mammal to the seismic vessel.




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October 2017

• If surveying is undertaken between February and end of June (as recommended above), PAM

technology is only require when surveying at night or during adverse weather conditions and thick fog;

• The PAM hydrophone streamer should ideally be towed behind the airgun array to minimise the

interference of vessel noise, and be fitted with two hydrophones to allow directional detection of

cetaceans. In order to avoid unnecessary delays to the survey programme, it is recommended that a

spare PAM cable and sensor are kept on-board should there be any technical problems with the

system. However, if there is a technical problem with PAM during surveying, visual watches must be

maintained by the MMO during the day and thermal imaging cameras must be used at night while

PAM is being repaired;

• “Soft-start” procedures must only commence once it has been confirmed3 that there is no cetacean

activity within 500 m of the vessel. The period of confirmation should be for at least 30 minutes4 prior

to the commencement of the “soft-start” procedures. However, in the case of small cetaceans (< 3 m

in overall length), which are often attracted to survey vessels, the normal “soft-start” procedures

should be allowed to commence, if after a period of 30 minutes small cetaceans are still within 500 m

of the airguns;

• All breaks in airgun firing of longer than 20 minutes must be followed by a 30-minute pre shoot watch

and a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks of

shorter than 20 minutes should be followed by a visual assessment for marine mammals within the

500 m mitigation zone (not a 30-minute pre-shoot watch) and a “soft-start” of similar duration;

• The use of the lowest practicable airgun volume should be defined by the operator and enforced; and


made available, if requested, to the MFMR, MME, NAMCOR and the Namibian Dolphin Project in

order to inform studies of cetacean distribution and timing off the Namibian coast.

Table 5.17: Impact of seismic noise on mysticete cetaceans (baleen whales).



Without mitigation Local Short-term High Probable Medium to High Medium


Medium Probable LOW Medium


Without mitigation Local Short-term High Probable Medium to High High

With mitigation Local Short-term Medium Probable LOW High


Without mitigation Local Short-term Low to High Probable Medium Medium

With mitigation Local Short-term Low Probable LOW Medium


• Dec to end Jan: visually and PAM technology during the day and using PAM and Infra-red technology at night or during periods of

poor daytime visibility.

• Feb to end May: visually during the day and using PAM technology at night or during periods of poor daytime visibility. 4 The JNCC Guidelines state this should be extended to 60 minutes for deep-diving species when surveying in deeper water (>200 m).

However, since the proposed survey is largely inshore of the expected range of sperm whales and sightings in the survey area are

expected to be very low, the recommended 30 minute period is considered adequate.




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October 2017


Indirect impacts

Without mitigation Local Short-term Low Probable Very Low High


Table 5.18: Impact of seismic noise on odontocete cetaceans (toothed whales and dolphins).



Without mitigation Local Short-term High Probable Medium to High Medium


Medium Probable LOW Medium


Without mitigation Local Short-term Medium Probable Very Low to Low

(species specific) High


Medium Probable VERY LOW High


Without mitigation Local Short-term High Probable Medium Medium

With mitigation Local Short-term Low Probable LOW Medium

Indirect impacts



5.4 IMPACT ON OTHER USERS OF THE SEA

5.4.1 POTENTIAL IMPACT ON FISHING INDUSTRY

5.4.1.1 Potential impact on fishing sectors


The impacts on the fishing industry include the likely disruption to fishing operations, loss of access to fishing

grounds during surveying, fish avoidance of the seismic survey area and changes in feeding behaviour (with

duration of the effect being less than or equal to the duration of exposure, although these vary between

species and individuals, and are dependent on the properties of the received sound).

With regard to physical exclusion of fishing vessels from a seismic survey area, a seismic vessel is

considered to be an “offshore installation” and as such it is protected by a 500 m safety zone. In addition to

the statutory 500 m safety zone, a seismic contractor would request a safe operational limit (that is greater

than the 500 m safety zone) that it would like other vessels to stay beyond. Typical safe operational limits for

3D surveys are illustrated in Figure 3.2. The estimated 3 km turning circle radius would also make the

effective area of operation slightly larger than the actual survey acquisition area.




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Studies have demonstrated that seismic surveys may also to lead to reduced catch rates not only in the

immediate vicinity of the airgun but also in a wider area due to fish avoidance of the seismic survey area and

changes in feeding behaviour. Estimates of the distance from the airgun at which a decline in catch rates

has been observed, the duration of that impact and the magnitude of the impact (percentage reduction in

catch rate) varied considerably between studies.

The potential impacts on the various fishing sectors operating off the coast of Namibia are presented below.

Assessment

Demersal trawl sector

The demersal trawl sector (i.e. trawling for fish on the sea floor) targets primarily hake and is Namibia’s most

valuable fishery. Main by-catch species include monkfish, kingklip and snoek. This fishery operates along

the shelf contours between depths of 200 m and 850 m. Based on commercial fishing records, trawling

activity would be expected within the proposed survey area between the 250 m and 600 m isobaths. The

fishery is closed each year for the month of October. The proposed survey (which includes the maximum

zone of disturbance) covers approximately 2 921 km2 or 3.5% of the total trawlable ground available to the

sector. Annual effort expended within the survey area amounts to approximately 3 598 fishing hours (2.4%

of the total) and catch taken amounts to 3 538 tons (3.7% of the total). The potential reduction in catch due

to the influence of the acoustic signal within the maximum zone of disturbance is estimated to be up to

0.1 tonne per day. Thus the total loss over the 10-month survey is estimated to be in the order of 30 tonnes

(note: this is an over estimate as fishing would be able continue in other areas and overall catch may not in

fact be reduced).

The potential impact on the demersal trawl fishery in the survey area is localised and of medium to high

intensity in the short-term. The overall impact is considered to be LOW with and without mitigation

(see Table 5.19). Trawl vessels are restricted in manoeuvrability when gear is deployed. Therefore, direct

communication from the survey vessel would be required in order to request trawl vessels to keep clear of

the survey vessel.

Mid-water trawl sector

The mid-water trawl fishery targets adult horse mackerel. This fishery has the highest volume and catch of

all Namibian fish stocks, although in terms of economic value is the second highest contributor behind the

hake fisheries. The mid-water trawl fleet operates exclusively out of the port of Walvis Bay and fishing

grounds extend from north of 25ºS latitude to the border with Angola and effort is highest in the north. Based

on commercial fishing records, trawling activity would be expected within the proposed survey area between

the 200 m and 1 000 m isobaths. The proposed survey (which includes the maximum zone of disturbance)

covers approximately 5 787 km2 or 17.3% of the total trawlable ground available to the sector. Annual effort

expended within the survey area amounts to approximately 3 553 fishing hours (22.9% of the total) and

catch taken amounts to 32 194 tons (17.1% of the total). The potential reduction in catch due to the

influence of the acoustic signal within the maximum zone of disturbance is estimated to be up to 2.7 tonnes

per day. Thus the total loss over the 10-month survey is estimated to be up to 810 tonnes5.

The potential impact on the mid-water trawl fishery in the survey area is regional and of high intensity in the

short-term. The overall impact is considered to be MEDIUM with and without mitigation (see Table 5.19).

Trawl vessels are restricted in manoeuvrability when gear is deployed. Therefore, direct communication

from the survey vessel would be required in order to request trawl vessels to keep clear of the survey vessel.

The termination of surveying during the key cetacean migration and breeding period from the beginning of

5 Note: this is an over estimate as fishing would be able continue in other areas and overall catch may not in fact be reduced.




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October 2017

June until the end of November would to a certain extent help mitigate this impact, as the months of highest

fishing activity in the survey area are June and July.

Deep-water trawl sector

The deep-water trawl fishery is a small fishing sector directed at the outer Namibian shelf from 400 to

1 500 m water depth targeting orange roughy and alfonsino. Since the proposed survey area does not

overlap with any of the four Quota Management Areas and the fishery is currently closed, there would be NO

IMPACT on this sector.

Small pelagic purse-seine sector

The small pelagic purse-seine fishery targets Benguela sardine and juvenile horse mackerel and was

historically the largest fishery (by volume) in Namibia. Fishing activity occurs primarily northwards of Walvis

Bay to the Angolan border, inshore of the 200 m isobath. The proposed survey area (including the maximum

zone of disturbance) covers approximately 489 km2 or 0.7% of the fishing grounds used by the small pelagic

purse-seine fishery. Average annual catch within the area of operation between 1996 and 2011 amounts to

approximately 0.2% of the total catch landed nationally. The potential reduction in catch due to the influence

of the acoustic signal within the maximum zone of disturbance is estimated to be up to 0.2 tonnes per day.

Thus the total loss over the 10-month survey is estimated to be up to 7.3 tonnes5.

The unlikely impact on the pelagic purse-seine fishery in the survey area is localised and of medium intensity

in the short-term. The overall significance is considered to be VERY LOW with and without mitigation

(see Table 5.19). It is important to note that after the net is deployed the vessel has no ability to manoeuvre

until the net has been fully recovered on board and this may take up to 1.5 hours.

Large pelagic long-line sector

This sector utilises surface long-lines to target migratory pelagic species including albacore tuna, yellowfin

tuna, bigeye tuna, swordfish and various shark species. Effort occurs year-round with lower levels of fishing

effort expected between June and October. Over the period 2008 to 2013, 7.1% of the total effort expended

by the fishery coincided with the proposed survey area (which includes the maximum zone of disturbance),

which is equivalent to an average of 58 lines per year (130 000 hooks). Catch taken within the proposed

survey area amounted to approximately 146 tonnes per year (i.e. 6.4% of the total catch landed by the

sector). The potential reduction in catch due to the influence of the acoustic signal within the maximum zone

of disturbance is estimated to be up to 0.01 tonnes per day. Thus the total loss over the 10-month survey is

estimated to be up to 4 tonnes5.

The significance of the impact of the proposed survey on the large pelagic long-line fishery is expected to be

regional and of high intensity in the short-term. The overall significance is expected to be MEDIUM both with

and without mitigation (see Table 5.19). Since long-lines can be up to 100 km long they pose a potential

hazard to the seismic survey operation in terms of gear entanglements.

Demersal long-line sector

The demersal long-line fishery targets bottom-dwelling species, predominantly hake and is expected to occur

in similar areas used by the hake-directed trawling, i.e. along the entire Namibian coastline at a depth range

of 200 m to 600 m. Fishing activity would be expected throughout the survey area between these depths.

The proposed survey (which includes the maximum zone of disturbance) covers approximately 2 278 km2 or

1% of the ground fished by the sector. Annual effort expended within the survey area between 2000 and

2010 amounts to approximately 18 000 hooks (0.01% of the total effort) and hake catch taken amounts to

1.2 tons (0.01% of the total longline catch). The reduction in catch due to the influence of the acoustic signal

beyond the survey area would be expected to result in a negligible reduction in hake catch over the duration

of the survey, as fishing would be able continue in other areas.




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The impact of the proposed survey on the demersal long-line fishery is localised and of medium intensity in

the short-term. The overall significance of this impact is expected to be VERY LOW both with and without


Tuna pole sector

Poling for tuna (predominantly albacore tuna and a very small amount of skipjack tuna, yellowfin tuna and

bigeye tuna) only occurs in southern Namibian waters. The fishery is seasonal with vessel activity mostly

from January to April and peak catches in February, March and April. Within Namibian waters, the fishery

operates primarily southwards of 25°S between the 200 m and 500 m isobaths and in particular over Tripp

Seamount, well to the south of the proposed survey area. Concerns have been raised by the tuna fishing

industry that seismic survey activities in southern Namibia are linked to reductions in tuna catches. Since the

main fishing grounds occur well to the south of the proposed survey area and there has been no recorded

effort within the proposed survey area, there would be NO IMPACT on this sector.

Traditional line-fish sector

The traditional line fishery is based on only a few species that includes kob, snoek and numerous shark

species. The fishery is limited in extent to around the ports and does not operate much further than 12 nm

(±22 km) offshore due to the operational range of vessels operating within this fishery. Due to the distance

of the proposed survey from the areas fished by the commercial line-fish sector, NO IMPACT is expected on

this fishery.

Deep-sea crab sector

The Namibian deep-sea crab fishery is based primarily on two species of crab, namely spider crab and red

crab. The fishery is currently small, with only four vessels currently operating from Walvis Bay. The fishery

is operational year-round and has a minimum operational depth limit of 400 m. The fishing grounds extend

between the 500 m and 900 m isobaths. The proposed survey area (excluding zones of acoustic

disturbance) covers approximately 2 932 km2 or 14.7% of the total ground fished by the sector. Annual effort

expended within the survey area amounts to approximately 14.2% of the total effort expended by the fishery

and catch taken amounts to approximately 15% of the total landings. Based on current research findings,

there are no anticipated effects of seismic noise on the catchability of crustaceans, therefore, the impact of

the survey on the crab trap fishery relates to physical exclusion from fishing grounds rather than any

significant reduction in catch rates in the wider area of acoustic influence.

The potential impact of the proposed survey on the deep-sea crab fishery is regional and of high intensity in

the short-term. The overall significance of this impact is expected to be MEDIUM both with and without


Rock lobster sector

The West Coast rock lobster is commercially exploited in southern Namibia from the Orange River border in

the south to Easter Cliffs/Sylvia Hill north of Mercury Island and generally to a depth of 80 m. The catch

season is a six-month period with a closed period extending from 1 May to 31 October and highest activity

levels experienced over January and February. The fishery is spatially managed through the demarcation of

catch grounds by management area, the closest of which is situated approximately 820 km south of the

proposed survey area. Thus NO IMPACT is expected on this fishery.

Mitigation

The mitigation measures listed below are unlikely to reduce the significance of potential impacts, but they

would minimise disruptions to survey and fishing operations.

• The operator should engage with the fishing industry (specifically the midwater trawl, large pelagic

long-line and dee-sea crab sectors) to discuss their respective fishing programmes (timing and

location) in order to minimise or avoid disruptions to all parties. The possibility of undertaking

concurrent activities within the seismic survey area should be investigated;




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proposed activities) and the likely implications thereof:

> Fishing industry / associations (including Association of Namibian Fishing Industries, Namibian

Hake Association, Namibian Monk and Sole Association, Midwater Trawling Association of

Namibia, Namibian Tuna and Hake Long-lining Association, Pelagic Fishing Association and

Namibian Crab Association); and

> Other key stakeholders include: MME, MET, MFMR, Directorate of Maritime Affairs, Namibian

Ports Authority, port captains, South African Navy Hydrographic office and the Monitoring,

Control and Surveillance unit in Walvis Bay.

• The operator must request, in writing, that the South African Navy Hydrographic office release a Radio

Navigation Warning for the duration of the seismic survey period and that daily notifications be issued

by Walvis Bay Radio. The notifications should give notice of (1) the co-ordinates of the proposed

survey area, (2) an indication of the proposed survey timeframes and day-to-day location of the survey

vessel(s), and (3) an indication of the 500 m safety zones and the proposed safe operational limits of

the survey vessel(s);

• An independent on-board Fisheries Liaison Officer (FLO) who is familiar with fishery operations in the

area must be appointed for the duration of the survey. The duties of the FLO would be to:






activities; and



and progress.

• The survey vessel should be accompanied by a chase boat.

Table 5.19: Assessment of the potential impact on the fishing industry in the proposed survey

area.


Demersal trawl sector


High

Highly

probable Low High

With mitigation Local Short-term Medium to

High

Highly

probable LOW High

Mid-water trawl and large pelagic long-line sectors

Without mitigation Regional Short-term High Highly

probable Medium High

With mitigation Regional Short-term High Highly

probable MEDIUM High

Small pelagic purse-seine sector

Without mitigation Local Short-term Medium Improbable Very Low High

With mitigation Local Short-term Medium Improbable VERY LOW High




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Demersal long-line sectors

Without mitigation Local Short-term Medium Probable Very Low High

With mitigation Local Short-term Medium Probable VERY LOW High

Deep-sea crab sector

Without mitigation Regional Short-term High Probable Medium High

With mitigation Regional Short-term High Probable MEDIUM High

Deep-sea trawl, tuna pole, traditional line-fish and Rock lobster sectors

NO IMPACT

5.4.1.2 Potential impact on fisheries research


MFMR conducts regular research surveys (biomass) on demersal, mid-water and pelagic fish resources off

the Namibian coastline in order to set the annual TAC. The presence of the seismic vessel and associated

500 m safety zone could interfere with these research surveys should they occur in a similar areas at the

same time. In addition, fish could temporarily avoid the survey area while the seismic source array is active.

Assessment

Demersal trawls

Demersal trawl surveys normally take place over a one month period between January and February. Based

on the 2015 survey, trawls were undertaken between a water depth of 135 m and 600 m. Of the 216 trawls

carried out in the 2015 survey, 11 trawls (5.1%) were undertaken within the proposed survey area. The

potential impact on similar demersal trawl research surveys is considered to be of local extent and of

medium intensity in the short-term. This impact is considered to be of VERY LOW with and without


Acoustic research surveys

Scientific acoustic surveys are carried out between February and March each year to estimate the biomass

of small pelagic species. These surveys cover the Namibian shelf from the coastline to the 500 m depth

contour (and up to the 2 000 m contour northwards of 18°30´S). The research vessel surveys along pre-

determined transects that run perpendicular to depth contours (East-West / West-East direction). Acoustic

research survey activity could be expected within the proposed seismic survey area to a maximum depth of

2 000 m. Approximately 18 of a total of 66 survey transects undertaken in 2014 coincide with the proposed

survey area, which is equivalent to 27.3% of the total number of transects surveyed during a single survey.

The potential impact on acoustic research surveys is considered to be of regional extent and of high intensity

in the short-term. This unlikely impact is considered to be of medium significance without mitigation and

LOW with mitigation (see Table 5.20).

Mitigation

The most effective means of mitigation would be to ensure that the proposed seismic survey does not

coincide with any proposed research surveys in the area. It is recommended that some time in advance of

survey commencement, the operator engage with the MFMR (fisheries research managers) to discuss their

respective survey programmes (seismic and fisheries research) and negotiate the timing and location thereof




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in order to minimise or avoid disruptions to both parties. The possibility of undertaking concurrent activities

within the seismic survey area should be investigated.

Table 5.20: Assessment of the potential impact on fisheries research in the proposed survey area.


Demersal trawl research surveys

Without mitigation Local Short-term Medium Probable Low High


Medium Probable VERY LOW High

Acoustic research surveys

Without mitigation Regional Short-term High Probable Medium High

With mitigation Regional Short-term Medium Probable LOW High

5.4.2 IMPACT ON MARINE TRANSPORT ROUTES


The acquisition of high quality data requires that the position of the seismic vessel is accurately known and

that the seismic vessel would need to travel in uninterrupted lines. For this reason the seismic vessel

together with its towed arrays and hydrophone streamers is considered a fixed marine feature that is to be

avoided by all other vessels (COLREGS, 1972, Part A, Rule 10), as indicated in Section 3.2.5. In terms of

the Petroleum (Exploration and Production) Act (No. 2 of 1991) a seismic vessel is considered to be an

“offshore installation” and as such it is protected by a 500 m safety zone.

The presence of the seismic vessels with the associated 500 m safety zone and proposed safe operational

limits could interfere with shipping in the area. Typical safe operational limits are illustrated in Figure 3.2.

Assessment



the proposed survey area (see Figure 4.32). Fishing vessels would be encountered over the majority of the

survey area (refer to Section 5.4.1 for the potential impact on various fishing sectors).

The displacement of marine shipping would be limited to the extreme near vicinity of the seismic vessel and

the displacement would be no greater than that associated with any other vessels restricted in their

manoeuvrability. The impact on shipping traffic in the proposed survey area is considered to be localised

(at any one time) and of high to medium intensity in the short-term. However, due to the total extent of the

survey area, the significance of this impact is assessed to be slightly higher at low without mitigation and

VERY LOW with mitigation (see Table 5.21).

Mitigation

Recommendations to mitigate the potential impacts on marine transport routes are similar to that

recommended for the fishing industry (see Section 5.4.1). In addition, the following is recommended:

• The seismic and support vessels must be certified for seaworthiness through an appropriate

internationally recognised marine certification programme (e.g. Lloyds Register, Det Norske Veritas).

The certification, as well as existing safety standards, requires that safety precautions would be taken

to minimise the possibility of an offshore accident;




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o A support / chase vessel with an on-board FLO who is familiar with the fisheries expected in the

area;

o The existence of an internationally agreed 500 m safety zone around the survey vessels;

o Cautionary notices to mariners; and

o Access to current weather service information.






• The operator must formally notify the MME (Commissioner for Petroleum Affairs6) of the survey

location, commencement date and anticipated duration; and

• Report any emergency situation to the Commissioner for Petroleum Affairs.

Table 5.21: Assessment of interference with marine transport routes.


Without mitigation Local Short-term High to

Medium

Highly

probable Low Medium


probable VERY LOW Medium

5.4.3 POTENTIAL IMPACT ON MARINE MINING


Mining and associated activities (e.g. prospecting and refuelling) would be required to avoid the 500 m safety

zone and proposed safe operational limits around the seismic vessels, which could cause a disruption to

marine mining and associated activities.

Assessment

The proposed survey area overlaps with a number of offshore EPLs and Mining Licences (see Figure 4.33).

However, current activities in the EPLs are minimal to non-existent with the only active operations

being diamond mining south of Lüderitz. There is also a proposal to mine phosphate in a licence

area approximately 120 km south of Walvis Bay, well to the south of the proposed survey area. Thus NO

IMPACT is anticipated on marine mining.

Mitigation

No mitigation is considered necessary.

6 The Commissioner is obliged to notify all relevant parties and cause such offshore location to be published in a “Notice to Mariners” in

terms of Regulation 15(b) of the Petroleum (Exploration and Production) Act 2 of 1991), as published by the South African Navy Hydrographic office in Cape Town.




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5.4.4 POTENTIAL IMPACT ON OIL AND GAS EXPLORATION


The proposed seismic survey activities could affect other oil and gas exploration activities in the surrounding

licence blocks (see Figure 1.1 and 4.33).

Assessment

The proposed survey area overlaps with numerous offshore licence blocks (see Figure 1.1). NAMCOR has

advised that it will contact directly affected licence holders in order to inform them that Spectrum is proposing

to undertake a 3D seismic survey over their block(s). In addition to those blocks directly affected by actual

surveying, the vessel would traverse other blocks during line changes, which may have an impact on

neighbouring operators.

Should any of the other operators adjoining the survey area undertake any exploration activities at a similar

time there could be a localised impact, of medium to high intensity in the short-term. The significance of this

impact is therefore assessed to be low without mitigation and VERY LOW with mitigation (see Table 5.22).

Mitigation

The operator is to engage timeously with adjacent licence holders in order to reduce the risk of delay to, or

interference with each other’s exploration activities. The relevant licence holders should be notified

timeously of the proposed seismic survey, including:

• the co-ordinates of the proposed survey area;

• an indication of the proposed survey timeframes and day-to-day location of the seismic vessel; and

• an indication of the proposed safe operational limits of the survey vessel.

Table 5.22: Assessment of impact on oil and gas exploration.



High Improbable Low Medium





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6 CONCLUSIONS AND RECOMMENDATIONS

Spectrum has applied to undertake a 3D seismic survey in the Walvis Basin off the coast of northern

Namibia, under a Multi-Client Agreement with NAMCOR. The proposed 3D seismic survey area is

12 940 km2 in extent and is situated roughly between the Namibian – Angolan border (17º 14’ S) and

18º 08’ S. Water depths in the survey area range from approximately 150 m in the east to depths greater

than 4 000 m in the west. The survey area is located 27 km from shore at its closest point. Although survey

commencement would ultimately depend on when clearance is obtained from MME and vessel availability,

Spectrum proposes to commence with the 3D seismic survey in the fourth quarter of 2017. It is anticipated

that the proposed 3D seismic would take in the order of nine (9) to ten (10) months to complete.

Spectrum appointed SLR to investigate the baseline conditions in the proposed survey area and to assess

the potential impacts of the proposed survey. Specialists were appointed to address the two key issues,

namely the effects on the fishing industry and on marine fauna. The findings of the specialist studies and

other relevant information have been integrated and synthesised into this document.

This chapter summarises the key findings of the study and presents mitigation measures that should be

implemented for the proposed seismic survey.

6.1 CONCLUSIONS

A summary of the assessment of potential environmental impacts associated with the proposed seismic

survey is provided below and in Table 6.1.

The majority of the impacts associated with the seismic survey would be of short-term duration and limited to

the immediate survey area. As a result, the majority of the impacts are considered to be of INSIGNIFICANT

to LOW significance after mitigation.

The two key issues associated with the proposed seismic survey relate to:

• The potential impact on marine mammals (physiological injury and behavioural avoidance) as a result

of seismic noise; and

• The potential impact on the fishing industry (vessel interaction, disruption to fishing operations and

reduced catch) due to the presence of the survey vessel with its associated safety zone, potential fish

avoidance of the survey area and changes in feeding behaviour.

Assuming the 10-month survey would extend into the key cetacean migration and breeding period from the

beginning of June to the end of November, the impact on cetaceans is considered to be of medium to high

significance without mitigation. In order to mitigate this impact, it is strongly recommended that the proposed

seismic survey programme be undertaken in two phases in order to avoid this key period. As several of the

large whale species (including mother-calf pairs) remain abundant off the northern Namibian coast during

December and January, it is further recommended that PAM technology, which detects animals through their

vocalisations, in combination with thermal imaging cameras be continuously implemented should surveying

occur during this period. Various other measures are recommended to further mitigate the potential impact

on cetaceans, including a 30-minute pre-watch period, “soft-start” procedure, temporary termination of

survey, etc. The recommended approach of undertaking the survey over two seasons, along with the other

proposed mitigation, would reduce potential impacts on cetaceans to VERY LOW to LOW.

Although most of the impacts on cetaceans are assessed to have VERY LOW to LOW significance with

mitigation, the impact could be of higher significance due to the limited understanding of how short-term

effects of seismic surveys relate to longer term impacts. For example, if a sound source displaces a species

from an important feeding or breeding area for a prolonged period, impacts at the population level could be




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more significant. This said, the southern right and humpback whale populations are reported to be

increasing by 7% and 5% per annum, respectively, over a time when seismic surveying frequency has

increased, suggesting that, for these populations at least, there is no evidence of long-term negative change

to population size as a direct result of seismic survey activities.

The key fishing sectors in the vicinity of the proposed survey area, based on commercial fishing records, are

the mid-water trawl, large pelagic long-line and deep-sea crab sectors. The potential impact on these

sectors over a 10-month period is considered to be of MEDIUM significance with mitigation. Although the

potential impact on the other sectors (including demersal trawl, small pelagic purse-seine, demersal long-line

and deep-sea crab sectors) ranges from VERY LOW to LOW significance with mitigation, if fish avoid the

survey area and / or change their feeding behaviour it could have a more significant impact on these sectors.

Research has, however, shown that behavioural effects are generally short-term with duration of the effect

being less than or equal to the duration of exposure, although these vary between species and individuals,

and are dependent on the properties of the received sound. Any interaction between the seismic survey

vessels and fishing vessels could also increase the significance of the impact of these fisheries. Thus it is

important that the operator engage timeously with the fishing industry prior to and during the surveys in order

to minimise any interaction.

There would be NO IMPACT on the rock lobster sector, tuna pole, deep-sea trawl and traditional line-fish

sectors.

Prior to survey commencement it is recommended that key stakeholders (including fishing industry

associations) are informed of the proposed survey details (including navigational co-ordinates of the survey

areas, and timing and duration of proposed activities) and the likely implications thereof (500 m safety zone

and proposed safe operational limits). In addition, it is recommended that Radio Navigation Warnings and

Notices to Mariners are provided regularly during survey operations. The placement of an on-board FLO

would also help ensure that ongoing communication (via daily reports) is maintained between the survey

vessels and the fishing industry and other users of the sea. This proposed regular communication with

fishing vessels in the vicinity of the proposed surveys would minimise the potential disruption to fishing

operations and risk of gear entanglements.

Table 6.1: Summary of the significance of potential impacts related to the proposed 3D seismic


possible and / or considered necessary, thus significance rating remains).


(with mitigation)

Significance

Without mitigation

With mitigation

Normal seismic / support vessels and helicopter operation:

Emissions to the atmosphere Definite VL VL

Deck drainage into the sea Highly probable VL VL

Machinery space drainage into the sea Highly probable VL VL

Sewage effluent into the sea Highly probable VL VL

Galley waste disposal into the sea Highly probable VL VL

Solid waste disposal into the sea Improbable Insig. INSIG.

Accidental oil spill during

bunkering / refuelling

Within port limits Improbable Insig. INSIG.

Offshore Improbable L VL

Noise from seismic and support vessel operations Probable VL VL*

Noise from helicopter operation Improbable L-M VL

Impact of seismic noise on marine fauna:

Plankton Probable VL VL*




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(with mitigation)

Significance

Without mitigation

With mitigation

Invertebrates Physiological injury Probable VL VL*

Behavioural avoidance Probable VL VL*

Fish Physiological injury Improbable L VL


Spawning and recruitment Improbable L VL

Masking sound and communication Improbable VL VL


Diving seabirds Physiological injury Improbable VL VL



Non-diving seabirds Physiological injury Improbable Insig. INSIG.

Behavioural avoidance Improbable Insig. INSIG.

Turtles Physiological injury Improbable L VL


Masking sound and communication Improbable Insig. INSIG.


Seals Physiological injury Probable L VL

Behavioural avoidance Probable VL VL

Masking sound and communication Probable VL VL


Mysticetes Cetaceans Physiological injury Probable M - H L

Behavioural avoidance Probable M - H L



Odontocetes Cetaceans Physiological injury Probable M - H L

Behavioural avoidance Probable VL - L VL



Impact on other users of the sea:

Fishing industry Demersal trawl Highly probable L L

Mid-water trawl Improbable M M

Deep-sea trawl Improbable NO IMPACT

Small pelagic purse-seine Improbable VL VL

Large pelagic long-line Highly probable M M

Demersal long-line Highly probable VL VL

Fishing industry (cont.) Tuna pole Improbable NO IMPACT

Traditional line-fish Improbable NO IMPACT

Deep-sea crab Improbable M M

Rock lobster Improbable NO IMPACT

Fisheries

research

Demersal Probable VL VL

Acoustic Probable M L

Marine transport routes Highly probable L VL

Marine mining and

exploration

Marine mining Improbable NO IMPACT

Oil and gas exploration Improbable L VL

H=High M=Medium L=Low VL=Very low Insig. = Insignificant N/A=Not

applicable

All impacts

are negative




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6.2 RECOMMENDATIONS

6.2.1 COMPLIANCE WITH EMP AND MARPOL STANDARDS

All phases of the proposed seismic survey programme (including pre-establishment phase, establishment

phase, operational phase, and decommissioning and closure phase) must comply with the EMP presented in

Chapter 7. In addition, the seismic and support vessels must ensure compliance with MARPOL 73/78

standards.

6.2.2 SURVEY TIMING AND SCHEDULING

The seismic survey programme should be undertaken over two seasons in order to avoid the key cetacean

migration and breeding period which extends from the beginning of June to the end of November (i.e. the

survey period is from December to May). As several of the large whale species (including mother-calf pairs)

remain abundant off the northern Namibian coast during December and January, it is further recommended

that PAM technology, which detects animals through their vocalisations, in combination with thermal imaging

cameras be continuously implemented should surveying occur during this period.

It is also recommended that the operator engage with the fishing industry (specifically the midwater trawl,

large pelagic long-line and dee-sea crab sectors) and MFMR (fisheries research managers) well in advance

of commencement in order to discuss their respective fishing and research survey programmes (timing and

location) in order to minimise or avoid disruptions to all parties. The possibility of undertaking concurrent

activities within the seismic survey area should be investigated.

6.2.3 SEISMIC SURVEY PROCEDURES

6.2.3.1 PAM technology

PAM technology, which detects animals through their vocalisations, must be implemented when surveying at

night or during adverse weather conditions and thick fog. In addition, PAM technology must be implemented

continuously during survey operations if surveying is undertaken in December and January.

The PAM hydrophone streamer should ideally be towed behind the airgun array to minimise the interference

of vessel noise, and be fitted with two hydrophones to allow directional detection of cetaceans. In order to

avoid unnecessary delays to the survey programme, it is recommended that a spare PAM cable and sensor

are kept on-board should there be any technical problems with the system. However, if there is a technical

problem with PAM during surveying, visual watches must be maintained by the MMO during the day and

thermal imaging cameras must be used at night while PAM is being repaired.

6.2.3.2 Thermal imaging cameras

If surveying is undertaken in December and January, survey vessels should also be fitted with thermal

imaging cameras, which use infrared technology to detect the heat contrast between the marine mammal

and the ocean. Advanced camera systems are capable of simultaneously monitoring 360° around a vessel

and are capable of detecting smaller odontocetes at distances of several 100 m, while blows from large

baleen whales can be seen at distances of up several kilometres. The infrared camera system offers




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observations possibilities at night, improved detection during daylight hours, and also allows precise

measurement of the distance of the marine mammal to the seismic vessel.

6.2.3.3 “Soft-start” procedure, pre-watch period and airgun firing

All initiations of seismic surveys must be carried out as “soft-starts” for a minimum of 20 minutes. This

requires that the sound source be ramped from low to full power rather than initiated at full power, thus

allowing a flight response by marine fauna to outside the zone of injury or avoidance. Where possible, “soft-

starts” should be planned so that they commence within daylight hours.

“Soft-start” procedures must only commence once it has been confirmed for a 30-minute period1 that there is

no seabird (diving), turtle or marine mammal activity within 500 m of the vessel. However, in the case of

seals and small cetaceans (< 3 m in overall length), which are often attracted to survey vessels, the normal

“soft-start” procedures should be allowed to commence, if after a period of 30 minutes seals and small

cetaceans are still within 500 m of the airguns.

All breaks in airgun firing of longer than 20 minutes must be followed by a pre-shoot watch (as described

above) and a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks of

shorter than 20 minutes should be followed by a visual assessment for marine mammals within the 500 m

mitigation zone (not a pre-shoot watch) and a “soft-start” of similar duration.

The use of the lowest practicable airgun volume, as defined by the operator, should be defined and

enforced.

During surveying, airgun firing should be terminated when:

• obvious negative changes to turtle, seal and cetacean behaviour is observed;

• turtles or cetaceans are observed within 500 m of the operating airgun and appear to be approaching

the firing airgun; or

• there is mass mortality of fish or mortality / injuries to seabirds, turtles, seals or cetaceans as a direct

result of the survey.

The survey should remain terminated until such time that the time MMO confirms that:

• Turtles or cetaceans have moved to a point that is more than 500 m from the source;

• Despite continuous observation, 30 minutes has elapsed since the last sighting of the turtles or

cetaceans within 500 m of the source; and

• Risks to seabirds, turtles, seals or cetaceans have been significantly reduced.

A log of all termination decisions must be kept (for inclusion in both daily and “close-out” reports).


• Dec to end Jan: visually and PAM technology during the day and using PAM and Infra-red technology at night or during periods

of poor daytime visibility.

• Feb to end May: visually during the day and using PAM technology at night or during periods of poor daytime visibility.




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6.2.3.4 MMO and PAM operator

An independent on-board MMO and, where necessary, a PAM operator must be appointed for the duration

of the seismic survey. They must have experience in seabird, turtle and marine mammal identification and

observation techniques. The duties of the MMO would be to:

Marine fauna:

• Confirm that there is no marine faunal activity within 500 m of the seismic source array prior to

commencing with the “soft-start” procedures;

• Monitor marine faunal activity during daytime surveying;

• Observe and record responses of marine fauna to the seismic survey, including seabird, turtle, seal

and cetacean incidence and behaviour and any mortality or injuries of marine fauna as a result of the

seismic survey. Data capture should include species identification, position (latitude/longitude),

distance from the vessel, swimming speed and direction (if applicable) and any obvious changes in

behaviour (e.g. startle responses or changes in surfacing/diving frequencies, breathing patterns) as a

result of the survey activities;


and

• Request the temporary termination of the seismic survey, as appropriate. It is important that the

MMOs’ decisions to terminate firing are made confidently and expediently;

Other:

• Record meteorological conditions;

• Monitor compliance with international marine pollution regulations (MARPOL 73/78 standards); and

• Prepare daily reports of all observations. These reports should be forwarded to the key stakeholders,

as appropriate.

The duties of the PAM operator would be to:

• Ensure that hydrophone streamers are optimally placed within the towed array;

• Confirm that there is no marine mammal activity within 500 m of the vessel prior to commencing with

the “soft-start” procedures at night or during periods of poor daytime visibility, as well as continuously

during survey operations if surveying is undertaken in December and January;

• Monitor marine cetacean activity during night time surveying or during periods of poor daytime

visibility;

• Record species identification, position (latitude/longitude) and distance from the vessel, where

possible;


and

• Request the temporary termination of the seismic survey, as appropriate.

All data recorded by the MMO and PAM operator should form part of the survey “close-out” report.

6.2.4 OTHER MITIGATION MEASURES

Other mitigation measures that should also be implemented during the survey in order to ensure that any

potential impacts are minimised are listed below.




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6.2.4.2 Equipment

‘Turtle-friendly’ tail buoys should be used by the survey contractor or existing tail buoys should be fitted with

either exclusion or deflector 'turtle guards'.

6.2.4.3 Vessel safety

• The survey vessel must be certified for seaworthiness through an appropriate internationally

recognised marine certification programme (e.g. Lloyds Register, Det Norske Veritas).

The certification, as well as existing safety standards, requires that safety precautions would be taken

to minimise the possibility of an offshore accident;



> A support / chase vessel with an on-board FLO familiar with the fisheries expected in the area;

> The existence of an internationally agreed 500 m safety zone around the survey vessel;

> Cautionary notices to mariners; and

> Access to current weather service information.






• Report any emergency situation to the Commissioner for Petroleum Affairs;

6.2.4.4 Vessel lighting

Lighting on-board survey vessels should be reduced to the minimum safety levels to minimise stranding of

pelagic seabirds on the survey vessels at night. All stranded seabirds must be retrieved and released during

daylight hours;

6.2.4.5 Emissions, discharges into the sea and solid waste

• Ensure adequate maintenance of diesel motors and generators to minimise the volume of soot and

unburned diesel released to the atmosphere;

• Route deck and machinery space drainage to a separate drainage system (oily water catchment

system) for treatment to ensure compliance with MARPOL (15 ppm);

• Ensure all process areas are bunded to ensure drainage water flows into the closed drainage system;

• Use drip trays to collect run-off from equipment that is not contained within a bunded area and route

contents to the closed drainage system;

• Use of low toxicity, biodegradable detergents during deck cleaning to further minimise the potential

impact of deck drainage on the marine environment;

• Ensure adequate maintenance of all hydraulic systems and frequent inspection of hydraulic hoses;

• Undertake spill management training and awareness of crew members of the need for thorough clean-

up of any spillages immediately after they occur, as this would minimise the volume of contaminants

washing off decks;

• Effluent discharge (e.g. sewage and galley waste as per MARPOL requirements) into the sea should

occur as far as possible from the coast;





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• Ensure on-board solid waste storage is secure;

• Ensure that waste (solid and hazardous) disposal onshore is carried out in accordance with the

appropriate laws and ordinances;

• Prepare a project specific Emergency Response Plan and Shipboard Oil Pollution Emergency Plan for

the proposed seismic survey, which defines the organisational structure and protocols that would be

implemented to respond to any incident (including accidental oil / fuel spills) in a safe, rapid, effective

and efficient manner. These plans should be submitted to MME for information purposes as part of

their formal notification prior to survey commencement;
















NAMPORT and the Commissioner for Petroleum Affairs;

6.2.4.6 Communication with key stakeholders

• Prior to survey commencement the operator should consult with the MFMR to discuss their respective

survey programmes (seismic and fisheries research) and negotiate the timing thereof in order to

minimise or avoid disruptions to both parties;



proposed activities) and the likely implications thereof (500 m safety zone and proposed safe

operational limits):





- Midwater Trawling Association of Namibia;




> Other:

- MME

- MET;

- MFMR;

- Directorate of Maritime Affairs;

- Monitoring, Control and Surveillance Unit in Walvis Bay (Vessel Monitoring System in

particular);




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- Namibian Ports Authority;

- Port captains;

- South African Navy Hydrographic office; and

- Overlapping and neighbouring prospecting / exploration right holders.

• The operator must formally notify the MME (Commissioner for Petroleum Affairs2)

of the survey

location, commencement date and anticipated duration of the seismic survey prior to commencement;

• The operator must request, in writing, that the South African Navy Hydrographic office release a Radio

Navigation Warning for the duration of the seismic survey period and that daily notifications be issued

by Walvis Bay Radio. The notifications should give notice of (1) the co-ordinates of the proposed

survey area, (2) an indication of the proposed survey timeframes and day-to-day location of the survey

vessel(s), and (3) an indication of the 500 m safety zones and the proposed safe operational limits of

the survey vessel(s);

• An independent on-board FLO, who is familiar with fishery operations in the area, must be appointed

for the duration of the survey. The duties of the FLO would be to:






activities; and



and progress.

• Ongoing notification is to be undertaken throughout the duration of survey with the submission of daily

reports (via email) indicating the vessel’s location to key stakeholders, as appropriate;

• Surveying should avoid diamond mining vessels, unless prior arrangements have been made with the

operator; and


made available, if requested, to the MFMR, MME, NAMCOR and the Namibian Dolphin Project to

inform studies of cetacean distribution and timing off the Namibian coast.

6.2.4.7 Helicopter operations




• Extensive coastal flights (parallel to the coast within 1 nautical mile of the shore) should be avoided;

and


2 The Commissioner is obliged to notify all relevant parties and cause such offshore location to be published in a “Notice to Mariners” (in

terms of Regulation 15(b) of the Petroleum (Exploration and Production) Act No. 2 of 1991), as published by the South African Navy

Hydrographic office in Cape Town.




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7 ENVIRONMENTAL MANAGEMENT PLAN

This chapter lists the specific environmental protection activities and procedures required to avoid or

minimise impacts on the environment from the proposed seismic survey programme.

The specific environmental protection activities and procedures are addressed under each of the project life

cycle phases listed below:

7.1 PLANNING PHASE

7.1.1 Survey timing

7.1.2 Survey equipment

7.1.3 Survey personnel

7.1.4 Preparation of subsidiary plans

7.1.5 Stakeholder consultation and notification

7.1.6 Approval of EIA

7.2 ESTABLISHMENT PHASE

7.2.1 Compliance with the EMP

7.2.2 Environmental Awareness Training

7.2.3 Notifying other users of the sea

7.3 OPERATIONAL PHASE

7.3.1 Adherence to the EMP

7.3.2 Communication with other users of the sea and

resource managers

7.3.3 Prevention of emergencies

7.3.4 Dealing with emergencies including major oil spills

7.3.5 Pollution control and waste management

7.3.6 Equipment loss

7.3.7 Use of helicopters

7.3.8 Bunkering / refuelling at sea

7.3.9 Seismic survey procedure and monitoring

7.4 DECOMMISSIONING AND CLOSURE PHASE

7.4.1 Survey vessels to leave area

7.4.2 Inform key stakeholders of survey completion

7.4.3 Final waste disposal

7.4.4 Information sharing

7.4.5 Compile seismic survey “close-out” reports




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7.1 PLANNING PHASE

PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:

AUDITABLE MANAGEMENT ACTIONS TO BE TAKEN TO MEET

THE ENVIRONMENTAL OBJECTIVES: ��

RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.1.1 SURVEY

TIMING

Minimise impact on

cetaceans

The seismic survey programme should be undertaken over two seasons

in order to avoid the key cetacean migration and breeding period which

extends from the beginning of June to the end of November (i.e. the

survey period is from December to May).

Surveying during the December / January period requires the

continuous implementation of Passive Acoustic Monitoring (PAM)

technology, in combination with thermal imaging cameras, during

survey operations (see Section 7.1.2).

Spectrum Prior to

finalisation of

survey schedule

/ timing

MMO close-out

report

Minimise impact on

fishing and research

Engage with the fishing industry (specifically the midwater trawl, large

pelagic long-line and dee-sea crab sectors) and MFMR (fisheries

research managers) well in advance of commencement to discuss their

respective fishing and research survey programmes (timing and

location) in order to minimise or avoid disruptions to all parties. The

possibility of undertaking concurrent activities within the seismic survey

area should be investigated.

Spectrum Prior to

finalisation of

survey

programme

Provide copies of

all

correspondence

/ meetings

7.1.2 SURVEY

EQUIPMENT

Minimise impact on

cetaceans and turtles

PAM technology must be implemented when surveying at night or

during adverse weather conditions and thick fog. If surveying is to be

undertaken at night or during poor daytime visibility, the survey vessel

must be fitted with PAM technology.

In addition, PAM technology must be implemented continuously during

survey operations if surveying is undertaken in December and January.

Spectrum

and Seismic

Contractor

Prior to

commencement

of operation

PAM operator

close-out report

For surveying in the December / January period, survey vessels should

be fitted with thermal imaging cameras, which offers observations

possibilities at night, improved detection during daylight hours and

allows precise measurement of the distance of the marine mammal

from the seismic vessel.

MMO record of

inspection

MMO close-out

report

Use ‘turtle-friendly’ tail buoys. Alternatively, the existing tail buoys

should be fitted with either exclusion or deflector 'turtle guards' to

prevent turtle entrapment.

MMO record of

inspection

MMO close-out

report




EIA Report

October 2017

7.1 PLANNING PHASE

PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.1.3 SURVEY

PERSONNEL

Minimise impact on

cetaceans

Appoint an independent on-board Marine Mammal Observer (MMO)

and PAM operator for the duration of the survey. The MMO and PAM

operator must have experience in seabird, turtle and marine mammal

identification and observation techniques.

Spectrum Prior to

commencement

of operation

MMO and, if

necessary, PAM

operator close-

out reports

Minimise impact on

other users of the sea

Appoint an independent on-board Fisheries Liaison Officer (FLO).

The FLO must be familiar with fisheries operating in the area.

FLO close-out

report

7.1.4

PREPARATION OF

SUBSIDIARY

PLANS

Preparation for any

emergency that could

result in an

environmental impact

Ensure the following plans are prepared and in place:

• Emergency Response Plan (including MEDIVAC plan);

• Support vessel and helicopter Emergency Response Plans;

• Shipboard Oil Pollution Emergency Plan (SOPEP) as required by

MARPOL. Note: In case of a major oil spill, emergency responses

and/or Oil Pollution Emergency Plan(s) should refer to the

Namibian National Oil Spill Contingency Plan (NOSCP); and

• Waste Management Plan (see contents in Section 7.3.5).

Spectrum

and Seismic

Contractor

Prior to

commencement

of operation

Confirm

compliance and

justify any

omissions

7.1.5

STAKEHOLDER

CONSULTATION

AND NOTIFICATION

MME notification Compile a Survey Notification document with the specific details of the

survey and submit to the Commissioner for Petroleum Affairs, Ministry

of Mines and Energy (MME). The notification should provide details on

the following:

• Survey lines / area;

• Survey timing and duration;

• Contractor details;

• Vessel specifications (including relevant certification and

insurance);

• Emergency Response Plan;

• Shipboard Oil Pollution Emergency Plan (SOPEP); and

• Details of MMO, PAM operator and FLO.

Spectrum 30-days prior to

commencement

of operations or

as required by

MME

Confirm that

notification was

sent to MME




EIA Report

October 2017

7.1 PLANNING PHASE

PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.1.5 CONT. Stakeholder

notification

• Notify relevant government departments and other key

stakeholders of the proposed survey activities (including

navigational co-ordinates of the survey area, and timing and

duration of survey activities) and the likely implications thereof

(500 m safety zone and proposed safe operational limits).

• The notification must also invite stakeholders to be included on

the daily report distribution list (only those included on the daily

notification database will receive further notification during the

survey).

• Stakeholders include:





- Midwater Trawling Association of Namibia




> MME (Commissioner for Petroleum Affairs);

> Ministry of Environment and Tourism (MET);

> MFMR;

> Directorate of Maritime Affairs;

> Namibian Ports Authority;

> Port captains;

> Monitoring, Control and Surveillance Unit in Walvis Bay

(Vessel Monitoring System in particular); and

> Overlapping and neighbouring prospecting / exploration

right holders.

14 days prior to

commencement

of operations

Provide copies of

all

correspondence

7.1.6 APPROVAL

OF EIA

Compliance with

legislative

requirements

Ensure that Environmental Clearance has been received from MME. Spectrum Prior to

commencement

of operations

Provide copy of

approval letter




EIA Report

October 2017

7.2 ESTABLISHMENT PHASE

PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.2.1 COMPLIANCE

WITH EMP

Operator and

contractor to commit

to adherence to

environmental

protection activities

and procedures

• Verify that a copy of the approved EIA is supplied to all Contractors

and is on-board the survey and support vessels during the

operation.

• Operator to commit organisation and Contractor to meet the

requirements of the EMP.

• Verify that procedures and systems for compliance are in place.

• Verify that correct equipment and personnel are available to meet

the requirements of the EMP.

Spectrum

and Seismic

Contractor

Audit

Minutes of

meetings

Prior to

commencement

of operation

Ensure that a

copy of the EIA

is provided to the

Seismic

Contractor and

that an

acknowledgment

of receipt form is

signed

7.2.2

ENVIRONMENTAL

AWARENESS

TRAINING

Ensure personnel are

appropriated trained

• Undertake Environmental Awareness Training to ensure the

vessel’s personnel are appropriately informed of the purpose and

requirements of the EMP.

• Verify that responsibilities are allocated to personnel.

Spectrum

and Seismic

Contractor

Training records Copy of

attendance

register

7.2.3 NOTIFYING

OTHER USERS OF

THE SEA

Ensure that other

users are aware of the

seismic survey

• Request, in writing, that the South African Navy Hydrographic

office release a Radio Navigation Warnings for the duration of the

seismic survey period and that daily notifications be issued by

Walvis Bay Radio.

• Distribute a Notice to Mariners directly to fishing operators through

recognised fishing associations and directly to fishing vessels. The

Notice to Mariners should give notice of (1) the co-ordinates of the

proposed survey area, (2) an indication of the proposed survey

timeframes, and (3) an indication of the proposed safe operational

limits of the survey vessel.

Spectrum,

Seismic

Contractor

and FLO

Copy of notices

sent

Notice to

mariners to be

issued 24 hours

prior to start

Confirm that

notices were

sent to relevant

parties

Provide copies of

notices and list

of those to whom

it was sent




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.3.1 ADHERENCE

TO THE EMP

Operate in an

environmentally

responsible manner

• Comply fully with the EMP (compliance would mean that all

activities were undertaken successfully and details recorded);

• Subscribe to the principles of an internationally acceptable

Environmental Management System on-board the vessels. This

includes environmental awareness training, waste management

and environmental monitoring, record keeping and continuous

improvement; and

• Comply with the “Environmental Guidelines for Worldwide

Geophysical Operations” issued by the International Association of

Geophysical Contractors (IAGC).

Seismic

Contractor

Self-audits Throughout

programme

Copies of self-

audit reports

7.3.2

COMMUNICATION

WITH OTHER

USERS OF THE

SEA AND

RESOURCE

MANAGERS

Promote cooperation

and successful

multiple use of the

sea, including

promotion of safe

navigation

Daily reports shall be submitted, via email, to key stakeholders and

those stakeholders that request to be notified during the survey (see

Section 7.1.5). Daily reports should include, but not limited to, the

following:

• Survey details (incl. survey programme / forecast, percentage

completion & start-up procedure);

• Vessel interaction;

• Meteorological Conditions;

• Observation times and sightings;

• Waste management; and

• Survey strategy (incl. survey progress and next line to be

acquired).

MMO / FLO Copies of written

notices and

correspondence

During

operations as

required

Provide copies of

written notices

and list of those

to whom it was

sent

Keep constant watch for approaching vessels during operations. Warn

by radio and chase boat if required. The duties of the FLO include:

• Identifying fishing vessels active in the area and associated gear;

• Advising on actions to be taken in the event of encountering fishing

gear;

• Providing back-up on-board facilitation with the fishing industry and

other users of the sea; and

• Daily electronic reporting on vessel activity and recording of any

communication and/or interaction.

Officer on

watch / FLO

Throughout

operation




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

Support vessel to enforce the 500 m safety zone in order to minimise

the risk of fishing vessels or gear from being entangled with or damaged

by the streamers or survey vessels.

Seismic

Contractor /

FLO

Records of

encounters with

fishing boats

7.3.3 PREVENTION

OF EMERGENCIES

Minimise disruption to

other legitimate users

of the sea by

respecting their rights

and the chance of

emergency occurring

and subsequent

damage to the

environment

• Co-operate with other legitimate users of the sea to minimise

disruption to other marine activities.

• Vessels are required to fly standard flags, lights (three all-round

lights in a vertical line, with the highest and lowest lights being red

and the middle light being white) or shapes (three shapes in a

vertical line, with the highest and lowest lights being balls and the

middle light being a diamond) to indicate that the seismic vessel is

engaged in towing surveys and is restricted in manoeuvrability.

• Use warning lights during twilight and at night and in periods of low

visibility.

• Maintain standard visual watch procedures (also see

Section 7.3.2).

• Maintain 500 m safety zone around survey vessel through a Notice

to Mariners and Coastal Navigation Warning.

• 24 hr chase boat on patrol during seismic surveying.

• Radio communication to alert approaching vessels.

• Use flares or fog horn where necessary.

• Practice weekly emergency response drills.

• Establish lines of communication with the following emergency

response agencies/facilities: MET; MFMR; Ministry of Works,

Transport and Communications; Sea Rescue Institute of Namibia;

and Port Captain(s).

Seismic

Contractor /

FLO

Throughout

operation

Record any

incidents outside

of normal

occurrence




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.3.4 DEALING

WITH

EMERGENCIES

INCLUDING MAJOR

OIL SPILLS (owing

to collision, vessel

break-up, refuelling

etc.)

Minimise damage to

the environment by

implementing

response procedures

efficiently

• Adhere to obligations regarding other vessels in distress.

• Implement emergency plans in Section 7.1.4.

• Report any emergency situation to the Commissioner for

Petroleum Affairs.

• Support vessels must have the necessary spill response capability

to deal with accidental spills in a safe, rapid, effective and efficient

manner.

• In the event of an oil spill that poses a risk of major harm to the

environment immediately notify NAMPORT and the Commissioner

for Petroleum Affairs.

• Information that should be supplied when reporting a spill includes:

> The type and circumstances of incident, ship type, port of

registry, nearest agent representing the ships company;

> Geographic location of the incident, distance off-shore and

extent of oil spill;

> Prevailing weather conditions, sea state in affected area

(wind direction and speed, weather and swell); and

> Persons and authorities already informed of the spill.

• Where diesel, which evaporates relatively quickly, has been

spilled, the water should be agitated or mixed using a propeller

boat/dinghy to aid dispersal and evaporation.

• Dispersants should not be used without authorisation of MFMR.

• Dispersants should not be used:

> On diesel or light fuel oil;

> On heavy fuel oil;

> On slicks > 0.5 cm thick;

> On any oil spills within 5 nautical miles off-shore or in depths

less than 30 metres; and

> In areas far offshore where there is little likelihood of oil

reaching the shore.

• Dispersants are most effective:

> On fresh crude oils; under turbulent sea conditions (as

effective use of dispersants requires mixing); and

Spectrum

and Seismic

Contractor

Audits, Ships

log, Record of

Notifications

In the event of

accident / spill

Record of all

spills (Spill

Record Book),

including spill

reports;

emergency

exercises and

audit records.

Incident log




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

> When applied within 12 hours or at a maximum of 24 hours.

• The volume of dispersant application should not exceed 20-30% of

the oil volume.

7.3.5 POLLUTION

CONTROL AND

WASTE

MANAGEMENT of

products disposed

of: into the air

(exhausts, cfcs and

incinerators), to sea

(sewage, food, oils),

to land (used oils

etc., metals,

plastics, glass, etc.)

Minimise pollution and

maximise recycling by

implementing and

maintain pollution

control and waste

management

procedures at all times

• Implement Waste Management Plan (see Section 7.1.4).

The plan must comply with legal requirements for waste

management and pollution control (for air and water quality levels

at sea) and ensure "good housekeeping" and monitoring practices:

> General waste:

- Initiate a waste minimisation system.

- No disposal overboard.

- Ensure on-board solid waste storage is secure.

- Incinerate (non-hazardous) or transport ashore for

disposal. Retain waste receipts.

> Galley (food) waste:

- No disposal within 3 nm of the coast.

- Disposal between 3 nm and 12 nm needs to be

comminuted to particle sizes smaller than 25 mm.

- Disposal beyond 12 nm requires no treatment.

> Deck drainage:

- Deck drainage should be collected in oily water

separator systems.

- Ensure that weather decks are kept free of spillage.

- Mop up any spills immediately with biodegradable low

toxicity detergents.

- Low-toxicity biodegradable detergents should be used

in cleaning of all deck spillage.

- Ensure compliance with MARPOL standards.

> Machinery space drainage:

- Vessels must comply with international agreed

standards regulated under MARPOL.

- Ensure all process areas are bunded to ensure

drainage water flows into the closed drainage system.

- Use drip trays to collect run-off from equipment that is

not contained within a bunded area and route contents

Seismic

Contractor

Audits

Registers

Record Books

Daily Reports

Throughout

operation

Provide

summary of

waste record

book / schedule

and receipts.

Manifest

required for all

shipments to

shore.

Report

occurrence of

minor oil spills

and destination

of wastes




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

to the closed drainage system

- All machinery space drainage would pass through an

oil/water filter to reduce the oil in water concentration

to less than 15 mg/l.

> Sewage:

- Use approved treatment plants that comply with

MARPOL standards.

- No disposal within4 nm of the coast.

- Disposal between 4 nm and 12 nm needs to be

comminuted and disinfected prior to disposal into the

sea.

- Disposal beyond 12 nm requires no treatment.

> Medical waste: Seal in aseptic containers for appropriate

disposal onshore.

> Metal: Send to shore for recycling or disposal.

> Other waste: Incinerate (only non-hazardous waste) or send

remaining waste to a licensed waste site. Ensure waste

disposal is carried out in accordance with appropriate laws

and ordinances.

> Waste oil: Return used oil to a port with a registered facility

for processing or disposal.

> Wastewater: Comply with MARPOL.

> Minor oil spill: Use oil absorbent.

> Emissions to the atmosphere: Properly tune and maintain all

engines, motors, generators and all auxiliary power to

contain the minimum of soot and unburned diesel.

> Other hazardous waste: Send to designated onshore

hazardous disposal site.

• Ensure all crew is trained in spill management.




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.3.6 EQUIPMENT

LOSS

Minimise hazards left

on the sea bed or

floating in the water

column, and inform

relevant parties

• Keep a record of lost equipment and all items lost overboard and

not recovered.

• When any item that constitute a seafloor or navigation hazard is

lost on the sea bed, or in the sea, a standard form must be

completed which records the date and cause of loss, details of

equipment type, vessel Sea Control location, sea state and

weather, and the nature of the sea bed.

• Pass information to the South African Navy Hydrographic office,

MME, the MFMR, relevant mining companies and fishing

associations.

Seismic

Contractor

Incident records Throughout

operation, in the

event of an

incident

Provide a list of

lost equipment

and a copy of

record sheet

7.3.7 USE OF

HELICOPTERS for

crew changes,

servicing, etc.

Minimise disturbance /

damage to marine and

coastal fauna

• All flight paths should be planned to avoid by at least 1 852 m

(i.e. 1 nm) all seal colonies between Walvis Bay and the survey

area (including Cape Cross, Möwe Bay and Cape Frio) and

seabird colonies in Walvis Bay, Swakopmund and Cape Cross, as

well as the Kunene River mouth and estuary.

• Extensive coastal flights (parallel to the coast within 1 nm of the

shore) should also be avoided.

• All pilots must be briefed on ecological risks associated with over

flights of seabird and seal colonies.

• Helicopter logs shall be kept to demonstrate compliance with set

flight paths. Report any deviations from set flight plans.

Spectrum

and

Helicopter

contractor

As required Submit copy of

set flight path

Copies of reports

on deviations

from set flight

paths

7.3.8 BUNKERING /

REFUELLING AT

SEA

Minimise damage to

marine and coastal

fauna

• An application for the transfer of oil at sea (outside a harbour) must

be submitted to the Minister, via the Permanent Secretary, at least

two weeks before the proposed date of transfer.

• Not less than 24 hours prior to the commencement of the transfer

operation the Permanent Secretary must be informed, in writing,

that the ship is, and will be kept, in a fit state to undertake the

transfer operation and to contend with any emergency that may

arise.

• Offshore bunkering should not be undertaken in the following

circumstances:

> Wind force and sea state conditions of 6 or above on the

Beaufort Wind Scale;

Seismic

Contractor

Provide copies of

the

correspondence

with the

Permanent

Secretary




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:





• Ensure support vessels have the necessary spill response

capability to deal with accidental spills in a safe, rapid, effective

and efficient manner.

7.3.9 SEISMIC

SURVEY

PROCEDURE AND

MONITORING

Reduce disturbance of

marine life, particularly

cetaceans (whales

and dolphins), seals,

turtles and seabirds

(particularly penguins)

An on-board MMO and PAM operator shall be assigned to perform

marine mammal observations and notifications (see Section 7.1.3).

Spectrum

and Seismic

Contractor

MMO & PAM

operator close-

out report

Ensure the lowest practicable seismic source array volume to achieve

the geophysical objective is defined and used throughout the survey

period.

Spectrum Prior to survey

operations

Pre-survey watch:

• Undertake a 30-minute pre-survey watch (prior to soft-starts) in

order to confirm there is no diving seabird (specifically large flocks

consisting of several hundred birds), seal, turtle or cetacean

activity within 500 m of the seismic source array. The pre-watch

survey methodology differs depending on when the survey is

undertaken:

> Dec to end Jan: visually and using PAM technology during

the day and PAM and Infra-red technology at night or during

periods of poor daytime visibility; and

> Feb to end May: visually during the day and using PAM

technology at night or during periods of poor daytime

visibility).

• In the case of seals and small cetaceans (< 3 m in overall length),

which are often attracted to survey vessels, the normal “soft-start”

procedures should be allowed to commence, if after a period of 30

minutes seals and small cetaceans are still within 500 m of the

airguns.

MMO/ PAM

operator

Records of pre-

watches

Prior to “soft-

start”

procedures

MMO & PAM

operator close-

out report




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

“Soft-start” procedure:

• All initiations of seismic surveys must be carried out as “soft-starts”

for a minimum of 20 minutes. This requires that the sound source

be ramped from low to full power rather than initiated at full power,

thus allowing a flight response by marine fauna to outside the zone

of injury or avoidance.

• Where possible, “soft-starts” should be planned so that they

commence within daylight hours.

Seismic

Contractor

Records of “soft-

start” procedures

Prior to

surveying at full

power

MMO & PAM

operator close-

out report

Break in seismic acquisition:

• All breaks in seismic acquisition of longer than 20 minutes must be

followed by the pre-shoot watch and a “soft-start” procedure of at

least 20 minutes prior to the survey operation continuing.

• Breaks shorter than 20 minutes should be followed by a visual

scan for marine mammals within the 500 m mitigation zone (not a

pre-shoot watch) and a “soft-start”, of similar duration.

Seismic

Contractor

Records of pre-

watches and

“soft-start”

procedures

After breaks in

seismic

acquisition

MMO & PAM

operator close-

out report

Monitoring:

• MMO is to monitor survey operations visually during the day.

Duties include:

> Monitoring marine faunal activity during daytime surveying;

> Confirm that there is no marine faunal activity within

500 m of the seismic source array prior to commencing with

the “soft-start” procedures;

> Observing and recording responses of marine fauna to the

seismic surveys, including incidence and behaviour, and any

mortality as a result of the surveys. Data capture should

include species identification, position (latitude/longitude),

distance from the vessel, swimming speed and direction (if

applicable) and any obvious changes in behaviour (e.g.

startle responses or changes in surfacing/diving frequencies,

breathing patterns) as a result of the survey activities;

> Recording survey activities, including sound levels, “soft-

start” procedures and survey periods (duration);

MMO/ PAM

operator

Records of

marine fauna

observations and

“soft-start”

procedures

Throughout

survey

operations

MMO & PAM

operator close-

out report




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

> Requesting the temporary termination of seismic acquisition,

as appropriate;

> Recording meteorological conditions;

> Monitoring compliance with international marine pollution

regulations (MARPOL 73/78 standards); and

> Preparing daily reports of all observations.

• PAM operator is monitor at night and during periods of poor

visibility. Duties include:

> Monitoring marine cetacean activity during:

- night time surveying or during periods of poor visibility;

and

- continually if surveying in December and January.

> Confirming that there is no marine mammal activity within

500 m of the seismic source array prior to commencing with

the “soft-start” procedures at night or during periods of poor

daytime visibility;

> Recording species identification, position (latitude/longitude)

and distance from the vessel, where possible;

> Recording survey activities, including sound levels, “soft-

start” procedures and survey periods (duration); and

> Requesting the temporary termination of seismic acquisition,

as appropriate.

Temporary termination of seismic acquisition:

• During surveying the sound source should be terminated when:

> obvious negative changes to turtle, seal and cetacean

behaviour is observed;

> turtles or cetaceans are observed within 500 m of the active

sound source and appear to be approaching the sound

source; or

> there is visual evidence of mass mortality of fish or mortality /

injuries to seabirds, turtles or cetaceans as a direct result of

the seismic survey.

• The survey should be terminated until such time that the MMO /

PAM operator confirms that:

> Turtles or cetaceans have moved to a point that is more than

Seismic

Contractor

and MMO /

PAM

operator

Termination log Throughout

survey

operations

MMO & PAM

operator close-

out report




EIA Report

October 2017


PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

500 m from the sound source;

> Despite continuous observation, 30 minutes has elapsed

since the last sighting of the turtles or cetaceans within

500 m of the sound source; and

> Risks to seabirds, turtles, seals or cetaceans have been

significantly reduced.

• A log of all termination decisions must be kept.




EIA Report

October 2017

7.4 DECOMMISSIONING AND CLOSURE PHASE

PROJECT PHASE

AND ACTIVITIES:

ENVIRONMENTAL

OBJECTIVES:



RESPONSI-

BILITY:

CONTROL

MEASURES: TIMING:

REQUIREMENT

FOR “CLOSE-

OUT” REPORT:

7.4.1 SURVEY

VESSELS TO

LEAVE AREA

Leave survey area as

it was prior to survey

Ensure that all deployed equipment is retrieved. Seismic

Contractor

On completion

of survey

MMO close-out

report

7.4.2 INFORM KEY

STAKEHOLDERS

OF SURVEY

COMPLETION

Ensure that relevant

parties are aware that

the seismic campaign

is complete

Inform the MME and other key stakeholders (see Section 7.1.5) of the

survey completion.

Spectrum Within two

weeks after

completion of

survey

Copies of

notification

documentation

required.

7.4.3 FINAL WASTE

DISPOSAL

Minimise pollution and

ensure correct

disposal of waste

Dispose all waste retained on-board at a licensed waste site using a

licensed waste disposal contractor.

Seismic

Contractor

Waste receipts When vessel is

in port

Receipt required

from contractor

7.4.4 INFORMATION

SHARING

Information sharing Take steps to share data collected during the survey (e.g. marine

mammal incidence and behaviour), if requested, to resource managers

(including MFMR, MET, NAMCOR and appropriate research institutes).

Spectrum As requested

7.4.5 COMPILE

SEISMIC SURVEY

“CLOSE-OUT”

REPORTS

Ensure corrective

action and compliance

and contribute towards

improvement of EMP

implementation

• Compile a “close-out” report at the end of the seismic survey.

• The “close-out” report must be based on requirements of the

monitoring and EMP.

• Provide information / records as indicated in the “close-out” report

column of the EMP within 90 days of the end of the survey.

• Provide a copy of the report to the MME.

Spectrum Within 90 days

of survey

completion




EIA Report

October 2017

8 REFERENCES

ATKINSON, L.J. 2009. Effects of demersal trawling on marine infaunal, epifaunal and fish assemblages:

studies in the southern Benguela and Oslofjord. PhD Thesis. University of Cape Town, pp 141

ATTWOOD, C. 2014. Making a lot of noise about the potential blue economy. Through the fish eye lens. A

wide-angle perspective on commercial fishing. Maritime Review Africa: November / December 2014.

BAILEY, G.W. 1991. Organic carbon flux and development of oxygen deficiency on the modern Benguela

continental shelf south of 22°S: spatial and temporal variability. In: TYSON, R.V., PEARSON, T.H.

(Eds.), Modern and Ancient Continental Shelf Anoxia. Geol. Soc. Spec. Publ., 58: 171–183.

BAILEY, G.W. 1999. Severe hypoxia and its effect on marine resources in the southern Benguela upwelling

system. Abstract, International Workshop on Monitoring of Anaerobic processes in the Benguela

Current Ecosystem off Namibia.

BAILEY, G.W, DE, C.J. BEYERS, B. & LIPSCHITZ, S.R. 1985. Seasonal variation in oxygen deficiency in

waters off South West Africa in 1975 and 1976 and its relation to the catchability and distribution of

the Cape rock lobster Jasus lalandii. South African Journal of Marine Science 3: 197-214.

BAILEY G.W. & CHAPMAN, P. 1991. Chemical and physical oceanography. In: Short-term variability during

an Anchor Station Study in the southern Benguela Upwelling system. Prog. Oceanogr., 28: 9-37.

BAKUN A. & WEEKS, S.J. 2006. Adverse feedback sequences in exploited marine ecosystems: are

deliberate interruptive actions warranted? Fish and Fisheries 7: 316-333

BANKS, A. BEST, P.B., GULLAN, A., GUISSAMULO, A., COCKCROFT, V. & FINDLAY, K. 2011. Recent

sightings of southern right whales in Mozambique. Document SC/S11/RW17 submitted to IWC

Southern Right Whale Assessment Workshop, Buenos Aires 13-16 Sept. 2011

BARENDSE, J. 2011. Local movements, migrations and habitat use of humpback whales off the west coast

of South Africa, including observations of southern right whales. In: Zoology and Entomology

(University of Pretoria, Pretoria).

BARENDSE, J., BEST, P.B., THOMTON, M., POMILLA, C. CARVALHO, I. & ROSENBAUM, H.C. 2010.

Migration redefined? Seasonality, movements and group composition of humpback whales

Megaptera novaeangliae off the west coast of South Africa. Afr. J. mar. Sci., 32(1): 1-22.

BARENDSE, J., BEST, P.B., THORNTON, M., ELWEN, S.H., ROSENBAUM, H.C., CARVALHO, I.,

POMILLA, C., COLLINS, T.J.Q. & M.A. MEŸER, 2011. Transit station or destination? Attendance

patterns, regional movement, and population estimate of humpback whales Megaptera novaeangliae

off West South Africa based on photographic and genotypic matching. African Journal of Marine

Science, 33(3): 353-373.

BARGER, J.E. & W.R. HAMBLEN. 1980. “The air gun impulsive underwater transducer”. J. Acoust. Soc.

Am., 68(4): 1038-1045.

BARNARD, P. 1998. Biological diversity in Namibia - a country study. Namibian National Biodiversity Task

Force, Windhoek.

BERG, J.A. & R.I.E. NEWELL, 1986. Temporal and spatial variations in the composition of seston available

to the suspension-feeder Crassostrea virginica. Estuar. Coast. Shelf. Sci., 23: 375–386.

BEST, P,B. (1994). A review of the catch statistics for modern whaling in Southern Africa, 1908–1930.

Reports to the International Whaling Commission 44: 467–485.

BEST, P.B. 2001. Distribution and population separation of Bryde’s whale Balaenoptera edeni off southern

Africa. Mar. Ecol. Prog. Ser., 220: 277 – 289.

BEST, P.B. 2007. Whales and Dolphins of the Southern African Subregion. Cambridge University Press,

Cape Town, South Africa.

BEST, P.B. & ALLISON, C. 2010. Catch History, seasonal and temporal trends in the migration of humpback

whales along the west coast of southern Africa. IWC sc/62/SH5.




EIA Report

October 2017

BEST, P.B. & LOCKYER, C.H. 2002. Reproduction, growth and migrations of sei whales Balaenoptera

borealis off the west coast of South Africa in the 1960s. South African Journal of Marine Science, 24:

111-133.

BEYERS, C.J. DE B., C.G. WILKE & GOOSEN, P.C. 1994. The effects of oxygen deficiency on growth,

intermoult period, mortality and ingestion rates of aquarium-held juvenile rock lobster Jasus lalandii.

S. Afr. J. Mar. Sci., 14: 79-88.

BIANCHI, G., HAMUKUAYA, H. & ALVHEIM, O. 2001. On the dynamics of demersal fish assemblages off

Namibia in the 1990s. South African Journal of Marine Science 23: 419-428.

BIANCHI, G., CARPENTER, K.E., ROUX, J.-P., MOLLOY, F.J., BOYER, D. & BOYER, H.J. 1999. FAO

species identification guide for fishery purposes. Field guide to the Living Marine Resources of

Namibia, 256 pp.

BICKERTON, I.B. & CARTER, R.A. 1995. Benthic Macrofauna Distributions on the Inner Continental Shelf

off Lüderitz. In: CSIR (1995). Environmental Impact Assessment for the proposed mining of

Concession Area M46/3/1607 off Lüderitz Bay: Namibia. CSIR Report EMAS-C95040b,

Stellenbosch, South Africa.

BOYD, A..J. & G.P.J. OBERHOLSTER, 1994. Currents off the west and south coasts of South Africa. S.

Afr. Shipping News and Fish. Ind. Rev., 49: 26-28.

BOYER, D. & BOYER, H. (in press). Albatrosses, White-chinned Petrel and Northern Giant-Petrel. In:

Simmons RE, Brown CJ. Birds to watch in Namibia: red, rare and endemic species. National

Biodiversity Programme, Windhoek, Namibia

BRANCH, T.A., STAFFORD, K.M., PALACIOS, D.M., ALLISON, C., BANNISTER, J.L., BURTON, C.L.K.,

CABRERA, E., CARLSON, C.A., GALLETTI VERNAZZANI, B., GILL, P.C., HUCKE-GAETE, R.,

JENNER, K.C.S., JENNER, M.-N.M., MATSUOKA, K., MIKHALEV, Y.A., MIYASHITA, T.,

MORRICE, M.G., NISHIWAKI, S., STURROCK, V.J., TORMOSOV, D., ANDERSON, R.C., BAKER,

A.N., BEST, P.B., BORSA, P., BROWNELL JR, R.L., CHILDERHOUSE, S., FINDLAY, K.P.,

GERRODETTE, T., ILANGAKOON, A.D., JOERGENSEN, M., KAHN, B., LJUNGBLAD, D.K.,

MAUGHAN, B., MCCAULEY, R.D., MCKAY, S., NORRIS, T.F., OMAN WHALE AND DOLPHIN

RESEARCH GROUP, RANKIN, S., SAMARAN, F., THIELE, D., VAN WAEREBEEK, K. &

WARNEKE, R.M. 2007. Past and present distribution, densities and movements of blue whales in

the Southern Hemisphere and northern Indian Ocean. Mammal Review, 37 (2): 116-175.

BRANDÃO, A., BEST, P.B. & BUTTERWORTH D.S. 2011. Monitoring the recovery of the southern right

whale in South African waters. Paper SC/S11/RW18 submitted to IWC Southern Right Whale

Assessment Workshop, Buenos Aires 13-16 Sept. 2011.

BREEZE, H., DAVIS, D.S. BUTLER, M. & V. KOSTYLEV, 1997. Distrbution and status of deep sea corals

off Nova Scotia. Marine Issues Special Committee Special Publication No. 1. Halifax, NS: Ecology

Action Centre. 58 p.

BRIERLEY A.S., AXELSEN B.E., BUECHER E., SPARKS C.A.J., BOYER H.J. & GIBBONS, M.J. 2001.

Acoustic observations of jellyfish in the Namibian Benguela. Marine Ecology Progress Series 210:

55-66

BRICELJ, V.M. & MALOUF, R.E. 1984. Influence of algal and suspended sediment concentrations on the

feeding physiology of the hard clam Mercenaria mercenaria. Mar. Biol., 84: 155–165.

BROUWER, S.L., MANN, B.Q., LAMBERTH, S.J., SAUER, W.H.H. & C. ERASMUS, 1997. A survey of the

South African shore angling fishery. S. Afr. J. Mar. Sci., 18: 165-178.

BRÜCHERT, V., BARKER JǾRGENSEN, B., NEUMANN, K., RIECHMANN, D., SCHLÖSSER M. &

SCHULZ, H. 2003. Regulation of bacterial sulfate reduction and hydrogen sulfide fluxes in the central

Namibian coastal upwelling zone. Geochim. Cosmochim. Acta, 67(23): 4505-4518.




EIA Report

October 2017

CARVALHO, I., LOO, J., COLLINS, T., POMILLA, C., BEST, P.B., HERSCH, R., LESLIE, M.S., &

ROSENBAUM, H.C. 2010. Temporal patterns of population structure of humpback whales in West

coast of Africa (B stock). Paper SC/62/SH8 Submitted to the Scientific Committee of the

International Whaling Commission. 1–13.

CHAPMAN, P. & SHANNON, L.V. 1985. The Benguela ecosystem Part II. Chemistry and related processes.

pp.183-251 in, Oceanography and marine biology: an annual review, Vol. 23, [ed.M.Barnes] .

Aberdeen: Aberdeen University Press. 644pp.

CHIVERS, S., LEDUC, R., ROBERTSON, K., BARROS, N. & A. DIZON, 2004. Genetic variation of Kogia

spp. With preliminary evidence for two species of Kogia sima. Marine Mammal Science, 21: 619-634.

CHRISTIE, N.D. 1974. Distribution patterns of the benthic fauna along a transect across the continental shelf

off Lamberts Bay, South Africa. Ph.D. Thesis, University of Cape Town, 110 pp & Appendices.

CHRISTIE N.D. & MOLDAN, A.G. 1977. Effects of fish factory effluent on the benthic macro-fauna of

Saldanha Bay. Marine Pollution Bulletin, 8: 41-45.

CLARK, M.R., O’SHEA, S., TRACEY, D. & GLASBY, B. 1999. New Zealand region seamounts. Aspects of

their biology, ecology and fisheries. Report prepared for the Department of Conservation, Wellington,

New Zealand, August 1999. 107 pp.

COCKCROFT, A.C, SCHOEMAN, D.S., PITCHER, G.C., BAILEY, G.W. & VAN ZYL, D.L. 2000. A mass

stranding, or ‘walk out’ of west coast rock lobster, Jasus lalandii, in Elands Bay, South Africa:

Causes, results and implications. In: VON VAUPEL KLEIN, J.C. and F.R. SCHRAM (Eds), The

Biodiversity Crisis and Crustacea: Proceedings of the Fourth International Crustacean Congress,

Published by CRC press.

COETZEE, J.C., VAN DER LINGEN, C.D., HUTCHINGS, L. & FAIRWEATHER, T.P. 2008. Has the fishery

contributed to a major shift in the distribution of South African sardine? ICES Journal of Marine

Science 65: 1676–1688.

COMPAGNO, L.J.V., EBERT, D.A. and COWLEY, P.D. 1991. Distribution of offshore demersal cartilaginous

fish (Class Chondrichthyes) off the West Coast of southern Africa, with notes on their systematics. S.

Afr. J. Mar. Sci. 11: 43-139.

CRAWFORD, R.J.M., SHANNON, L.V. & POLLOCK, D.E. 1987. The Benguela ecosystem. Part IV. The

major fish and invertebrate resources. Oceanogr. Mar. Biol. Ann. Rev. 25: 353-505.

CRUIKSHANK, R.A. 1990. Anchovy distribution off Namibiadeduced from acoustic surveys with an

interpretation of migration by adults and recruits. S. Afr. J. Mar. Sci., 9: 53-68.

CSIR. 1996. Elizabeth Bay monitoring project: 1995 review. CSIR Report ENV/S-96066.

CSIR, 2009. Environmental Impact Assessment for the Proposed Desalination Project at Mile 6 Near

Swakopmund, Namibia, Draft EIR Report. Stellenbosch: CSIR.

CURRIE, H., GROBLER, K. & KEMPER, J. (eds). 2009. Namibian Islands’ Marine Protected Area. Ministry

of Fisheries and Marine Resources, Namibia. http://www.nacoma.org.na/ key_Activities/Marine

Protected Areas.htm.

CURRIE, H., GROBLER, K. & J. KEMPER (NACOMA), 2008. Concept note, background document and

management proposal for the declaration of Marine Protected Areas on and around the Namibian

offshore islands and adjacent coastal areas. Compiled by Feike for the Ministry of Fisheries and

Marine Resources, Namibian Coast Conservation & Management Project and World Wildlife

Fund for Nature. Draft 4: February 2008, pp163.

DAVID, J.H.M, 1989. Seals. In: Oceans of Life off Southern Africa, Eds. Payne, A.I.L. and Crawford, R.J.M.

Vlaeberg Publishers. Halfway House, South Africa.

DE DECKER, A.H., 1970. Notes on an oxygen-depleted subsurface current off the west coast of South

Africa. Invest. Rep. Div. Sea Fish. South Africa, 84, 24 pp.




EIA Report

October 2017

DESPREZ, M. 2000. Physical and biological impact of marine aggregate extraction along the French coast

of the Eastern English Channel: short-and long-term post-dredging restoration. ICES Journal of

Marine Science, 57: 1428–1438.

DRAKE, D.E., CACCHIONE, D.A. & H.A. KARL, 1985. Bottom currents and sediment transport on San

Pedro Shelf, California. J. Sed. Petr., 55: 15-28.

DUNCOMBE-RAE, C.M. 2005. A demonstration of the hydrographic partitioning of the Benguela upwelling

ecosystem at 26º40’ S. African Journal of Marine Science 27: 617-628

EKAU W, & VERHEYE, H.M. 2005. Influence of oceanographic fronts and low oxygen on the distribution of

ichthyoplankton in the Benguela and southern Angola currents. African Journal of Marine Science

27: 629-639

ELLINGSEN, K.E. 2002. Soft-sediment benthic biodiversity on the continental shelf in relation to

environmental variability. Marine Ecology Progress Series, 232: 15-27.

ELWEN, S.H., TONACHELLA, N., BARENDSE, J,. COLLINS, T.J.Q., BEST, P.B., ROSENBAUM, H.C.,

LEENEY, R.H. & GRIDLEY, T. 2014. Humpback whales in Namibia 2005-2012: occurrence,

seasonality and a regional comparison of photographic catalogues and scarring rates with Gabon

and West South Africa. Paper SC/65a/SH24 to the Scientific Committee of the International Whaling

Commission.

ELWEN, S.H., GRIDLEY, T., ROUX, J.-P., BEST, P.B. & SMALE, M.J. 2013. Records of Kogiid whales in

Namibia, including the first record of the dwarf sperm whale (K. sima). Marine Biodiversity Records.

ELWEN, S.H., FINDLAY, K.P., KISZKA J. & WEIR, C.R. 2011. Cetacean research in the southern African

subregion: a review of previous studies and current knowledge. African Journal of Marine Science

33: 469–493.

ELWEN, S.H. & LEENEY, R.H. 2011. Interactions between leatherback turtles and killer whales in Namibian

waters, including predation. South African Journal of Wildlife Research, 41(2): 205-209.

ELWEN, S.H. MEŸER, M.A.M, BEST, P.B., KOTZE, P.G.H, THORNTON, M. and SWANSON, S. 2006.

Range and movements of a nearshore delphinid, Heaviside's dolphin Cephalorhynchus heavisidii a

determined from satellite telemetry. Journal of Mammalogy. 87(5): 866–877.

EMANUEL, B.P., BUSTAMANTE, R.H., BRANCH, G.M., EEKHOUT, S. & F.J. ODENDAAL, 1992. A

zoogeographic and functional approach to the selection of marine reserves on the west coast of

South Africa. S. Afr. J. Mar. Sci., 12: 341-354.

EMEIS, K.-C., BRÜCHERT, V., CURRIE, B., ENDLER, R., FERDELMAN, T., KIESSLING, A., LEIPE, T.,

NOLI-PEARD, K., STRUCK, U. & VOGT, T. 2004. Shallow gas in shelf sediments of the Namibian

coastal upwelling ecosystem. Continental Shelf Research, 24: 627-642.

EMERY, K.O., UCHUPI, E., BOWIN, C.O., PHILLIPS, J. & SIMPSON, E.S.W. 1975. Continental margin off

western Africa: Cape St Francis (South Africa) to Walvis Bay (South-West Africa). Bulletin American

Association Petroleum Geologists, 59: 3-59.

ENVIRONMENTAL EVALUATION UNIT. 1996. Impacts of Deep Sea Diamond Mining, in the Atlantic 1

Mining Licence Area in Namibia, on the Natural Systems of the Marine Environment. Environmental

Evaluation Unit Report No. 11/96/158, University of Cape Town. Prepared for De Beers Marine (Pty)

Ltd. 370 pp.

FINDLAY, K.P., BEST, P.B., ROSS, G.J.B. & COCKCROFT, V.C. 1992. The distribution of small odontocete

cetaceans off the coasts of South Africa and Namibia. South African Journal of Marine Science 12:

237-270.

FLACH, E. & THOMSEN, L. 1998. Do physical and chemical factors structure the macrobenthic community

at a continental slope in the NE Atlantic? Hydrobiologia, 375/376: 265-285.

FOSSING, H., FERDELMAN, T.G. & P. BERG, 2000. Sulfate reduction and methane oxidation in

continental margin sediments influenced by irrigation (South-East Atlantic off Namibia). Geochim.

Cosmochim. Acta. 64(5): 897–910.




EIA Report

October 2017

GOOSEN, A.J.J., GIBBONS, M.J., MCMILLAN, I.K., DALE, D.C. & WICKENS, P.A. 2000. Benthic biological

study of the Marshall Fork and Elephant Basin areas off Lüderitz. Prepared by De Beers Marine

(Pty) Ltd. for Diamond Fields Namibia, January 2000. 62 pp.

HAMPTON, I. 1992. The role of acoustic surveys in the assessment of pelagic fish resources on the South

African continental shelf. South African Journal of Marine Science, 12: 1031-1050.

HAMPTON, I. 2001. Fishing Activities in Licence Area 2814A and Environs (28°-29° S; 14°-15° E).

HAMPTON, I. 2003. Harvesting the Sea. In: MOLLOY, F. & T. REINIKAINEN (Eds), 2003. Namibia`s

Marine Environment. Directorate of Environmental Affairs, Ministry of Environment & Tourism,

Namibia, 31-69.

HAMPTON, I., BOYER, D.C., PENNEY, A.J., PEREIRA, A.F. & SARDINHA, M.M. 1998. Integrated overview

of fisheries of the Benguela Current region. Thematic report for the Benguela Current Large Marine

Ecosystem Programme. Windhoek; United Nations Development Programme: 92 pp.

HANSEN. F.C., CLOETE. R.R. & VERHEYE, H.M. 2005. Seasonal and spatial variability of dominant

copepods along a transect off Walvis Bay (23ºS), Namibia. African Journal of Marine Science, 27:

55-63.

HOLTZHAUZEN, J.A., 2000. Population dynamics and life history of westcoast steenbras Lithognathus

aureti (Sparidae), and management options for the sustainable exploitation of the steenbras

resource in Namibian waters. PhD Thesis, University of Port Elizabeth: 233 pages.

HOLTZHAUSEN, J.A., KIRCHNER, C.H. & VOGES, S.F. 2001. Observations on the linefish resources of

Namibia, 1999-2000, with special reference to West Coast steenbras and silver kob. South African

Journal of Marine Science 23: 135-144.

HOWARD, J.A.E., JARRE, A., CLARK, A.E. & MOLONEY C.L., 2007. Application of the sequential t-test

algorithm or analyzing regime shifts to the southern Benguela ecosystem. African Journal of Marine

Science 29(3): 437-451.

HOVLAND, M., VASSHUS, S., INDREEIDE, A., AUSTDAL, L. & NILSEN, Ø. 2002. Mapping and imaging

deep-sea coral reefs off Norway, 1982-2000. Hydrobiol. 471: 13-17.

JACKSON, L.F. & McGIBBON, S. 1991. Human activities and factors affecting the distribution of macro-

benthic fauna in Saldanha Bay. S. Afr. J. Aquat. Sci., 17: 89-102.

KAMSTRA, F. 1985. Environmental features of the southern Benguela with special reference to the wind

stress. In: South African Ocean Colour and Upwelling Experiment. Shannon L.V. (ed.). Cape

Town. Sea Fisheries Research Institute: 13-27.

KEMPER, J., UNDERHILL, L.G., CRAWFORD, R.J.M. & S.P. KIRKMAN, 2007. Revision of the

conservation status of seabirds and seals breeding in the Benguela Ecosystem. In: KIRKMAN, S.P.

(ed). Final Report of the BCLME (Benguela Current Large Marine Ecosystem) Project on Top

Predators as Biological Indicators of Ecosystem Change in the BCLME: 325-342. Avian Demography

Unit, University of Cape Town, Cape Town, South Africa

KENDALL, M.A. & WIDDICOMBE, S. 1999. Small scale patterns in the structure of macrofaunal

assemblages of shallow soft sediments. Journal of Experimental Marine Biology & Ecology, 237:127-

140.

KENNY, A. J., REES, H. L., GREENING, J. & CAMPBELL, S. 1998. The effects of marine gravel extraction

on the macrobenthos at an experimental dredge site off north Norfolk, U.K. (Results 3 years post-

dredging). ICES CM 1998/V:14, pp. 1-8.

KENSLEY, B. 1980. Decapod and Isopod Crustaceans From the West Coast of Southern Africa, Including

Seamounts Vema and Tripp. Annals of the South African Museum, 83(2): 13-32.

KENSLEY, B. 1981. On the Zoogeography of Southern African Decapod Crustacea, With a Distributional

Checklist. Smithsonian Contributions to Zoology, 338: 1-64.

KIRCHNER, C.H. 2001. Fisheries regulations based on yield per recruit analysis for the linefish silver kob

Argyrosomus inodorus in Namibian waters. Fisheries Research, 52: 155–167.




EIA Report

October 2017

KIRCHNER, C.H., SAKKO, A. & BARNES, J.I. 2000. Estimation of the economic value of the Namibian

recreational rock-and-surf fishery. South African Journal of Marine Science 22: 17-25.

KOSLOW, J.A. 1996. Energetic and life history patterns of deep-sea benthic, benthopelagic and seamount

associated fish. Journal of Fish Biology, 49A: 54-74.

LAMBARDI, P., LUTJEHARMS, J.R.E., MENACCI, R., HAYS, G.C. and LUSCHI, P. 2008. Influence of

ocean currents on long-distance movement of leatherback sea turtles in the Southwest Indian

Ocean. Marine Ecology Progress Series, 353: 289–301.

LANE, S.B. & CARTER, R.A. 1999. Generic Environmental Management Programme for Marine Diamond

MIning off the West Coast of South Africa. Marine Diamond Mines Association, Cape Town, South

Africa. 6 Volumes.

LEHMENSIEK, A. 1995. Monitoring of the commercial tuna catches in Namibian waters. Annual Research

Meeting Report. Ministry of Fisheries and Marine Resources, Swakopmund.

LE ROUX, L. 1998. Research on Deepsea Red Crab after more than 20 years of Exploitation. Namibia Brief,

20: 126-128.

LEVIN, L.A. 2003. Oxygen minimum zone benthos: adaptation and community response to hypoxia.

Oceanography and Marine Biology: an Annual Review 41: 1-45.

LEVIN, L.A., WHITCRAFT, C.R., MENDOZA, G.F., GONZALEZ, J.P. and COWIE, G. 2009. Oxygen and

organic matter thresholds for benthic faunal activity on the Pakistan margin oxygen minimum zone

(700 - 1100 m). Deep-Sea Research II 56: 449-471.

LIPINSKI, M.R. 1992. Cephalopods and the Benguela ecosystem: trophic relationships and impact. In:

Benguela Trophic Functioning (eds A.I.L. Payne, K.H. Brink, K.H. Mann and R. Hilborn). South

African Journal of Marine Science 12: 791-802.

LOMBARD, A.T., STRAUSS, T., HARRIS, J., SINK, K., ATTWOOD, C. & HUTCHINGS, L. 2004. National

Spatial Biodiversity Assessment 2004: South African Technical Report Volume 4: Marine Component

LONGHURST, A. R. (2006) Ecological Geography of the Sea. 2nd

edition. Academic Press, San Diego. pp.

560.

LUDYNIA, K., 2007. Identification and characterisation of foraging areas of seabirds in upwelling systems:

biological and hydrographic implications for foraging at sea. PhD thesis, University of Kiel, Germany

LYNAM C.P., GIBBONS M.J., AXELSEN B.E., SPARKS C.A.J., COETZEE J., HAYWOOD B.G. &

BRIERLEY, A.S. 2006. Jellyfish overtake fish in a heavily fished ecosystem. Current Biology 16: 492-

493

MAARTENS, L. 2003. Biodiversity. In: MOLLOY, F. & REINIKAINEN, T. (Eds). Namibia’s Marine

Environment. Directorate of Environmental Affairs, Ministry of Environment and Tourism, Namibia:

103-135.

MacISSAC, K., BOURBONNAIS, C., KENCHINGTON, E.D., GORDON JR. & GASS, S. 2001. Observations

on the occurrence and habitat preference of corals in Atlantic Canada. In: (eds.) J.H.M. WILLISON,

J. HALL, S.E. GASS, E.L.R. KENCHINGTON, M. BUTLER, & DOHERTY, P. Proceedings of the

First International Symposium on Deep-Sea Corals. Ecology Action Centre and Nova Scotia

Museum, Halifax, Nova Scotia.

MacPHERSON, E. & GORDOA, A. 1992. Trends in the demersal fish community off Namibia from 1983 to

1990. South African Journal of Marine Science 12: 635-649.

MATE, B.R., BEST, P.B., LAGERQUIST, B.A. & WINSOR, M.H. 2011. Coastal, offshore and migratory

movements of South African right whales revealed by satellite telemetry. Marine Mammal Science,

27(3): 455-476.

MATE, B.R., LAGERQUIST, B.A., WINSOR, M., GERACI, J. & PRESCOTT, J.H. 2005. Movements and dive

habits of a satellite-monitored long-finned pilot whales (Globicephala melas) in the northwest

Atlantic. Marine Mammal Science 21 (1): 136-144.




EIA Report

October 2017

MATTHEWS, S.G. & PITCHER, G.C. 1996. Worst recorded marine mortality on the South African coast. In:

YASUMOTO, T, OSHIMA, Y. & Y. FUKUYO (Eds), Harmful and Toxic Algal Blooms.

Intergovernmental Oceanographic Commission of UNESCO, pp 89-92.

MATTHEWS, J.P. & SMIT, N.L. 1979. Trends in the size composition, availability, egg-bearing and sex ratio

of the rock lobster Jasus lalandii in its main fishing area off South West Africa, 1958-1969. Investl.

Rep. Div. Sea Fish. S. Afr., 103: 1-38

McCAULEY, R.D. 1994. Seismic surveys. In: Swan, J.M., Neff, J.M., Young, P.C. (Eds.). Environmental

implications of offshore oil and gas development in Australia - The findings of an Independent

Scientific Review. APEA, Sydney, Australia, 695 pp.

McLACHLAN, A. 1980. The definition of sandy beaches in relation to exposure: a simple rating system. S.

Afr. J. Sci., 76: 137-138.

McLACHLAN, A. 1986. Ecological surveys of sandy beaches on the Namib coast. Report No. 13, Institute

for Coastal Research, University of Port Elizabeth, Port Elizabeth

MECENERO, S., ROUX, J.-P., UNDERHILL, L.G. & M.N. BESTER, 2006. Diet of Cape fur seals

Arctocephalus pusillus pusillus at three mainland breeding colonies in Namibia. 1. Spatial variation.

African Journal of Marine Science, 28: 57-71.

MOLDAN, A.G.S. 1978. A study of the effects of dredging on the benthic macrofauna in Saldanha Bay.

South African Journal of Science, 74: 106-108.

MOLLOY, F. & REINIKAINEN, T. (Eds). 2003. Namibia`s Marine Environment. Directorate of Environmental

Affairs, Ministry of Environment & Tourism, Namibia, 160 pp.

MONTEIRO, P.M.S. & VAN DER PLAS, A.K. 2006. Low Oxygen Water (LOW) variability in the Benguela

System: Key processes and forcing scales relevant to forecasting. In: SHANNON, V., HEMPEL, G.,

MALANOTTE-RIZZOLI, P., MOLONEY, C. & J. WOODS (Eds). Large Marine Ecosystems, Vol. 15,

pp 91-109.

NELSON, G. 1989. Poleward motion in the Benguela area. In: Neshyba SJ, Mooers CNK, Smith RL,Barber

RT (Eds) Poleward Flows along Eastern Ocean Boundaries. Springer, New York, 110-130 (Coastal

and Estuarine Studies 34).

NELSON, G. & HUTCHINGS, L. 1983). The Benguela upwelling area. Progress in Oceanography, 12, 333–

356

NRC, 2003. Ocean noise and marine mammals. National Academy Press, Washington, DC.

NEWMAN, G.G. & POLLOCK, D.E. 1971. Biology and migration of rock lobster Jasus lalandii and their

effect on availability at Elands Bay, South Africa. Investl. Rep. Div. Sea Fish. S. Afr., 94: 1-24.

OLIVIER, J. 1992. Aspects of the climatology of fog in the Namib. SA geographer 19(2): 107-125.

OLIVIER, J. 1995. Spatial fog distribution pattern in the Namib using Meteosat images. J. Arid Environments

29: 129-138.

OOSTHUIZEN W.H. 1991. General movements of South African (Cape) fur seals Arctocephalus pusillus

pusillus from analysis of recoveries of tagged animals. S. Afr. J. Mar. Sci., 11: 21-30.

PARKINS, C.A. & FIELD J.G. 1997. A baseline study of the benthic communities of the unmined sediments

of the De Beers Marine SASA Grid. Unpublished Report to De Beers Marine, October 1997, pp 29.

PARKINS, C.A. & FIELD, J.G. 1998. The effects of deep sea diamond mining on the benthic community

structure of the Atlantic 1 Mining Licence Area. Annual Monitoring Report – 1997. Prepared for De

Beers Marine (Pty) Ltd by Marine Biology Research Institute, Zoology Department, University of

Cape Town. pp. 44.

PARRY, D.M., KENDALL, M.A., PILGRIM, D.A. & JONES, M.B. 2003. Identification of patch structure within

marine benthic landscapes using a remotely operated vehicle. J. Exp. Mar. Biol. Ecol., 285– 286:

497–511.

PAYNE, A.I.L. & CRAWFORD, R.J.M. 1989. Oceans of Life off Southern Africa. Vlaeberg, Cape Town, 380

pp.




EIA Report

October 2017

PEDDEMORS, V.M. 1999. Delphinids of southern Africa: a review of their distribution, status and life history.

J. Cet. Res. Manage. 1(2): 157-166.

PENNEY, A.J., KROHN, R.G. & WILKE. C.G. 1992. A description of the South African tuna fishery in the

southern Atlantic Ocean. ICCAT Col. Vol. Sci. Pap. XXIX(1) : 247-253.

PITCHER, G.C. 1998. Harmful algal blooms of the Benguela Current. IOC, World Bank and Sea Fisheries

Research Institute Publication. 20 pp.

PITCHER, G.C., BOYD, A.J. HORSTMAN, D.A. & MITCHELL-INNES, B.A. 1998. Subsurface dinoflagellate

populations, frontal blooms and the formation of red tide in the southern Benguela upwelling system.

Marine Ecology - Progress Series, VOL. 172, pp. 253-264.

PLÖN, S. 2004. The status and natural history of pygmy (Kogia breviceps) and dwarf (K. sima) sperm

whales off Southern Africa. PhD Thesis. Department of Zoology & Entomology (Rhodes University),

p. 551.

POLLOCK, D.E. & SHANNON, L.V. 1987. Response of rock-lobster populations in the Benguela ecosystem

to environmental change – a hypothesis. S. Afr. J. Mar. Sci., 5: 887-899.

POTTS, W.M., SAUER, W.H.H., HENRIQUES, R., SEQUESSEQUE, S., SANTOS, C.V. & SHAW. P.W.

2010. The biology, life history and management needs of a large sciaenid fish, Argyrosomus

coronus in Angola. African Journal of Marine Science 32 (2): 247 — 258.

PRDW, 2008. Nampower Walvis Bay ESEIA Specialist Study: Hydrodynamic modelling of heated effluent in

marine environment, PRDW Report No. 1024/001, Prestedge Retief Dresner Wijnberg (Pty) Ltd

Consulting Port and Coastal Engineers, 23 pp + 63 pp Figs.

PULFRICH A. & PENNEY, A.J. 1999a. Assessment of the impact of diver-operated nearshore diamond

mining on marine benthic communities near Lüderitz, Namibia. Final Report to NAMDEB Diamond

Corporation (Pty) Ltd., Oranjemund, Namibia, 40 pp.

PULFRICH, A. & PENNEY, A.J. 1999b. The effects of deep-sea diamond mining on the benthic community

structure of the Atlantic 1 Mining Licence Area. Annual Monitoring Report – 1998. Prepared for De

Beers Marine (Pty) Ltd by Marine Biology Research Institute, Zoology Department, University of

Cape Town and Pisces Research and Management Consultants CC. pp 49.

ROEL, B.A., 1987. Demersal communities off the west coast of South Africa. South African Journal of Marine

Science 5: 575-584.

ROGERS, A.D. 2004. The biology, ecology and vulnerability of seamount communities. IUCN, Gland,

Switzerland. Available at: www.iucn.org/themes/ marine/pubs/pubs.htm 12 pp.

ROGERS, J. 1987. Seismic, bathymetric and photographic evidence of widespread erosion and a

manganese-nodule pavement along the continental rise of the Southeast Cape basin. Marine

Geology, 78: 57-76.

ROGERS, J. 1995. A comparative study of manganese nodules off southern Africa. South African Journal of

Geology, 98: 208-216.

ROGERS, J. and BREMNER, J.M. 1991. The Benguela ecosystem. Part 7. Marine-geological aspects.

Oceanography and Marine Biology: an Annual Review, vol. 29, pp. 1-85.

ROSE, B. & PAYNE, A.I.L. 1991. Occurrence and behaviour of Southern right-whale dolphin Lissodelphis

peronii off Namibia. Mar. Mamm. Sci., 7 (1): 25-34.

ROSENBAUM, H.C., POMILLA, C., MENDEZ, M., LESLIE, M.S., BEST, P.B., FINDLAY, K.P., MINTON, G.,

ERSTS, P.J., COLLINS, T., ENGEL, M.H., BONATTO, S., KOTZE, P.G.H., MEŸER, M.,

BARENDSE, J., THORNTON, M., RAZAFINDRAKOTO, Y., NGOUESSONO, S., VELY, M. &

KISZKA, J. 2009. Population structure of humpback whales from their breeding grounds in the South

Atlantic and Indian Oceans. PLoS One, 4 (10): 1-11.

ROSS, G.J.B. 1984. The smaller cetaceans of the south East Coast of southern Africa. Ann. Cape. Prov.

Mus (nat. Hist) 15(2).




EIA Report

October 2017

ROUX, J-P., BEST, P.B. & STANDER, P.E. 2001. Sightings of southern right whales (Eubalaena australis) in

Namibian waters, 1971-1999. J. Cetacean Res. Manage. (special issue 2):181-185.

ROUX, J-P., BRADY, R. & BEST, P.B. 2011. Southern right whales off Namibian and their relationship with

those off South Africa. Paper SC/S11/RW16 submitted to IWC Southern Right Whale Assessment

Workshop, Buenos Aires 13-16 Sept. 2011.

ROUX, J-P., BRADY, R. & BEST, P.B. 2015. Does disappearance mean extirpation? The case of right

whales off Namibia. Marine Mammal Science 31(3): 1132-1152.

SCHNEIDER, G. and MUYONGO, A. 2013. Hydrocarbon exploration and Albacore Tuna fisheries – A

classical example for the role of BCC in joint and transboundary management of the BCLME.

Presented at the Benguela Current Commission Science Forum, 24 September 2013.

SEIDERER, L.J. & NEWELL, R.C. 1999. Analysis of the relationship between sediment composition and

benthic community structure in coastal deposits: Implications for marine aggregate dredging. ICES

Journal of Marine Science, 56: 757–765.

SHANNON, L.V. & M.J. O’TOOLE, 1998. BCLME Thematic Report 2: Integrated overview of the

oceanography and environmental variability of the Benguela Current region. Unpublished BCLME

Report, 58ppSIMMONDS, M.P., and LOPEZ – JURADO, L.F. 1991. Nature. 337: 448.

SHANNON, L. V. 1985. The Benguela Ecosystem, Part I. Evolution of the Benguela, physical features and

processes. Oceanography and Marine Biology: An Annual Review, 23, 105–182.

SHANNON, L.V. & NELSON, G. 1996. The Benguela: large scale features and processes and system

variability. In G. Wefer, W. H. Berger, G. Siedler, & D. J. Web (Eds.), The South Atlantic: present and

past circulation (pp. 163–210). Berlin, Heidelberg: Springer-Verlag.

SHANNON, L.V. & F.P. ANDERSON, 1982. Application of satellite ocean colour imagery in the study of the

Benguela Current system. S. Afr. J. Photogrammetry, Remote Sensing and Cartography, 13(3):

153-169.

SHANNON, L.J., C.L. MOLONEY, A. JARRE & J.G. FIELD, 2003. Trophic flows in the southern Benguela

during the 1980s and 1990s. Journal of Marine Systems, 39: 83 - 116.

SHILLINGTON, F.A., HUTCHINGS, L., PETERSON, W.T., PROBYN, T. A., WALDRON, H.N. & AGENBAG,

J.J. 1990. A cool upwelling filament off Namibia, southwest Africa: preliminary measurements of

physical and biological features. Deep-Sea Research A, 37, 1753–1772.

SIMMONS, R.E., BARNES, K.N. JARVIS, A.M. & ROBERTSON, A. 1999. Important Bird Areas in Namibia.

Research Discussion Paper No. 31. DEA of MET, 68pp.

SIMMONS, R.E. and BROWN, C.J. (in press). Birds to watch in Namibia: red, rare and endemic species.

National Biodiversity Programme, Windhoek, Namibia

SMALE, M.J., ROEL, B.A., BADENHORST, A. & FIELD, J.G. 1993. Analysis of demersal community of fish

and cephalopods on the Agulhas Bank, South Africa. Journal of Fisheries Biology 43:169-191.

SMITH, G.G & G.P. MOCKE, 2002. Interaction between breaking/broken waves and infragravity-scale

phenomena to control sediment sediment suspension and transport in the surf zone. Marine

Geology, 187: 320-345.

SNELGROVE, P.V.R. & BUTMAN, C.A. 1994. Animal-sediment relationships revisited: cause versus effect.

Oceanography & Marine Biology: An Annual Review, 32: 111-177.

SPRFMA. 2007: Information describing seamount habitat relevant to the South Pacific Regional Fisheries

Management Organisation.

STEFFANI, N. 2007a. Biological Baseline Survey of the Benthic Macrofaunal Communities in the Atlantic 1

Mining Licence Area and the Inshore Area off Pomona for the Marine Dredging Project. Prepared for

De Beers Marine Namibia (Pty) Ltd. pp. 42 + Appendices.

STEFFANI, C.N. 2007b. Biological Monitoring Survey of the Macrofaunal Communities in the Atlantic 1

Mining Licence Area and the Inshore Area between Kerbehuk and Bogenfels. 2005 Survey.

Prepared for De Beers Marine Namibia (Pty) Ltd. pp. 51 + Appendices.




EIA Report

October 2017

STEFFANI, N. 2009a. Biological Monitoring Surveys of the Benthic Macrofaunal Communities in the Atlantic

1 Mining Licence Area and the Inshore Area – 2006/2007. Prepared for De Beers Marine Namibia

(Pty) Ltd. (Confidential Report) pp. 81 + Appendices.

STEFFANI, N. 2009b. Assessment of Mining Impacts on Macrofaunal Benthic Communities in the Northern

Inshore Area of the De Beers ML3 Mining Licence Area - 18 Months Post-mining. Prepared for De

Beers Marine. pp. 47 + Appendices.

STEFFANI, N. 2009c. Baseline Study on Benthic Macrofaunal Communities in the Inner Shelf Region and

Assessment of Mining Impacts off Chameis. November 2009. Prepared for Namdeb. pp. 45 +

Appendices.

STEFFANI, C.N. & PULFRICH, A. 2004a. Environmental Baseline Survey of the Macrofaunal Benthic

Communities in the De Beers ML3/2003 Mining Licence Area. Prepared for De Beers Marine South

Africa, April 2004., 34pp.

STEFFANI, N. & PULFRICH A. 2004b. The potential impacts of marine dredging operations on benthic

communities in unconsolidated sediments. Specialist Study 2. Specialist Study for the Environmental

Impact Report for the Pre-feasibility Phase of the Marine Dredging Project in Namdeb’s Atlantic 1

Mining Licence Area and in the nearshore areas off Chameis. Prepared for PISCES Environmental

Services (Pty) Ltd, September 2004.

STEFFANI, C.N. & PULFRICH, A. 2007. Biological Survey of the Macrofaunal Communities in the Atlantic 1

Mining Licence Area and the Inshore Area between Kerbehuk and Lüderitz 2001 – 2004 Surveys.

Prepared for De Beers Marine Namibia, March 2007, 288pp.

STEFFANI, C.N. 2009. Assessment of Mining Impacts on Macrofaunal Benthic Communities in the Northern

Inshore Area of the De Beers ML3 Mining Licence Area - 18 Months Post-mining. Prepared for De

Beers Marine (South Africa), 47pp.

STEFFANI, C.N. 2010. Assessment of mining impacts on macrofaunal benthic communities in the northern

inshore area of the De Beers Mining Licence Area 3 – 2010 . Prepared for De Beers Marine (South

Africa). pp 30 + Appendices.

STEFFANI, N. 2011. Environmental Impact Assessment for the dredging of Marine Phosphate Enriched

Sediments from Mining Licence Area No. 170. Specialist Study No. 1c: Marine Benthic Specialist

Study for a Proposed Development of Phosphate Deposits in the Sandpiper Phosphate Licence Area

off the Coast of Central Namibia. Prepared for Namibian Marine Phosphate (Pty) Ltd. November

2011. 72 pp.

STEFFANI, C.N. 2012. Assessment of Mining Impacts on Macrofaunal Benthic Communities in the Northern

Inshore Area of the ML3 Mining Licence Area - 2011. Prepared for De Beers Marine (South Africa),

July 2012, 54pp.

THOMISCH, K., BOEBEL, O., CLARK, C.W., HAGEN, W., SPIESECKE, S., ZITTERBART, D.P. & VAN

OPZEELAND, I. 2016. Spatio-temporal patterns in acoustic presence and distribution of Antarctic

blue whales Balaenoptera musculus intermedia in the Weddell Sea. Endangered Species Research,

30: 239-253.

TIMONIN, A.G., ARASHKEVICH, E.G., DRITS, A.V. & SEMENOVA, T.N. 1992. Zooplankton dynamics in

the northern Benguela ecosystem, with special reference to the copepod Calanoides carinatus. In:

PAYNE, A.I.L., BRINK, K.H., MANN, K.H. & R. HILBORN (Eds). Benguela Trophic Functioning. S.

Afr. J. mar. Sci. 12: 545–560.

VAN DALFSEN, J.A., ESSINK, K., TOXVIG MADSEN, H., BIRKLUND, J., ROMERO, J. & MANZANERA, M.

2000. Differential response of macrozoobenthos to marine sand extraction in the North Sea and the

Western Mediterranean. ICES J. Mar. Sci., 57: 1439–1445.

VAN DER LINGEN, C.D., SHANNON, L.J., CURY, P., KREINER, A., MOLONEY. C.L., ROUX, J-P. & VAZ-

VELHO, F. 2006. Resource and ecosystem variability, including regime shifts, in the Benguela

Current System. Pages 147–185. In Benguela: Predicting a Large Marine Ecosystem (V. Shannon,

G. Hempel, P. Malanotte-Rizzoli, C.L. Moloney, J. Woods, Eds.). Elsevier, Amsterdam.




EIA Report

October 2017

WARD, L.G., 1985. The influence of wind waves and tidal currents on sediment resuspension in Middle

Chesapeake Bay. Geo-Mar. Letters, 5: 1-75.

WARWICK, R.M., GOSS-CUSTARD, J.D., KIRBY, R., GEORGE, C.L., POPE, N.D. & ROWDEN, A.A. 1991.

Static and dynamic environmental factors determining the community structure of estuarine

macrobenthos in SW Britain: why is the Severn estuary different? J. Appl. Ecol., 28: 329–345.

WEEKS, S., CURRIE, B. & A. BAKUN, A. 2002. Massive emissions of toxic gas in the Atlantic. Nature, 415:

493-494.

WEEKS, S.J., CURRIE, B., BAKUN, A. & PEARD, K.R. 2004. Hydrogen sulphide eruptions in the Atlantic

Ocean off southern Africa: implications of a new view based on SeaWiFS satellite imagery. Deep-

Sea Res. I, 51:153-172.

WEIR, C.R., COLLINS, T., CARVALHO, I. & H.C. ROSENBAUM, 2010. Killer whales (Orcinus orca) in

Angolan and Gulf of Guinea waters, tropical West Africa. Journal of the Marine Biological Association

of the U.K. 90: 1601– 1611.

WEIR, C.R. 2011 Distribution and seasonality of cetaceans in tropical waters between Angola and the Gulf of

Guinea. African Journal of Marine Science 33(1): 1-15.

WEIR C.R., 2008. Bottlenose dolphins (Tursiops truncatus) off flamingos, Angola. Photo-identification

catalogue. Ketos Ecology Version 1, August 2008. www.ketosecology.co.uk.

WHITEHEAD, H. 2002. Estimates of the current global population size and historical trajectory for sperm

whales. Marine Ecology Progress Series, 242: 295-304.

YANG, R. & SUN, C. 1983. Distribution, yield and overall fishing intensity of Atlantic albacore caught by the

longline fishery, 1967-1991. Acta Ocean. Taiwan. 14: 100-118.

YATES, M.G., GOSS-CUSTARD, J.D., MCGRORTY, S.M., LAKHANI, DIT DURRELL, S.E.A., LEVIT,

CLARKE, R.T., RISPIN, W.E., MOY, I., YATES, T., PLANT, R.A. & FROST, A.J. 1993. Sediment

characteristics, invertebrate densities and shorebird densities on the inner banks of the Wash. J.

Appl. Ecol., 30: 599– 614.

ZAJAC, R.N., LEWIS, R.S., POPPE, L.J., TWICHELL, D.C., VOZARIK, J. and DIGIACOMO-COHEN, M.L.

2000. Relationships among sea-floor structure and benthic communities in Long Island Sound at

regional and benthoscape scales. J. Coast. Res., 16: 627– 640.

ZEYBRANDT, F. & BARNES, J.I. 2001. Economic characteristics of demand in Namibia's marine

recreational shore fishery. South African Journal of Marine Science, 23: 145-156.

ZOUTENDYK, P., 1992. Turbid water in the Elizabeth Bay region: A review of the relevant literature. CSIR

Report EMAS-I 92004.

ZOUTENDYK, P., 1995. Turbid water literature review: a supplement to the 1992 Elizabeth Bay Study.

CSIR Report EMAS-I 95008.




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October 2017

APPENDIX 1

CONVENTION FOR ASSIGNING

SIGNIFICANCE RATINGS TO IMPACTS

Spectrum: 3D seismic survey off the coast of northern Namibia

SLR Environmental Consulting (Namibia) (Pty) Ltd Significance ratings 1

CONVENTION FOR ASSIGNING SIGNIFICANCE RATINGS TO IMPACTS

1. EXTENT

“Extent” defines the physical extent or spatial scale of the impact.

Rating Description

LOCAL Extending only as far as the activity, limited to the site and its immediate surroundings.

Specialist studies to specify extent.

REGIONAL Limited to the Northern Namibian Coast.

NATIONAL Limited to the coastline of Namibia.

2. DURATION

“Duration” gives an indication of how long the impact would occur.

Rating Description

SHORT TERM 0 - 5 years

MEDIUM TERM 6 - 15 years

LONG TERM Where the impact would cease after the operational life of the activity, either because of natural

process or human intervention.

PERMANENT Where mitigation either by natural processes or by human intervention would not occur in such

a way or in such time span that the impact can be considered transient.

3. INTENSITY

“Intensity” establishes whether the impact would be destructive or benign.

Rating Description

ZERO TO VERY

LOW

Where the impact affects the environment in such a way that natural, cultural and social

functions and processes are not affected.

LOW Where the impact affects the environment in such a way that natural, cultural and social

functions and processes continue, albeit in a slightly modified way.

MEDIUM Where the affected environment is altered, but natural, cultural and social functions and

processes continue, albeit in a modified way.

HIGH Where natural, cultural and social functions or processes are altered to the extent that it will

temporarily or permanently cease.



4. SIGNIFICANCE

“Significance” attempts to evaluate the importance of a particular impact, and in doing so incorporates the

above three scales (i.e. extent, duration and intensity).

Rating Description

VERY HIGH Impacts could be EITHER:

of high intensity at a regional level and endure in the long term1;

OR of high intensity at a national level in the medium term;

OR of medium intensity at a national level in the long term.

HIGH Impacts could be EITHER:

of high intensity at a regional level and endure in the medium term;

OR of high intensity at a national level in the short term;

OR of medium intensity at a national level in the medium term;

OR of low intensity at a national level in the long term;

OR of high intensity at a local level in the long term;

OR of medium intensity at a regional level in the long term.

MEDIUM Impacts could be EITHER:

of high intensity at a local level and endure in the medium term;

OR of medium intensity at a regional level in the medium term;

OR of high intensity at a regional level in the short term;

OR of medium intensity at a national level in the short term;

OR of medium intensity at a local level in the long term;

OR of low intensity at a national level in the medium term;

OR of low intensity at a regional level in the long term.

LOW Impacts could be EITHER

of low intensity at a regional level and endure in the medium term;

OR of low intensity at a national level in the short term;

OR of high intensity at a local level and endure in the short term;

OR of medium intensity at a regional level in the short term;

OR of low intensity at a local level in the long term;

OR of medium intensity at a local level and endure in the medium term.

VERY LOW Impacts could be EITHER

of low intensity at a local level and endure in the medium term;

OR of low intensity at a regional level and endure in the short term;

OR of low to medium intensity at a local level and endure in the short term.

INSIGNIFICANT Impacts with:

Zero to very low intensity with any combination of extent and duration.

UNKNOWN In certain cases it may not be possible to determine the significance of an impact.

5. STATUS OF IMPACT

The status of an impact is used to describe whether the impact would have a negative, positive or zero

effect on the affected environment. An impact may therefore be negative, positive (or referred to as a

benefit) or neutral.

1 For any impact that is considered to be “Permanent” apply the “Long-Term” rating.



6. PROBABILITY

“Probability” describes the likelihood of the impact occurring.

Rating Description

IMPROBABLE Where the possibility of the impact to materialise is very low either because of design or

historic experience.

PROBABLE Where there is a distinct possibility that the impact would occur.

HIGHLY PROBABLE Where it is most likely that the impact would occur.

DEFINITE Where the impact would occur regardless of any prevention measures.

7. DEGREE OF CONFIDENCE

This indicates the degree of confidence in the impact predictions, based on the availability of information

and specialist knowledge.

Rating Description

HIGH Greater than 70% sure of impact prediction.

MEDIUM Between 35% and 70% sure of impact prediction.

LOW Less than 35% sure of impact prediction.

APPENDIX 2

FISHERIES ASSESSMENT

PROPOSED 3D SEISMIC SURVEY OFFSHORE NORTHERN NAMIBIA

Baseline Study and Environmental Impact Assessment on Fisheries

Compiled for:

On behalf of:

Prepared by:

D.W. Japp and S. Wilkinson

Cape Town

June 2017

SPECTRUM GEO CAPRICORN MARINE ENVIRONMENTAL PTY LTD Page i

PROPOSED 3D SEISMIC SURVEY, NORTHERN NAMIBIA Fisheries Assessment

INDEX

Expertise and Declaration of Independence ...................................................................................................................................... iii

Executive Summary ........................................................................................................................................................................... iii

1. INTRODUCTION ..................................................................................................................................................................... 1

1.1 Typical Seismic Surveys ............................................................................................................................................ 2

1.1.1 Survey Methodology and Airgun Array ................................................................................................................. 2

1.1.2 Sound Pressure Emission Levels ......................................................................................................................... 3

1.1.3 Recording Equipment ............................................................................................................................................ 4

1.2 Description of Seismic Survey Impacts on Fisheries ................................................................................................. 4

1.2.1 Exclusion Zone ...................................................................................................................................................... 4

1.2.2 Acoustic Impacts ................................................................................................................................................... 4

2. METHODS ............................................................................................................................................................................... 5

3. DATA SOURCES .................................................................................................................................................................... 6

4. DESCRIPTION OF AFFECTED ENVIRONMENT .................................................................................................................. 7

4.1 Overview of Namibian Fisheries ................................................................................................................................ 7

4.1 Overview of Angolan Fisheries .................................................................................................................................. 8

4.2 Stock Distribution, Spawning and Recruitment ........................................................................................................ 10

4.3 Small Pelagic Purse-Seine ...................................................................................................................................... 12

4.4 Mid-Water Trawl ....................................................................................................................................................... 15

4.5 Demersal Trawl ........................................................................................................................................................ 18

4.6 Deep-Water Trawl .................................................................................................................................................... 21

4.7 Deep-Sea Crab ........................................................................................................................................................ 22

4.8 Rock Lobster ............................................................................................................................................................ 24

4.9 Demersal Long-Line ................................................................................................................................................. 25

4.10 Large Pelagic Long-Line ..................................................................................................................................... 27

4.11 Tuna Pole ............................................................................................................................................................ 30

4.12 Line-Fish ............................................................................................................................................................. 32

4.14 Fisheries Research ............................................................................................................................................. 33

5. SUMMARY AND RECOMMENDATIONS ............................................................................................................................. 35

6. REFERENCES ...................................................................................................................................................................... 37

APPENDIX 1: CONVENTION FOR ASSIGNING SIGNIFICANCE RATINGS TO IMPACTS .......................................................... 39

SPECTRUM GEO CAPRICORN MARINE ENVIRONMENTAL PTY LTD Page ii


LIST OF ACRONYMS AND ABBREVIATIONS

BCC Benguela Current Commission

dB Decibels

DNPPRP Direcção Nacional de Pesca e Protecção do Recursos

FAO Food and Agricultural Organization

GDP Gross Domestic Product

ha Hectare

INIP Instituto Nacional de Investigacao Pesqueiro

IPA Institute for the Development of Artisanal Fisheries and Aquaculture

kg Kilogram

kHz Kilohertz

MCS Monitoring, Control and Surveillance


MME Ministry of Mines and Energy

m Metre

ML Mining Licence

SANHO South African Navy Hydrographic Office

SLR SLR Environmental Consulting (Namibia) (Pty) Limited

t Metric tonne


µPa Micropascal

VMS Vessel Monitoring System

SPECTRUM GEO CAPRICORN MARINE ENVIRONMENTAL PTY LTD Page iii


06 May 2016

EXPERTISE AND DECLARATION OF INDEPENDENCE

26 January 2017

This report was prepared by David Japp and Sarah Wilkinson of CapMarine (Pty) Ltd. David Japp has a BSC in Zoology,

University of Cape Town (UCT) and an MSc degree in Fisheries Science from Rhodes University. Sarah Wilkinson has a

BSc (Hons) degree in Botany from UCT. Both are professional natural scientists registered with the SA Council for Natural

Scientific Professions (SACNASP).

Mr Japp has worked in the field of Fisheries Science and resource assessment since 1987 and has considerable experience

in undertaking specialist environmental impact assessments relating to fishing and fish stocks. His work has included

environmental economic assessments and the evaluation of the environmental impacts on fishing. Sarah Wilkinson has

worked on marine resource assessments, specializing in spatial and temporal analysis (GIS) as well as the economic

impacts of fisheries exploitation in the southern African region.

This specialist report was compiled for SLR Environmental Consulting (Namibia) (Pty) Ltd for their use in compiling an EIA

for the proposed 3D seismic survey offshore northern Namibia. We do hereby declare that we are financially and otherwise

independent of the Applicant and of SLR Environmental Consulting (Namibia) (Pty) Ltd.

Dave Japp

Sarah Wilkinson

SPECTRUM GEO CAPRICORN MARINE ENVIRONMENTAL PTY LTD Page iv


EXECUTIVE SUMMARY

Spectrum Geo Limited is proposing to undertake a speculative three-dimensional (3D) seismic survey to investigate for oil and

gas reserves within the Namibe Basin, off the coast of northern Namibia. The proposed 3D seismic survey would cover an area

of approximately 12 940 km2 in water depths ranging from 150 m to over 4000 m. It is anticipated that the survey would take in

the order of nine to ten months to complete and would commence in the fourth quarter of 2017.

The proposed survey could potentially affect fisheries that operate within the area through the temporary exclusion from fishing

grounds. It is likely that several Namibian fishing sectors would be affected by the proposed survey namely (1) the small pelagic

purse-seine, (2) mid-water trawl, (3) demersal trawl, (4) deep-sea crab, (5) demersal long-line and (6) large pelagic long-line

sectors. The significance of the impact of the proposed survey on each of the sectors ranges from very low (small pelagic purse-

seine and demersal long-line), low (demersal trawl) to medium (mid-water trawl, large pelagic long-line and deep-sea crab). There

is no impact expected on the deep-water trawl, rock lobster, tuna pole and linefish sectors. Biomass estimation of demersal

species (trawl surveys) and small pelagic species (acoustic surveys) are undertaken within the proposed seismic survey area

each year. These surveys are carried out during fixed periods (January and February for demersal trawls and late February to

March for acoustic surveys of small pelagic species). The impact of the proposed seismic survey on fisheries research surveys is

assessed to be of overall medium (acoustic) to very low (demersal) significance without mitigation, and of low (acoustic) to very

low (demersal) significance with mitigation. The significance of the impact could be minimised by allowing research survey

activities to be undertaken as necessary and this could be achieved through at-sea communications between the seismic and

research survey vessels.

The following general mitigation measures are proposed in order to minimise disruptions to both the survey and fishing

operations:

1. Prior to the commencement of the survey, the fishing industry, the Ministry of Fisheries and Marine Resources (MFMR)

and other interested and affected parties should be informed of the pending activity and the likely implications for the

various fishing sectors in the area;

2. Radio Navigational Warnings should be issued for the duration of the surveying operations through the South African

Naval Hydrographic Office (SANHO) and daily notifications should be issued by Walvis Bay Radio;

3. An experienced Fisheries Liaison Officer (FLO) should be deployed on board the survey or support vessel to facilitate

communication with maritime vessels. The FLO should report daily on vessel activity and respond and advise on action

to be taken in the event of encountering fishing gear;

4. A daily electronic reporting routine should be set up to keep interested and affected parties informed of survey activity,

fisheries interactions and environmental issues;

5. Due the likely interaction with fishers and fishing gear it is strongly recommended that the survey vessel be

accompanied by a chase vessel with staff familiar with the fishers expected in the area.

6. The impact on each fishery has been assessed based on the spatial overlap of fishing grounds by the cumulative

survey area and therefore assumes the scenario that fishing activity would be excluded from the entire area. In reality,

the exclusion zone covers only a portion of the cumulative survey area as the vessel progresses systematically from

one part of the project area to another over the course of 10 months. It is therefore unlikely that fishing vessels would

be excluded from operating within the entire survey area for the full duration of the project. It is possible that time-

sharing of the project area could be achieved with pro-active and on-going communications between the survey and

fishing vessels. This time-sharing would be strongly encouraged as a means of reducing the impact on fisheries that

operate within the survey area, in particular the midwater trawl fishery.

Communications with the fishing industry should be established through the Association of Namibian Fishing Industries (covers

most sectors as a collective secretariat). In addition, the Namibian Hake Association, Namibian Monk and Sole Association,

Midwater Trawling Association of Namibia, Namibian Tuna and Hake Longlining Association and Pelagic Fishing Association

should be notified. The operator of crab trap vessels should be contacted directly and informed of the intended survey period.

With respect to research cruises undertaken by MFMR and the Benguela Current Commission (BCC), it is advised that there be

consultation with these organisations prior to the commencement of the project to coordinate and minimise possible disruption of

any research surveys that might coincide with the proposed seismic survey.

SPECTRUM GEO CAPRICORN MARINE ENVIRONMENTAL PTY LTD Page 1


1. INTRODUCTION

Spectrum Geo Limited (hereafter referred to as “Spectrum”) is proposing to undertake a speculative three-dimensional (3D)

seismic survey to investigate for oil and gas reserves in the Namibe Basin off the coast of northern Namibia. The proposed 3D

seismic survey would be 12 940 km2 in extent in water depths between 150 m and over 4000 m (see Figure 1). Although survey

commencement would ultimately depend on when survey clearance is obtained, Spectrum proposes to commence with the 3D

seismic survey in the fourth quarter of 2017. It is anticipated that the survey would take in the order of nine to ten months to

complete.

Figure 1: Location of the proposed 3D survey area in the Namibe Basin off the coast of northern Namibia (after Spectrum,

January 2017).

Spectrum has applied to undertake the seismic survey under a Multi-Client Agreement with the National Petroleum Corporation of

Namibia (NAMCOR). SLR Environmental Consulting (Namibia) (Pty) Ltd (SLR) has been appointed to investigate the baseline

environmental conditions in the proposed survey area and to assess the potential impacts of the proposed seismic survey and

present the findings in an Environmental Impact Assessment (EIA) report. The EIA report presents the findings and

recommendations of the EIA process and is submitted to the Ministry of Mines and Energy (MME) for approval in consultation

with other relevant Ministries, e.g. the Ministry of Fisheries and Marine Resources (MFMR) and the Ministry of Environment and

Tourism (MET). Capricorn Marine Environmental (Pty Ltd (hereafter referred to as “CapMarine”) has been appointed by SLR to

undertake the Fisheries Assessment component of the EIA.



1.1 TYPICAL SEISMIC SURVEYS

Seismic surveys are carried out during oil and gas exploration activities in order to investigate subsea geological formations.

During seismic surveys, high-level, low frequency sounds are directed towards the seabed from near-surface sound sources

(source arrays) towed by a seismic vessel. Signals reflected from geological interfaces below the seafloor are recorded by

multiple receivers (or hydrophones) towed in a single or multiple streamer configuration (see Figure 2). Analyses of the returned

signals allow for interpretation of subsea geological formations.

Seismic surveys are undertaken to collect geophysical data in either 2D or 3D mode. 2D seismic surveys are typically acquired to

obtain regional data from widely spaced survey grids (tens of kilometres). 3D seismic surveys are typically acquired over

promising petroleum prospects to assist in fault interpretation, distribution of sand bodies, estimates of oil and gas in place and

the location of boreholes. For this investigation Spectrum is proposing to undertake a 3D seismic survey.

Figure 2: Principles of offshore seismic acquisition surveys (from fishsafe.eu).

1.1.1 SURVEY METHODOLOGY AND AIRGUN ARRAY

Seismic surveys are usually conducted using a purpose-built seismic vessel. Such vessels are approximately 50 to 65 m in

length with a Gross Registered Tonnage (GRT) between 1 000 and 6 500 t. The seismic vessel would travel along specific pre-

plotted survey lines covering a prescribed grid within the survey area that have been carefully chosen to cross any known or

suspected geological structure. During surveying, the seismic vessel would travel on specific line headings at a speed of

between four and five knots (i.e. 2 to 3 metres per second). With equipment deployed the vessel would have limited

manoeuvrability.

The seismic survey would typically involve a towed airgun array, which provides the seismic source energy for the profiling

process, and a seismic wave detector system, usually known as a hydrophone streamer. The anticipated airgun and hydrophone

array would be dependent on whether a 2D or 3D seismic survey is undertaken. The sound source or airgun array (one for 2D

and two for 3D) would be situated some 80 m to 150 m behind the vessel at a depth of 5 m to 25 m below the surface. A 2D

survey typically involves a single streamer, whereas 3D surveys use multiple streamers (up to 12 streamers spaced 100 m apart).

The array can be up to 12 000 m long. The streamer/s would be towed at a depth of between 6 m and 30 m and would not be

visible, except for the tail-buoy at the far end of the cable. A typical 3D seismic survey configuration and safe operational limits

are illustrated in Figure 3.



At all times, the survey vessel would be accompanied by at least one support vessel. Support vessels would act as guard

vessels for the towed equipment, would clear surface debris/obstructions in the path of the main acquisition vessel and inform

local shipping and fishing traffic of the nature of the operation in the area.

Figure 3: Typical configuration and safe operational limits for 3D seismic survey operations.

1.1.2 SOUND PRESSURE EMISSION LEVELS

Airguns, which are the most common sound source used in modern seismic surveys, would be used for the proposed survey.

The airgun is an underwater pneumatic device from which high-pressure air is released suddenly into the surrounding water. On

release of pressure the resulting bubble pulsates rapidly producing an acoustic signal that is proportional to the rate of change of

the volume of the bubble. The frequency of the signal depends on the energy of the compressed air prior to discharge. Airguns

are used on an individual basis (usually for shallow water surveys) or in arrays. Arrays of airguns are made up of towed parallel

strings, usually comprised of a total of 20 to 40 airguns.

Airguns have most of their energy in the 0-120 Hz frequency range,

with the optimal frequency required for deep penetration seismic

work being 50-80 Hz. The maximum sound pressure levels at the

source of airgun array would be in the range 220-230 dB re 1µ Pa

at 1 m (McCauley 1994; NRC 2003).

One of the required characteristics of a seismic shot is that it is of

short duration (the main pulse is usually between 5 and 30

milliseconds in duration). The main pulse is followed by a negative

pressure reflection from the sea surface of several lower magnitude

bubble pulses (see Figure 4). Despite peak levels within each shot

being high, the total energy delivered into the water is low.

Paravane

3 km

4 km

4 km

3 km

8 km

12 km

6 km 6 km

Airgun array


Tail-buoys



Not to scale

Figure 4: A typical pressure signature produced on firing of an airgun.



1.1.3 RECORDING EQUIPMENT

Signals reflected from geological discontinuities below the seafloor are recorded by hydrophones mounted inside streamer

cables. Hydrophones are typically made from piezoelectric material encased in a rubber plastic hose. This hose containing the

hydrophones is called a streamer. The reflected acoustic signals are recorded and transmitted to the seismic vessel for electronic

processing. Analyses of the returned signals allow for interpretation of subsea geological formations.

1.2 DESCRIPTION OF SEISMIC SURVEY IMPACTS ON FISHERIES

1.2.1 EXCLUSION ZONE

The acquisition of high quality seismic data requires that the position of the survey vessel and the array be accurately known.

Seismic surveys consequently require accurate navigation of the sound source over pre-determined survey transects. This, and

the fact that the array and the hydrophone streamer need to be towed in a set configuration behind the tow-ship, means that the

survey operation has little manoeuvrability while operating. For this reason the vessel is considered to be a fixed marine feature

that is to be avoided by other vessels.

Under the Convention on the International Regulations for Preventing Collisions at Sea (COLREGS, 1972, Part A, Rule 10), a

seismic survey vessel that is engaged in surveying is defined as a “vessel restricted in its ability to manoeuvre” which requires

that power-driven and sailing vessels give way to a vessel restricted in her ability to manoeuvre. Vessels engaged in fishing shall,

so far as possible, keep out of the way of the seismic survey operation. Furthermore, in terms of the Petroleum (Exploration and

Production) Act, 1991 (No. 2 of 1991) a seismic vessel is considered to be an “offshore installation” and as such it is protected by

a 500 m safety zone. It is an offence for an unauthorised vessel to enter the safety zone. In addition to a statutory 500 m safety

zone, a seismic contractor would request a safe operational limit (that is greater than the 500 m safety zone) that it would like

other vessels to stay beyond. Typical safe operational limits for 3D surveys are illustrated in Figure 3.

At least a 500 m safety zone would need to be enforced around the survey vessel (including its array of airguns and streamer) at

all times. A support vessel with appropriate radar and communications would be used during the seismic survey to warn vessels

that are in danger of breaching the exclusion zone. The 500 m safety zone and proposed safe operational limits would be

communicated to key stakeholders well in advance of the proposed seismic survey. Notices to Mariners would also be

communicated through the proper channels.

The proposed exploration activities could potentially impact the fishing industries through:

(i) temporary cessation or displacement of fishing activities within the affected area;

(ii) alteration in the distribution and/or rates of fish catches; or

(iii) interaction of survey equipment with fishing gear.

The commercial fishing sectors that operate within Namibian waters are presented in Section 4 and an assessment of the

significance of the impact of the proposed exploration activities on each sector is given.

1.2.2 ACOUSTIC IMPACTS

In addition to the potential impacts of exclusion to fishing areas, recent research has shown that seismic survey activity may affect

the behaviour and physiology of fish and other marine fauna. Summarised below are some of the main impacts to be considered.

A range of damaging physical effects due to airgun noise have been described for fish, including swim-bladder damage, transient

stunning, short-term stress responses, temporary hearing loss, haemorrhaging, eye damage and blindness . However, studies

have shown that physical damage to fish caused from seismic sources occurs only in the immediate vicinity of the airguns, in

distances of less than a few meters (Gausland 2003).

• Adult and juvenile fish have been shown to display several behavioural responses to seismic sound. These include leaving

the area of the sound source by swimming away and changing depth distribution, changing schooling behaviour and startle

responses to short range start up. These responses could affect spawning behaviour and migration patterns and Dalen et

al. (1996) concluded that the use of seismic airguns be avoided within 50 km of important spawning or migration areas.



• Whilst adult fish can flee from airgun noise, eggs and larvae area unable to do so and therefore may be affected by the

signals. However, it was concluded that the impact of airguns on fish eggs and larvae accounts for an insignificant amount of

mortality compared to the natural mortality rate per day for most fish species at that life stage (Dalen and Mæsted 2008).

• Behavioural responses to seismic sound could lead to decreased catch rates if fish move out of important fishing grounds

(Hirst and Rodhouse 2000). There is little information available on these potential impacts.

2. METHODS

The spatial distribution of catch was mapped at an appropriate resolution for each fishing sector (based on the fishing method and

resulting area covered by fishing gear). The proposed area of operation of the survey vessel was mapped and the spatial overlap

expressed as a percentage of fishing ground available to each sector. This measurement was used as an indication of the

relative extent of the impact on each fishery where an overlap of less than 10% was considered to be local in extent and an

overlap of greater than 10% was considered to be regional in extent (refer to Appendix 1). The average annual catch taken within

the impacted area was used to calculate the amount of catch (also expressed as a percentage of overall total landings) that would

potentially be lost in the event that the fishing sector was excluded from the entire survey area for the full duration of the survey

(i.e. 9-10 months).

In addition to physical exclusion of fishing vessels from a seismic survey area, studies demonstrate that seismic surveys are likely

to lead to a reduction in catch rates not only in the immediate vicinity of the airgun but also in a wider area around it. Estimates of

the distance from the airgun at which a decline in catch rates was observed, the duration of that impact and the magnitude of the

impact (percentage reduction in catch rate) varied considerably between the examples reported. It was therefore decided to

develop a minimum and maximum scenario of potential impact based on a literature review conducted during previous

assessments (Cochrane, 2015 unpublished). The details of each scenario are shown in Table 1.

Table 1: Details of the anticipated minimum and maximum range scenarios used to estimate potential impacts of the noise

generated by the 3D seismic survey on commercial fish catches.

Factor Minimum Zone of Acoustic Disturbance (9 km from source)

Maximum Zone of Acoustic Disturbance (33 km from source)

Radius of impact (km) 9 33

Duration of impact (days) 5 10

Magnitude of impact (% decline in catch) 40 83 (pelagic fisheries)

50 (demersal fisheries)

The area that would be impacted under these different scenarios was estimated by adding the radius of impact to the proposed

area of vessel operation. This resulted in the impact areas shown in Figure 5. The actual catches taken in the impact areas, under

the minimum and maximum case scenarios, were extracted for a period of at least four years, the most recent for which a full

year’s data were available. The average catches for a full year were extracted and summed.

The potential reduction in catches was estimated as:

�� = �� × �� × (��100)

where Ci = catch potentially lost as a result of survey (tonnes)

CT = total catch recorded as taken in the impact area during fishing period (tonnes)

Di = duration of impact (days)

Dt = total days fished during fishing period

Mi = magnitude of impact (%)

The total days fished during the fishing period (Dt) used in these calculations were dependent on the seasonality of each fishery.

For each impact, the INTENSITY (size or degree scale), DURATION (time scale) and EXTENT (spatial scale) were described.

These criteria are used to determine the SIGNIFICANCE of the impact, which is a function of intensity, spatial extent and duration.



The status of an impact was used to describe whether the impact would have a negative, positive or zero effect on the affected

environment Once the significance of an impact had been determined, the likelihood of it occurring was assessed

(PROBABILITY). The CONFIDENCE in the assessment of the significance rating was ascertained using the rating systems

outlined in Appendix 1.

Figure 5: Anticipated impacts areas for the 3D seismic survey derived from the proposed area of vessel operation with the

addition of the impact radius for the expected minimum (9 km) and maximum (33 km) zones of acoustic disturbance (left). The

survey location is shown (right).

3. DATA SOURCES

Namibian commercial fisheries catch and effort data was sourced from MFMR records of commercial fisheries for the years 2000

to 2010 (or to 2013 for the large pelagic long-line and tuna pole sectors)1. The spatial distribution of Namibian fishing pressures

were provided by Steven Holness as part of the spatial biodiversity assessment commissioned by the Benguela Current

Commission (BCC)2. Data on fishing right’s holdings and industrial bodies was sourced from the 2016 edition of the Fishing

Industry Handbook3. Information on species distribution was taken from the Benguela Current Large Marine Ecosystem (BCLME)

Annual State of the Stocks Report 20114. Information on the distribution of Angolan fisheries was compiled from Japp & Wilkinson

(2007), which was based on information obtained from the Angolan Ministry of Fisheries Research (Ministerio das

Pescas)/National Institute of Fisheries Research (INIP) and FAO fisheries statistics website (2014).

1 Updated fisheries catch and effort data was requested from MFMR but not provided in time for this assessment. 2 Holness, S., Wolf, T., Lombard M. and C. Kirchner. 2012. Spatial Biodiversity Assessment and Spatial Management, including Marine Protected Areas: Spatial summary of pressures on marine systems. Benguela Current Commission. 3 Fishing Industry Handbook South Africa, Namibia and Moçambique (2016) 44th edition George Warman Publications, Cape Town, South Africa 4 Benguela Current Large Marine Ecosystem State of Stocks Review 2011 (2nd Edition; Ed C. Kirchner). Benguela Current Commission.



4. DESCRIPTION OF AFFECTED ENVIRONMENT

4.1 OVERVIEW OF NAMIBIAN FISHERIES

The Namibian fishing industry is the country’s second largest export earner of foreign currency and the third largest economic

sector in terms of contribution to the Gross Domestic Product (GDP). In terms of the value of production, Namibia ranks among

the top ten fishing countries globally (Food and Agricultural Organization (FAO): http//www.fao.com.na). Supported by the high

productivity of the Benguela upwelling ecosystem, abundant fish stocks typify Namibian waters. Fish resources in upwelling

systems are typically high in biomass and relatively low in diversity (relative to non-upwelling environments). Commercial fish

stocks, as found in the Benguela system typically support intensive commercial fisheries. Although varying in importance at

different times in history, Namibian fisheries have focused on demersal species, small pelagic species, large migratory pelagic

fish, line-fish (caught both commercially and recreationally) and crustacean resources (e.g. lobster and crabs). Mariculture

production is a developing industry based predominantly in Walvis Bay and Lüderitz Bay and surrounds. The main commercial

fisheries, targeted species and gear types are shown in Table 2 and recent Total Allowable Catches (TACs) are presented in

Table 3 below. The allocation of TACs and management of each fishing sector is the responsibility of MFMR.

Table 2: List of fisheries that operate within Namibian waters, targeted species and gear types used5.

Fishery Gear Type Targeted Species

Mariculture Long-lines, rafts Pacific oysters, European oysters, Black mussel, Seaweed (Gracilaria sp.)

Small pelagic purse-seine Purse-seine Sardine (Sardinops ocellatus), Horse mackerel (Trachurus capensis)

Mid-water trawl Mid-water trawl Horse mackerel (Trachurus capensis)

Demersal trawl Demersal trawl Cape hakes (Merluccius paradoxus, M. capensis), Monkfish (Lophius vomerinus)

Demersal long-line Demersal long-line Cape hakes (Merluccius paradoxus, M. capensis)

Large pelagic long-line Pelagic long-line Albacore tuna (Thunnus alalunga), Yellowfin tuna (T. albacares), Bigeye tuna (T.

obesus), Swordfish (Xiphias gladius) & Shark spp.

Tuna pole Pole and line Albacore tuna

Deep-sea crab Demersal long-line trap Red crab (Chaceon maritae)

Deep-water trawl Demersal trawl Orange roughy (Hoplostethus atlanticus), Alfonsino (Beryx splendens)

Rock Lobster Demersal trap Rock lobster (Jasus lalandii)

Line-fish Hand line Silver kob (Argyrosomus inodorus), Dusky kob (A. coronus)

Table 3: Total Allowable Catches (tons) from 2009/10 to 2015/16 (supplied by Ministry of Fisheries and Marine Resources,

Namibia).

Year Sardine Hake Horse Mackerel Crab Rock Lobster Monk

2009/10 17 000 149 000 230 000 2700 350 8 500

2010/11 25 000 140 000 247 000 2700 275 9 000

2011/12 25 000 180 000 310 000 2850 350 13 000

2012/13 31 000 170 000 310 000 3100 350 14 000

2013/14 25 000 140 000 350 000 3100 350 10 000

2014/15 25 000 210 000 350 000 3150 300 12 000

2015/16 15 000 140 000 335 000 3446 250 10 000

Note: Deepwater trawl TAC is currently not applied for Alfonsino and Orange roughy. There is no TAC (output control) for albacore tuna – this is

an effort (input) controlled sector with no restriction on catch.

5 Refer to MFMR Web site http://www.mfmr.gov.na/ Note that this web site does not provide the most recent information and Capricorn Marine Environmental uses direct communication with researchers and the fishing industry for updates on catch and effort, vessel lists and allowable catches. Refer also to the 2016 Fishing Industry Handbook (Namibian Sector) 44th Edition George Warman Publications, Rondebosch, Cape Town.



Fishing Ports

Namibia has only two major fishing ports from which all the main commercial fishing operations are based namely, Walvis Bay

and Lüderitz. In central Namibia, the major port is Walvis Bay and it is from here that the majority of fishing vessels operate. Most

of the fishing conducted from this port is, for economic and logistical reasons, directed at fishing grounds in the central and

northern part of Namibia and to a lesser extent the southerly fishing grounds towards the South African border. A significant

amount of fishing activity also takes place from Lüderitz, from where hake trawlers and long-liners operate as well as a small rock

lobster fishery based in southern Namibian waters.

Fleet Capacity

There are currently 116 Namibian-registered commercial fishing vessels, of which 16 are currently active within the rock lobster

sector6. The dominant fleet comprises demersal trawlers that include both large freezer vessels (up to 70 m in length) as well as a

smaller fleet of monk trawlers. These vessels fish year round, with the exception of a one month closed season in October, and

range the length of the Namibian Exclusive Economic Zone (EEZ). There is a 200 m fishing depth restriction (i.e. no bottom

trawling permitted shallower than 200 m). Prior to Namibian independence in 1990, a much larger fleet of trawlers existed,

however Namibia now exercises strict effort control and vessel size limits. The only other fleets of significance are the mid-water

trawlers that target horse mackerel and the large pelagic tuna vessels. The mid-water fleet was historically uncontrolled and

comprised of many large industrial vessels mostly of eastern origin (Ukranian and Russian). Currently these large vessels

(mostly >100 m in length) operate in the northern waters of Namibia and are restricted to fewer than 20 vessels. The large pelagic

(tunas and shark) vessels operate extensively in Namibian waters, concentrating in the south near the South African border when

the migrations of albacore and yellowfin tuna pass through. The numbers of these vessels varies frequently and is dependent on

the availability of fish. The tuna pole (baitboat) vessels are a small fleet and also increase in numbers depending on the number

of licenses issued to South African boats. The tuna long-liners are also variable with the number of licenses issued to both

Namibian flags and others (mostly Asian) fluctuating annually. The extent and number of these vessels is difficult to ascertain (as

they are unpublished), although the actual numbers are limited and are less than the numbers of licensed Namibian boats.

There are few known foreign fishing vessels licensed to fish in Namibian waters although the majority of the current mid-water

fleet have permits to fish under foreign flag registration, but as a rule all licensed fishers must reflag under Namibia. There is a

possibility that licenses may have been issued to foreign tuna boats although these would be few in number and they would be

closely monitored by the Namibian compliance units and their Vessel Monitoring System (VMS).

Research Surveys

MFMR conducts regular research (biomass) surveys for demersal, mid-water and small pelagic species. These surveys are

normally fixed at specific times of the year and cover the entire continental shelf from the Angolan to the South African maritime

borders. For example the demersal trawl surveys take place in January – February over the period of one month. In some years

the Benguela Current Commission may conduct “transboundary” surveys. MFMR surveys normally follow fixed transects form

inshore to offshore. Surveys have a systematic transect design, with a semi-random distribution of stations along transects.

Stations within transects are selected in such a way that each 100-m bottom depth range is sampled at least once. Transects run

perpendicular to the coastline, and area spaced between 20 and 25 nm apart, with transect lengths ranging from 20 to 80 nm.

Most of the hauls take place during daylight hours.

4.2 OVERVIEW OF ANGOLAN FISHERIES

The fisheries sector represents about 1.7% of the GDP of Angola, ranked second in importance to the national economy after oil

and mining (FAO, 2012). The Angola current with its warm water from the north and the cold Benguela Current in the south

creates a strong upwelling with a high productive ecosystem for marine resources. With an EEZ of 495 862 km2, the area from

Lobito to the mouth of the Cunene River, also known as the Southern fishing zone is the most productive of Angola’s fishing

zones, with an abundance of horse mackerel, sardinellas and sardine, tunas and a range of demersal species including hake.

The Central fishing zone stretches from Luanda to Benguela and yields mainly sardinellas, horse mackerel and demersal species.

The Northern fishing zone extends from Luanda to Cabinda and has a large density of horse mackerel and sardinellas and a

smaller proportion of demersal species. Tunas are caught at certain times of the year whilst some marine shrimp are also

6 The number of vessels active within the rock lobster sector has ranged between 16 and 29 per season over the last five years (2010/11 to 2015/16) (E. Maletzki pers. com.)



harvested from the Angolan waters. In 2012, the overall production from marine fisheries was estimated at about 277 000 tonnes,

of which the catch of small pelagic species represented about half. Angolan fisheries are separated into industrial and semi-

industrial sectors (responsible for about half of total marine catches) and artisanal fisheries. The responsibility for fisheries

management lies with the Ministry of Fisheries (Ministério das Pescas). The main commercial fisheries, targeted species and

gear types are shown in Table 2 below.

Table 4: List of fisheries that operate within the Angolan marine environment, targeted species and gear types used (Source,

FAO).

Group Gear Type Targeted Species Distribution area Number of

Vessels

Pelagic

Industrial purse

seiners

Sardinella (Sardinella aurita and S. maderensis), Cape

horse mackerel (Trachurus capensis) and Cunene horse

mackerel (T.trecae)

Whole coast (5°S-17°15´S) but

mostly centre (9°05´S-13°S) and

north (5°S-9°15´S)

26

Semi-industrial

purse seiners

Sardinella, Cape horse mackerel and Cunene horse

mackerel

Whole coast (5°S-17°15´S) but

mostly centre (9°05´S-13°S) and

north (5°S-9°15´S)

43

Longline

Tuna and tuna-like species including yellowfin tuna

(Thunnus albacares) and skipjack tuna (Katsuwonus

pelamis)

Whole coast (5°S-17°15´S) 16

Demersal Trawl

Hake (Merluccius polli and M. capensis), Dentex spp.

(D. macrophthalmus, D. angolensis, Epinephelus spp,

Pseudotolithus typus and P. senegalensis)

Whole coast (5°S-17°15´S) 40

Gillnet Sparidae, Scianidae, Merllucidae Whole coast (5°S-17°15´S) 7

Crustaceans

Trawl Deepwater rose shrimp (Parapenaeus longirostris) and

striped red shrimp (Aristeus varidensis)

Centre (9°05´S-13°S) 23

Trap Crab (Chaceon maritae) Centre (9°05´S-13°S) and south

(13°S-17°15´S)

4

Angolan fisheries can be divided in terms of their commercial application viz.

� Subsistence : Non-commercial – Catch intended for family consumption, occasional surplus is allowed to be sold

� Artisanal : Commercial -· Vessel up to 14 m in length, propulsion system: paddles, sail, onboard and outboard engine.

Fishing gear: hand lines, gill nets, entangling nets.

� Semi-industrial : Commercial – Vessel up to 20 m in length. Propulsion system: inboard engine. Fishing gear: mechanical

trawling, hand lines, drifting longlines, entangling nets, seine nets and others. On-board refrigeration: ice on board

� Industrial : Commercial (either catch-specific species with a high commercial value, or large quantities of fish with a lower

commercial value). Vessel over 20 meters long. Propulsion system: engine. Fishing gear: mechanical. On-board

refrigeration: ice and other processing methods on board. Vessel length is one of several criteria determining its industrial/

semi-industrial status.

Artisanal sector

There is a large marine artisanal fishing fleet in Angola. In 2010 about 100 000 people earned their living in the fishery sector, half

of which were active in the artisanal sector. According to survey data from the Institute for the Development of Artisanal Fisheries

and Aquaculture (IPA), total artisanal catches in 2010 exceeded 102 000 tonnes. Artisanal fishers catch groupers, snappers,

seabreams, croakers, spiny lobster and lower-value species. The fishers are organized into groups which generally own one or

more boats, nets or sails. Members of the group go fishing together and divide the catch, which is either dried or salted, or sold

fresh to urban markets. Artisanal fishing activities are carried out from about 190 landing sites scattered along the coast.

Benguela and Luanda provinces have the greatest concentration of artisanal fishing. Support centres for the artisanal sector are

located in each province (Cabinda, Zaire, Bengo, Luanda, Kwanza Sul, Benguela and Namibe). Each support centre has

separate areas for (i) administration; ii) maintentance of vessels and gear; (iii) handling and cooling fish; and, facilities for

disembarking. The centres in Benguela and Namibe also have small jetties. The state provides fuel subsidies to artisanal and

small-scale fisheries. Between 3000 and 5500 boats are estimated to be active within this sector. The artisanal sector is limited in



operational distance from the shore and are given exclusive use to 3 nm from the shore i.e. no other industrial fishing is permitted

in this area.

Industrial sector

Industrial-scale fishing is carried out mainly by foreign vessels leased to, or in joint venture with, Angolan enterprises. Foreign

vessels known to fish in Angolan waters are from China, Japan, South Korea, Nigeria, Russia, Spain and Namibia. Industrial

fisheries including about 150 vessels land pelagic fish (horse mackerel, sardinella, tuna), shrimp, deep sea red crab, lobster and a

variety of demersal fish. Purse-seining is the most common industrial fishing technique employed. Overfishing and changes in

hydrological conditions have strongly reduced the fishing potential for industrial fisheries. The resource assessment carried out in

2010 showed that a major portion of small pelagic species, the sardinellas, were under-utilized while horse mackerel stocks were

overexploited and required immediate intervention in the form of effective resource management measures (FAO 2014). There is

an established Monitoring, Control and Surveillance (MCS) structure in place which includes modern VMS.

Fishing Ports

Industrial and semi-industrial fishing vessels unload fish and take on board supplies at Luanda, Kwanza Sul, Benguela and

Namibe. The vessels choose where to land depending on the expected fish price. Generally, about 70 % of the fish catch landed

by the industrial fleet is landed in Luanda. Many marine artisanal fishers do not have a fixed place for disembarking catches. This

is due to the fact that fishers, and their communities, follow the fish along the coast, and most artisanal craft can be brought

ashore anywhere on the sandy beaches. IPA has selected 65 localities, in seven coastal provinces for data collection, out of the

190 localities recorded as main landing centres (FAO, 2014).

4.3 STOCK DISTRIBUTION, SPAWNING AND RECRUITMENT

The distribution patterns of fish stocks on which Namibian commercial fisheries are based, are summarised as follows:

� The sardine stock ranges along the entire Namibian coast,

but in recent years predominantly from 25ºS northwards to

southern Angola, inshore of the 200 m isobath. This fishery

collapsed in the 1960s and currently the fishery status

remains overexploited with a limited distribution pattern. The

southern border of this range is demarcated by the Lüderitz

upwelling front, a region of cold, upwelled water located off

the port of Lüderitz. Historically, spawning occurred

continuously from September to April with two seasonal

peaks evident. The first from October to December in an

inshore area between Walvis Bay and Palgrave Point and

the second from February to March near the 200 m isobath

between Palgrave Point and Cape Frio (King, 1977).

Spawning in the north was predominantly by young adults

and peaked in late summer and autumn. In contrast, older

fish spawned further south in summer, in cooler waters close

to upwelling zones. Following spawning, larvae drifted

southward along the coast. Sardine would then migrate

northwards where juveniles and young adults would spawn

for the first time. Adult fish would subsequently return to

south to spawn off Walvis Bay (Boyer and Hampton 2001a).

Since the collapse of the sardine stock, spawning in the

south has decreased (Crawford et al. 1987 in Boyer &

Hampton, 2001) as the migration of sardine has contracted

(Boyer and Hampton 2001a). Spawning now peaks 30–80

km off the central Namibian shelf (Hutchings et al., 2002)

between September and October.

Figure 6: Distribution of Cape horse mackerel (D’Almeida 2007).



� Horse mackerel occurs predominantly north of 25ºS with juveniles present inshore of the 200 m isobath and adult

populations extending up to the 1 000 m isobath. Biomass estimates are usually low in summer and higher during winter

and early spring (higher fishing catch rates are expected during the months June to November). Horse mackerel in the

northern Benguela system spawn throughout the year, with a peak in spawning activity occurring during late summer and

autumn. The spawning area is located from Conception Bay to the Angola-Benguela front and nursery grounds exist

inshore of these spawning grounds (see Figure 6). Results from recent ichthyoplankton studies by the R.V Dr Fridtjof

Nansen and R.V. Welwitchia found a continuous distribution of eggs inshore from the Walvis Bay area to the Cunene River

with highest concentrations between the Cunene River and Möwe Bay. Juveniles migrate south to Walvis Bay especially in

winter and maturing fish then move offshore and migrate north to spawn (Boyer and Hampton 2001a).

� Albacore tuna, yellowfin tuna, bigeye tuna, shark and swordfish are large pelagic species with an extensive offshore

distribution ranging along the entire Namibian coastline. Yellowfin tuna are distributed between 10ºS and 40ºS in the south

Atlantic, and spawn in the central Atlantic off Brazil in the austral summer (Penney et al. 1992). According to Crawford et al.

(1987) juvenile and immature yellowfin tuna occur throughout the year in the Benguela system. After reaching sexual

maturity they migrate (in summer) from feeding grounds off the West Coast of southern Africa to the spawning grounds in

the central Atlantic. Bigeye tuna occurs in the Atlantic between 45ºN and 45ºS. Spawning takes place in the Gulf of Guinea

and in the eastern central Atlantic north of 5ºN and it is thought that bigeye tuna migrate to the Benguela system to feed.

Swordfish spawn in warm tropical and subtropical waters and migrate to colder temperate waters during summer and

autumn months.

� Hake (two species) is the most commercially important Namibian fishery. Within the Namibian EEZ the hake stock extends

along the entire shelf and slope between the 100 m and 1 000 m isobaths. Hake spawn and recruit throughout the year with

peaks in spawning thought to occur in early summer (Botha 1980, Olivar et al. 1988) along the shelf break off central

Namibia. While temporal and spatial patterns in hake spawning are yet to be fully resolved (Smith and Japp 2009),

spawning by M. capensis has been recorded along most of the Namibian coast from about 27°S to 18°S (Olivar and

Shelton, 1993). While spawning occurs across a wide range, areas of localised spawning appear to be focused off central

Namibia (25°S to 20°S), although the exact location varies between years (Assorov and Berenbeim 1983 cited in Sundby et

al. 2001, Olivar et al. 1988, Sundby et al. 2001). Fishing effort is relatively constant throughout the year except for a closure

for the month of October and relatively lower levels of effort expended during November and December.

� Monkfish (two species) is found along the entire extent of the Namibian coast, with the fishery concentrated between

17º15'S and 29º30'S at depths of 200 m to 500 m. Spawning is irregular and variable and is thought to occur throughout the

year (Macpherson 1985) with two separate areas of recruitment between the 100 m and 300 m isobaths off Walvis Bay and

Lüderitz (Leslie and Grant 1990).

� Deep-sea red crab stocks are distributed predominantly from 23º35'S northwards into Angola within a depth range of

approximately 300 m to 1 000 m. Spawning takes place throughout the year (Le Roux 1997) on the shallower waters of the

continental slope with adult females generally occurring at shallower depths to that of males.

� Orange roughy has a discontinuous pattern of distribution along the Namibian continental slope with dense aggregations

of stock within four known spawning grounds (or Quota Management Areas). The species has a short, intense spawning

period of about a month from July to August (Boyer and Hampton 2001). Fishable aggregations are usually found on hard

grounds on features such as seamounts, drop-off features or canyons (Branch, 2001). Off Namibia this species has a

restricted spawning period of less than a month in late July, when spawning takes place in dense aggregations close to the

seafloor in small areas typically between 10 and 100 km2 in extent (Boyer and Hampton 2001b).

� Rock lobster occurs from Cape Cross to the east coast of South Africa; however, significant densities only occur south of

Meob Bay (Cockcroft 2001) from 25ºS to 28º30'S in water depths shallower than 100 m. The spawning cycle of this species

is strongly related to its annual moulting cycle. Males moult in spring and mating takes place after the females have moulted

in late autumn and early winter (Boyer and Hampton 2001a). Females carry their eggs until they hatch in October and

November, releasing planktonic larvae (Pollock 1986). These larvae remain in the plankton for a period of months before

becoming free-swimming (Crawford et al. 1987) and settling in near-shore rocky areas. Adults generally occur further

offshore than juveniles, except in central Namibia where the whole population is forced close to the shore by low-oxygen

conditions (Pollock and Beyers 1981).



The principle commercial fish species in

Namibia undergo a critical migration pattern

which is central to the sustainability of the

small pelagic and hake fisheries. In Namibian

waters, hake spawning commences north of

the powerful Lüderitz upwelling centre (27°S)

and continues up to the Angola–Benguela

Front (16–19°S). Sardines and horse

mackerel also spawn in the region between

Lüderitz and the Angola–Benguela front (see

Figure 7). Circulation patterns at depth reveal

complex eddying and considerable southward

and onshore transport beneath the general

surface drift to the north-west (Sundby et al.

2001). As eggs drift, hatching takes place

followed by larval development. Settlement of

larvae occurs in the inshore areas. Sardine

spawning peaks 30–80 km offshore during

September–October off the central Namibian

shelf, with larvae occurring slightly further

offshore and recruits appearing close inshore,

so there appears to be a simple inshore–

offshore movement over the Namibian shelf.

Spawning also occurs in mid-summer in the

vicinity of the Angola–Benguela Front

(Crawford et al. 1987).

During late summer (December – March)

warm water from the Angolan Current pushes

southwards into central Namibian waters, allowing pelagic spawning products to be brought into the nursery grounds off central

Namibia. There is a high likelihood of substantial offshore transport associated with this convergent frontal region (Shannon

1985).

4.4 SMALL PELAGIC PURSE-SEINE

The pelagic purse-seine fishery is based on the Namibian stock of Benguela sardine (Sardinops ocellatus) (also regionally

referred to as pilchard), and small quantities of juvenile horse mackerel. Commencing in 1947, the sardine fishery was the largest

by volume of fish landings in the Benguela ecosystem and was based from the port of Walvis Bay. The fishery grew rapidly until

1968 at which time the stock collapsed due primarily to overfishing. Fishing continued thereafter at a low level of effort, but the

resource has not fully recovered. Since independence, Namibia has issued a small TAC of sardine to sustain the small pelagic

sector and to allow land-based factory turnover. In addition they allow part of this catch to target juvenile horse mackerel.

However in recent years the resource base has been unable to sustain even these minimal TACs and the fishery has been closed

and reopened on an ad hoc basis depending on resource availability. The fishery is currently open with a TAC (2016) of 14 000 t

for sardine. Recent TACs are shown in Figure 8.

Figure 7: Schematic diagram of general fish spawning and nursery

areas off Namibia (after Hutchings et al., 2002).



Figure 8: Total Allowable Catch (TAC) of sardine for the years 1991

to 2016 (Source: MFMR).

Figure 9: Typical gear configuration of a pelagic

purse-seine vessel targeting small pelagic species

(Source: http://www.fao.org).

The small pelagic fleet consists of 36 wooden, glass-reinforced plastic and steel-hulled vessels ranging in length from 21 m to

48 m. The targeted species are surface-shoaling and once a shoal has been located the vessel will steam around it and encircle it

with a large net, extending to a depth of 60 to 90 m (see Figure 9). Netting walls surround aggregated fish, preventing them from

escaping by diving downwards. These are surface nets framed by lines: a float line on top and lead line at the bottom. Once the

shoal has been encircled the net is pursed, hauled in and the fish pumped on board into the hold of the vessel. It is important to

note that after the net is deployed the vessel has no ability to manoeuvre until the net has been fully recovered on board and this

may take up to 1.5 hours. Vessels usually operate overnight and return to offload their catch the following day.

The current extent of the stock distribution has effectively contracted since stock collapse, prior to which the historical distribution

was throughout the Benguela system. Recent biomass surveys have shown small aggregations of the stock mostly located

inshore of the 200 m isobath. The distribution of small pelagic purse-seine fishing grounds within Namibian waters and in relation

to the proposed survey area is shown in Figure 10. Fishing occurs primarily Northwards of Walvis Bay but extends to the Angolan

border, inshore of the 200 m isobath.

The proposed area of operation (which does not include the maximum zone of disturbance) covers approximately 489 km2 or

0.7% of the ground used by the small pelagic purse-seine fishery. Further effort is expended inshore of the proposed survey area,

adjacent to the coastline. Average annual catch within the area of operation amounts to approximately 0.2% of the total catch

landed nationally. The reduction in catch due to the influence of the acoustic signal beyond the survey area would be expected to

result in a reduction in catch of up to 0.2 tonnes per day at a distance of up to 33 km from the acoustic source. Thus the total loss

over the 10 month survey is estimated to be in the order of 7.3 tonnes. It is important to note that this is an over estimate as

fishing would be able continue in other areas, and overall catch may not in fact be reduced. The impact of the proposed survey

on the small pelagic purse-seine fishery is likely to be of local extent and short-term duration. Based on the low risk of

encountering fishing vessels within the survey area and that fishing operations would be able to continue, albeit in a modified

way, the intensity of the impact is considered to be medium. The overall significance of the impact is considered to be very low

and the likelihood of the impact occurring is improbable. The degree of confidence in the assessment is high.

The purse-seine industry for small pelagic species is the largest of the Angolan fisheries with respect to landings, targeting juvenile Cunene

horse mackerel, with a varying by-catch of Cape horse mackerel, round sardinella and Madeiran sardinella. The fishery is predominantly

active within northern and central fishing grounds and is not expected to be active in the Namibe province. The Angolan purse-seine fishery

is therefore not expected to be impacted by the proposed survey.

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Figure 10: Spatial distribution of small pelagic purse-seine catch (1996 – 2011) in the vicinity of the proposed survey.

Impacts on the small pelagic purse-seine fishing industry

Extent Intensity Duration Probability Significance Status Confidence

Without

mitigation Local Medium Short-term Improbable VERY LOW – ve High

Mitigation measures:

• Prior notification of survey commencement.

• Radio Navigational Warnings.

• At sea communications to maintain adequate safety clearance between fishing vessels and survey operation.

With

mitigation Local Medium Short-term Improbable VERY LOW – ve High



4.5 MID-WATER TRAWL

The distribution of horse mackerel (Trachurus capensis) within Namibian waters ranges generally between water depths of 200 m

to 1000 m (Crawford et al. 1987). Horse mackerel in the northern Benguela system spawn throughout the year, with a peak in

spawning activity occurring during late summer and autumn. The spawning area is from Conception Bay to the Angola-Benguela

front. Nursery grounds exist adjacent to these spawning grounds but closer to shore.

Horse mackerel has the highest volume and catch of all Namibian fish stocks; however by economic value is the second highest

contributor to the fishing industry behind the Cape hake fisheries. The TAC for horse mackerel was set at 350 000 t in 2013.

Horse mackerel are either converted to fishmeal or sold as frozen, whole product with landings for the year 2006 valued at N$800

million (MFMR unpublished data in Kirchner et al., 2010). The TACs set from 1991 to 2016 for the pelagic and mid-water fisheries

targeting the Namibian stock of horse mackerel are shown in Figure 11.

Figure 11: TACs set for the mid-water fishery for the Namibian stock of Cape horse mackerel from 1991 to 2016

In 2013, 67 rights-holders were registered within the mid-water trawl fishery, with the duration of rights ranging from seven to 15

years. Of these, 12 companies have been in the industry a number of years. New right’s holders have been combined into 11 joint

ventures, some of which have leased their quota to old right’s holders; therefore, there are currently (2013) nine fishing operators

in the sector. Sixteen vessels are licenced to trawl for horse-mackerel in Namibia. Of these, only one is Namibian-flagged,

although a further eight are based permanently in Namibia. Vessels range in length between 60 m and 120 m.

The stock is caught by the mid-water trawl fishery (targeting adult horse mackerel) and small pelagic purse-seine fishery (smaller

quantities of juvenile horse mackerel). The target catch species is meso-pelagic (i.e. found at depths between 200 m and 1000 m

above the sea floor) and shoals migrate vertically upwards through the water column between dusk and dawn. Mid-water

trawlers exploit this behaviour (diurnal vertical migration) by adjusting the depth at which the net is towed (this typically varies

from 400 m to just below the water surface). The net itself does not come into contact with the seafloor (unlike demersal trawl

gear) and towing speed is greater than that of demersal trawlers (between 4.8 and 6.8 knots). Trawl warps are heavy, ranging

from 32 mm to 38 mm in diameter. Net openings range from 40 m to 80 m in height and up to 120 m in width (see Figure 12).

Weights in front of, and along the ground-rope assist in maintaining the vertical opening of the trawl. To reduce the resistance of

the gear and achieve a large opening, the front part of the trawl net is usually made from very large rhombic or hexagonal

meshes. The use of nearly parallel ropes instead of meshes in the front part is also a common design. On modern, large mid-

water trawls, approximately three quarters of the length of the trawl is made with mesh sizes above 400 mm. The fishery operates

year-round with relatively constant catch and effort values by month (see Figure 13).

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acke

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'000

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)

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Figure 12: Typical gear configuration used during mid-water trawling operations.

Figure 13: Average monthly catch (tons) and effort (hours) expended by the Namibian mid-water trawl fishey.

The mid-water trawl fleet operates exclusively out of the port of Walvis Bay and fishing grounds extend north of 25ºS to the border

of Angola. Juvenile Cape horse mackerel move into deeper water when mature and are fished mostly between the 200 m and

500 m isobaths towards the shelf break. The distribution of horse mackerel-directed fishing grounds in relation to the proposed

survey area is shown in Figure 14. Based on commercial fishing records, trawling activity would be expected within the proposed

survey area between the 200 m and 1000 m isobaths. The proposed survey (which excludes the maximum zone of disturbance)

covers approximately 5 787 km2 or 17.3% of the total trawlable ground available to the sector. Annual effort expended within the

survey area amounts to approximately 3 553 fishing hours (22.9% of the total) and catch taken amounts to 32 194 tonnes (17.1%

of the total). Effort within the survey area is variable, with no clear seasonal trend (see Figure 15). The reduction in catch due to

the influence of the acoustic signal beyond the survey area would be expected to result in a reduction in catch of up to 2.7 tonnes

per day at a distance of up to 33 km from the acoustic source. Thus the total loss over the 10 month survey is estimated to be in

the order of 810 tonnes. It is important to note that this is an over estimate as fishing would be able continue in other areas, and

overall catch may not in fact be reduced.

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Figure 14: Spatial distribution of horse mackerel mid-water trawl catch (1997 – 2011) along the Namibian coastline and in the

vicinity of the proposed survey.

The impact of the proposed survey on the mid-water trawl fishery is likely to be of regional extent and short-term duration. The

impact is expected to be of high intensity (fishing operations in the survey area are likely to be altered to the extent that they

would temporarily cease). The overall significance of the impact is assessed to be medium and the likelihood of the impact

occurring is highly probable. The termination of surveying during the key cetacean migration and breeding period from the

beginning of June until the end of November would help mitigate this impact to a certain extent, as the months of highest fishing

activity in the survey area are June and July (see Figure 15)

Figure 15: Monthly catch (horse mackerel) taken from the proposed survey area versus total catch (horse mackerel) landed.

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In Angolan waters, adult horse mackerel is targeted by the pelagic trawl fleet which comprises large steel, mid-water stern trawlers. Catch

reports suggest that fishing effort is highest in northern and central Angolan waters and that the fishery is not active in the Namibe province

or in the vicinity of the proposed survey area.

Impacts on the mid-water trawl fishing industry


Without

mitigation Regional High Short-term

Highly

probable MEDIUM – ve High





With


Highly

probable MEDIUM – ve High

4.6 DEMERSAL TRAWL

A fleet of 71 demersal trawlers are currently licensed to operate within the fishery. Their principal target species are hake

(Merluccius capensis and M. paradoxus), caught in deeper waters (trawling is not permitted in less than 200 m depth). Smaller

trawlers fish inshore for monkfish (Lophius spp.), sole and kingklip. 18 demersal long-liners (19-55 m length range) also target

hake, with smaller quantities of highly valuable kingklip (Genypterus capensis) and snoek (Thyrsites atun). The directed hake

trawl fishery is Namibia’s most valuable fishery with a current annual hake TAC of 140 000 t (2015/16) – recent TACs for hake

and monkfish are shown in Figure 16. The fishery is active year-round except for a closed period during October each year.

Figure 16: Total Allowable Catch set for Hake and Monkfish from 1991 to 2016.

The deep-sea fleet is divided into wet-fish and freezer vessels (70:30 ratio is prescribed) which differ in terms of the capacity for

the processing of fish offshore (freezers process at sea and wet-fish vessel land fish at factories ashore for processing) and in

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terms of vessel size and capacity (shaft power of 750 – 3 000 kW). Wet-fish vessels have an average length of 45 m, are

generally smaller than freezer vessels which may be up to 90 m in length. Whilst freezer vessels may work in an area for up to a

month at a time, wet-fish vessels may only remain in an area for about a week before returning to port (catch is retained on ice).

The majority of trawlers operate from the port of Walvis Bay, with fewer vessel operating from Lüderitz.

Trawl gear configurations are similar for both freezer and wet-fish vessels, the main elements of which are trawl warps, bridles

and doors, a footrope, headrope, net and codend (see Figure 17). Generally, trawlers tow their gear at 3.5 knots for up to four

hours per drag. When towing gear, the distance of the trawl net from the vessel is usually between two and three times the depth

of the water. The horizontal net opening may be up to 50 m in width and 10 m in height. The swept area on the seabed between

the doors may be up to 150 m. The opening of the net is maintained by the vertical spread of the trawl doors, which are in contact

with the seafloor.

Typical demersal trawl gear configuration consists of:

i. Steel warps up to 32 mm diameter - in pairs up to 3km long when towed;

ii. A pair of trawl doors (500kg to 3t each);

iii. Net footropes which may have heavy steel bobbins attached (up to 24" diameter) as well as large rubber rollers (“rock-

hoppers”); and

iv. Net mesh (diamond or square shape) is normally wide at the net opening whereas the bottom end of the net (or cod-end)

has a 130 mm stretched mesh.

Figure 17: Schematic diagram of trawl gear typically used by deep-sea demersal trawl vessels (Source: http://www.fao.org).

While temporal and spatial patterns in hake spawning are yet to be fully resolved (Smith and Japp 2009), spawning by M.

capensis has been recorded along most of the Namibian coast from about 27°S to 18°S (Olivar and Shelton, 1993). While

spawning occurs across a wide range, areas of localised spawning appear to be focused off central Namibia (25°S to 20°S),

although the exact location varies between years (Assorov and Berenbeim 1983 cited in Sundby et al. 2001, Olivar et al. 1988,

Sundby et al. 2001). Fishing effort is relatively constant throughout the year except for a closure for the month of October and

relatively lower levels of effort expended during November and December (see Figure 18).

Codend

Trawl warps (steelwire rope)

Trawl net

Headrope

Doors (<3000kg) Spread 100m+



Figure 18: Number of trawls expended on a monthly basis by the demersal trawl fleet both nationally and within the proposed

survey area.

Fishing grounds extend along the entire coastline following the distribution of hake and monkfish along the continental shelf at a

depth range of 200 m7 to 850 m (see Figure 19). Based on commercial fishing records, trawling activity would be expected within

the proposed survey area between the 250 m and 600 m isobaths. The proposed survey area covers approximately 2 921 km2 or

3.5% of the total trawlable ground available to the sector. Annual effort expended within the survey area amounts to

approximately 3 598 fishing hours (2.4% of the total) and catch taken amounts to 3 538 tons (3.7% of the total). The reduction in

catch due to the influence of the acoustic signal beyond the survey area would be expected to result in a reduction in hake and

monkfish catch of up to 0.1 tonne per day. Thus the total loss over the 10 month survey is estimated to be in the order of 30

tonnes. It is important to note that this is an over estimate as fishing would be able continue in other areas, and overall catch may

not in fact be reduced.

Figure 19: Spatial distribution of the catch of hake (1992 – 2010) in the vicinity of the proposed survey.

7 Demersal trawlers are prohibited from operating in waters shallower than 200 m.

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The impact of the proposed survey on the demersal trawl fishery is likely to be of local extent and short-term duration. The impact

is expected to be of medium to high intensity. The overall significance of the impact is assessed to be low and the likelihood of

the impact occurring is highly probable. The impact on the demersal trawl fishery could be reduced by timing the survey to

coincide with a period of no fishing during the month of October, and periods of relatively low fishing effort during November and

December. To a large extent this would be achieved by the period of closure to seismic surveying between June and November

(as mitigation against potential impacts on cetaceans during their annual migration period).

The Angolan demersal trawl fisheries fall into two major groups, those targeting demersal finfish (active along the entire coastline) and

those targeting demersal prawns and shrimps (active in the northern and central fishing zones). The majority of landings by the demersal

trawl fishery targeting finfish (hake and seabreams) are recorded in the province of Luanda with less than 1% recorded in the southern

province of Namibe. It is probable that demersal trawl vessels would be encountered in Angolan waters if the survey vessel enters Angolan

waters in the vicinity of the proposed survey area.

Impacts on the demersal trawl fishing industry


Without

mitigation Local

Medium to

High Short-term

Highly

probable LOW – ve High





With

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probable LOW – ve High

4.7 DEEP-WATER TRAWL

The deep-water trawl fishery is a small but lucrative fishing sector directed at the outer Namibian shelf from 400 m to 1500 m

water depth targeting orange roughy (Hoplostethus atlanticus) and alfonsino (Beryx splendens). The species is extremely long-

lived (>100 years) and aggregates densely, leading to high catch rates. Spawning aggregations of orange roughy occur between

June and August. Fishable aggregations are usually found on hard grounds on features such as seamounts, drop-off features or

canyons (Branch, 2001). Off Namibia this species has a restricted spawning period of less than a month in late July, when

spawning takes place in dense aggregations close to the bottom in small areas typically between 10 and 100 km2 in extent (Boyer

and Hampton 2001b). The fishery uses a similar gear configuration to that used by the demersal hake-directed trawl fishery.

Fishing grounds were discovered in 1995/1996 and total catches reached 15 500 t in 1997. At this point catch limits were set (see

Figure 20) and effort was limited to five vessels. Following a drop in the biomass levels, TACs were decreased from 12 000 t in

1998 to 1875 t in 2000. The fishery has been closed since 2007.

Figure 20: TACs issued for orange roughy (H. atlanticus) and alfonsino (B. splendens), targeted by the deep-water trawl fishery.

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In Namibia the orange roughy fishery is split into four Quota Management Areas (QMA’s) referred to as “Hotspot”, “Rix”,

“Frankies” and “Johnies” and TACs are set for each specific QMA. Almost no fishing for this species takes place outside of the

designated QMAs. Figure 21 shows the spatial distribution of fishing grounds and QMAs in the vicinity of the proposed survey

area. Although there is an overlap between the proposed survey area and fishing grounds, the sector is currently closed and

there is therefore no impact expected on the deep-water trawl fishery. There is no deep-water trawl sector active in Angolan

waters.

Figure 21: Spatial distribution of catch positions and QMAs of the deep-water trawl fishery targeting orange roughy (1994 to

2007). Note that the fishery is currently closed.

4.8 DEEP-SEA CRAB

The Namibian deep-sea crab fishery is based on two species of crab namely spider crab (Lithodes ferox) and red crab (Chaceon

maritae). The fishery commenced in 1973 with a peak in catches of 10 000 t in 1983. Catches remained high during the 1980s

between 5000 t and 7000 t. Following heavy exploitation by foreign fleets during this period, catch rates dropped significantly to

2000 t in 1997 and have been steadily increasing since then. The TAC for 2016 has been set at 3446 t (see Figure 22).

Method of capture involves the setting of a demersal long-line with a string of approximately 400 Japanese-style traps (otherwise

known as “pots”) attached to each line. Traps are made of plastic and dimensions are approximately 1.5 m width at the base and

0.7 m in height. They are spaced 15 m apart and typically baited with horse mackerel or skipjack. The line is typically 6000 m to

7000 m in length and weighted at each end by a steel anchor. A surface buoy and radar reflector mark each end of the line via a

connecting dropper line that allows retrieval of the gear. Up to 1200 traps may be set each day (or two to three lines) and are left

to soak for 24 to 120 hours before being retrieved. Schematic diagrams of the types of gear used within the fishery are shown in

Figure 23.



Figure 22: TACs set for red crab (C. maritae) from 1991 to 2016.

Figure 23: Schematic diagram of the gear configuration used within the deep-sea crab fishery.

The distribution of red crab extends from ~5°S to just South of Walvis Bay at a depth range of 300 m to 1000 m (see Figure 24),

but the highest concentrations are found in the north-eastern extent of its distribution. Fishing grounds extend between the 400 m

and 1000 m isobaths (there is a minimum operational depth of 400 m set for the fishery). The fishery is small, with four vessels

currently operating from the port of Walvis Bay. Vessels are active year-round.

The proposed survey area (excluding zones of acoustic disturbance) covers approximately 2 932 km2 or 14.7% of the total ground

fished by the sector. Annual effort expended within the survey area amounts to approximately 14.2% of the total effort expended

by the fishery and catch taken within the area amounts to approximately 15% of total landings. Based on current research

findings, there are no anticipated effects of seismic noise on the catchability of crustaceans therefore the impact of the survey on

the crab trap fishery relates to physical exclusion from fishing grounds rather than any significant reduction in catch rates in the

wider area of acoustic influence.

The impact of the proposed survey on the crab trap fishery is likely to be of regional extent and short-term duration. The impact is

expected to be of high intensity. The overall significance of the impact is assessed to be medium and the likelihood of the impact

occurring is probable. There fishery operates year-round but with relatively high fishing effort during June, July and August. The

period of closure to seismic surveying between June and November (as mitigation against potential impacts on cetaceans during

their annual migration period) would assist in reducing the impact on the fishery during this period; however the overall impact on

the fishery during the remainder of the year would remain of medium significance.

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The Angolan deep-sea red crab resource forms part of a single stock shared with Namibia, and it is targeted by the directed trap

fishery. The trap fishery operates within southern Angolan waters up to the Namibian maritime border and additional vessels

could be expected to be encountered in this area.

Figure 24: Spatial distribution of commercial catches (2003–2011) of deep-sea crab (Chaceon maritae) in Namibian waters and

in the vicinity of the proposed survey.

Impacts on the deep-sea crab fishing industry


Without

mitigation Regional High Short-term Probable MEDIUM – ve High





With


4.9 ROCK LOBSTER

The small but valuable fishery of rock lobster (Jasus lalandii) is based exclusively in the port of Lüderitz. Catch is landed whole

and is managed using a TAC. Historically, the fishery sustained relatively constant catches of up to 9000 tonnes per year until a

decline in the late 1960s. Figure 24 shows the commercial rock lobster TACs and actual catches from 1988 to 2012, with recent

TACs for 2014/15 and 2015/16 set at 300 tonnes 250 tonnes, respectively. The TACs have not been filled in the last 13 years and



this is thought to be caused by rough sea conditions that inhibit the feeding behaviour of rock lobster and subsequently lower their

catchability. The industry lands between 50% and 80% of the total TAC each season. The catch season is a six-month period

with a closed period extending from 1 May to 31 October and highest activity levels are experienced over January and February.

The number of active

vessels correlates to the allocated quota each season with 29

vessels active in 2010/11 and only 16 active during 2014/15

(E. Maletzky pers. com.). The number of active vessels

declines towards the end of the season.

The sector operates in water depths of between 10 and 80 m.

Baited traps consisting of rectangular metal frames covered

by netting, are deployed from small dinghy’s and delivered to

larger catcher reefers to take to shore for processing. The

rock lobster fishing fleet consists of vessels that range in

length from 7 m to 21 m. Traps are usually set in the late

morning and allowed to soak overnight before being retrieved

by winch early the following morning.

Within Namibian waters, the lobster stock is commercially exploited between 28º30'S and 25ºS from the Orange River border in

the south to Easter Cliffs/Sylvia Hill north of Mercury Island. The fishery is spatially managed through the demarcation of catch

grounds by management area, the closest of which is situated 820 km from the proposed survey area. As such there is no

impact expected on the rock lobster sector. The fishery does not operate within Angolan waters.

4.10 DEMERSAL LONG-LINE

Like the demersal trawl fishery the target species of this fishery is the Cape hakes, with a small non-targeted commercial by-catch

that includes kingklip8. The catch is landed as both prime quality (PQ) and headed and gutted hake. The catch is packed unfrozen

on ice. Long-line vessels fish in similar areas targeted by the hake-directed trawling fleet, in a broad area extending from the

300 m to 600 m contour along the full length of the Namibian coastline. Some 18 boats are currently (2016) operating within the

sector. Vessels based in Lüderitz mostly work South of 26°S towards the South Africa border while those based in Walvis Bay

operate between 23°S and 26°S and North of 23°S. Operations are ad hoc and intermittent, subject to market demand. A total

hake TAC of 140 000 t was set for 2015/16 but less than 10 000 t of this is caught by long-line vessels. Vessels operate year-

round but operations are particularly low in October and peak during December (see Figure 25).

Figure 25: Average monthly catch landed by the Namibian demersal long-line fleet (2000 – 2010).

8 Note: A new experimental demersal long-line fishery was recently established for kingklip in 2014/15. This fishery is expected to operate with three vessels

mostly on the “hard” grounds in the south Namibian waters towards the South African border. No spatial and catch effort data are yet available and it is

understood the experiment has ended.

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Figure 24: Catches and TAC of rock lobster in Namibia from

1988 to 2012 (source: State of Stocks Review, BCLME 2012).



A demersal long-line vessel may deploy either a double or single line which is weighted along it’s length to keep it close to the

seafloor (see Figure 26). Steel anchors, of 40 to 60 kg are placed at the ends of each line to anchor it. These anchor positions

are marked with an array of floats. If a double line system is used, top and bottom lines are connected by means of dropper lines.

Since the top-line (polyethylene, 10 – 16 mm diameter) is more buoyant than the bottom line, it is raised off the seafloor and

minimizes the risk of snagging or fouling. The purpose of the top-line is to aid in gear retrieval if the bottom line breaks at any

point along the length of the line. Lines are typically 20 – 30 nautical miles in length. Baited hooks are attached to the bottom line

at regular intervals (1 to 1.5 m) by means of a snood. Gear is usually set at night at a speed of 5 – 9 knots. Once deployed the

line is left to soak for up to eight hours before retrieval commences. A line hauler is used to retrieve gear (at a speed of

approximately 1 knot) and can take six to ten hours to complete. During hauling operations the vessel’s manoeuvrability is

severely restricted. Long-line vessels are similar in size and power to wet-fish trawlers and may vary in length from 18 m to 50 m

and remain at sea for four to seven days at a time.

Fishing grounds extend along the entire coastline following the distribution of hake along the continental shelf at a depth range of

approximately 200 m to 600 m (see Figure 27). Fishing activity would be expected throughout the survey area between these

depths. The proposed survey (which includes the maximum zone of disturbance) covers approximately 2 278 km2 or 1% of the

ground fished by the sector. Annual effort expended within the survey area between 2000 and 2010 amounts to approximately

18 000 hooks (0.01% of the total effort) and hake catch taken amounts to 1.2 tons (0.01% of the total longline catch). The

reduction in catch due to the influence of the acoustic signal beyond the survey area would be expected to result in a negligible

reduction in hake catch over the duration of the survey. It is important to note that fishing would be able continue in other areas,

and overall catch may not in fact be reduced. The impact of the proposed survey on the demersal long-line fishery is likely to be

of local extent and short-term duration. Based on the low level of fishing effort expended within the proposed survey area, the

intensity of the impact on the fishery is considered to be medium. The overall significance of the impact is assessed to be very

low and the likelihood of the impact occurring is probable. Angola does not target demersal finfish species using the long-lining

technique.

Figure 26: Typical configuration of demersal (bottom-set) gear used within

the demersal long-line fishery (Source: Japp, 1989).



Figure 27: Spatial distribution of catch reported by the demersal long-line fishery targeting Cape hakes (M. capensis; M.

paradoxus) between 2000 and 2010.

Impacts on the demersal longline fishing industry


Without

mitigation Local Medium Short-term Probable VERY LOW – ve High





With


4.11 LARGE PELAGIC LONG-LINE

This sector makes use of surface long-lines to target migratory pelagic species including yellowfin tuna (T. albacares), bigeye

tuna (T. obesus), swordfish (Xiphias gladius) and various pelagic shark species. Commercial landings of these species by the

fishery varies and can be as high as 6000 t per annum. There is provision for up to 26 fishing rights and 40 vessels (see rights

allocations on (http://www.mfmr.gov.na/). The actual number of long-line and tuna baitboat rights active in 2013/14 is however

uncertain and the assumption should be a maximum of 40 vessels.



Yellowfin tuna are distributed between 10ºS and 40ºS in the south Atlantic, and spawn in the central Atlantic off Brazil in the

austral summer (Penney et al. 1992). According to Crawford et al. (1987) juvenile and immature yellowfin tuna occur throughout

the year in the Benguela system. After reaching sexual maturity they migrate (in summer) from feeding grounds off the West

Coast of southern Africa to the spawning grounds in the central Atlantic. Bigeye tuna occurs in the Atlantic between 45ºN and

45ºS. Spawning takes place in the Gulf of Guinea and in the eastern central Atlantic north of 5ºN and it is thought that bigeye tuna

migrate to the Benguela system to feed. Swordfish spawn in warm tropical and subtropical waters and migrate to colder

temperate waters during summer and autumn months. Tuna are targeted at thermocline fronts, predominantly along and offshore

of the shelf break. Pelagic long-line vessels set a drifting mainline, up to 50-100 km in length, and are marked at intervals along

its length with radio buoys (Dahn) and floats to facilitate later retrieval. Various types of buoys are used in combinations to keep

the mainline near the surface and locate it should the line be cut or break for any reason. Between radio buoys the mainline is

kept near the surface or at a certain depth by means of ridged hard-plastic buoys, (connected via a “buoy-lines” of approximately

20 m to 30 m). The buoys are spaced approximately 500 m apart along the length of the mainline. Hooks are attached to the

mainline on branch lines, (droppers), which are clipped to the mainline at intervals of 20 m to 30 m between the ridged buoys.

The main line can consist of twisted tarred rope (6 mm to 8 mm diameter), nylon monofilament (5 mm to 7.5 mm diameter) or

braided monofilament (~6 mm in diameter). A line may be left drifting for up to 18 hours before retrieval by means of a powered

hauler at a speed of approximately 1 knot. Refer to Figure 28 for a photograph of a typical mainline and dropper line as well as a

schematic diagram of pelagic long-line gear.

Figure 28: Photograph of a mainline (braided monofilament) with a dropper line and trace (left) and schematic diagram of gear

typically used by the pelagic long-line fishery (right).

Long-line vessels targeting pelagic tuna species and swordfish operate extensively around the entire coast along the shelf-break

and into deeper waters. The spatial distribution of fishing effort is widespread and may be expected predominantly along the

shelf break (approximately along the 500 m isobath) and into deeper waters. Effort in this sector should be compared also with

the baitboat fishery as there are both spatial and temporal patterns associated with each fishery. Effort occurs year-round with

lower levels of fishing effort expected between June and October (see Figure 29).

Figure 29: Monthly average catch and effort recorded within the large pelagic long-line sector within Namibian waters (2008 –

2013).

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Figure 30: Spatial distribution of effort expended by the pelagic long-line fishery in relation to the proposed survey area. Effort is

displayed on a 60 x 60 minute grid as the cumulative number of hooks set between 2008 and 2013. Note that spatial distribution

of effort northwards of the Namibian border is incomplete as the Angolan commercial effort data were unavailable.

The spatial distribution of fishing effort is widespread and may be expected predominantly along the shelf break between the

500 m and 2000 m isobaths. Figure 30 shows the spatial distribution of fishing effort along the Namibian coastline and in the

vicinity of the proposed survey area, within which an average of 58 lines per year (130 000 hooks) were set. This is equivalent to

7.1% of the total annual effort expended by the fishery. Catch taken within the proposed survey area amounted to 145.7 tonnes

per year (6.4% of the total catch landed by the sector). The reduction in catch due to the influence of the acoustic signal beyond

the survey area would be expected to result in a reduction in catch of up to 0.01 tonnes per day. Thus the total loss over the 10

month survey is estimated to be in the order of 4 tonnes.

The impact of the proposed survey on the large pelagic long-line fishery is likely to be of regional extent and short-term duration.

The impact is expected to be of high intensity (fishing operations in the area are likely to be altered to the extent that they would

temporarily cease). The overall significance of the impact is assessed to be medium and the likelihood of the impact occurring is

highly probable. The confidence in the assessment is high.

Large pelagic species are caught seasonally in Angolan waters, and most of the fishing activity takes place in the southern fishing

grounds. It is highly likely that fishing vessels and set lines would be encountered across the maritime border into Angolan

waters.



Impacts on the large pelagic longline fishing industry


Without


Highly probable

MEDIUM – ve High





With


Highly probable

MEDIUM – ve High

4.12 TUNA POLE

Poling for tuna is predominantly based on the southern Atlantic albacore (longfin tuna) stock (T. alalunga) and a very small

amount of skipjack tuna (Katsuwonus pelamis), yellowfin tuna and bigeye tuna. The available records (provided by the

International Commission for the Conservation of Atlantic Tunas – ICCAT) are reported by Namibia for the whole EEZ and no

detailed spatial catch and effort data is therefore available. Catches of albacore tuna for Namibia and South Africa apply to what

is referred to as the Atlantic “southern stock” (ICCAT Statistical Bulletin 2012).

Historically catches of albacore tuna caught by South Africa and Namibia combined was very low, increasing steadily to a peak in

2000. Since 2000, catches have declined. This is consistent with the catch rate index used by ICCAT based on other fleets.

Nevertheless, ICCAT data show that fishing effort by the bait boat (tuna pole-and-line) in Namibia and South Africa has

persistently increased despite declines in catch rates. Note that as albacore move between the two areas and are caught by

many of the same boats from each country the reported fishing effort in Namibian and South African vessels should be used in

combination for interpretation (Figure 31 for Namibia). For Namibian vessels the peak fishing period for albacore is in the first

trimester tapering off from May.

Figure 31: Total nominal baitboat catch (t) seasonality of longfin tuna in Namibian waters for South African flagged vessels. Trimester 1 = January-March; T2 = April-June; T3 = July-September; T4 = October-December (ICCAT).

Figure 32: Schematic diagram of pole and line operation (Source: www.fao.org/fishery).

Concerns have recently been raised by the tuna fishing industry that seismic survey activities in southern Namibia are linked to

reductions in tuna catches. The scientific assessment undertaken by ICCAT in 2013 for the south Atlantic albacore (southern

stock) suggests that: “in 2012, the estimated South African and Namibian catch (mainly baitboat), was below the average of the

last five years”.

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The different models used suggested that:

• There is a wide confidence interval reflecting the large uncertainty around the estimates of stock status;

• Considering all scenarios, there is 57% probability for the stock to be both overfished and experiencing overfishing;

• There is a 13% probability for the stock to be either overfished or experiencing overfishing but not both, and;

• There is a 30% probability that biomass is above and fishing mortality is below the Convention objectives.

However, the scientific committee lacked enough objective information to identify the most plausible scenarios to account for the

variability and stock declines. The variability is most likely attributed to a combination of the following:

• Increasing fishing effort exacerbated by improved fish finding technology (vessel monitoring systems, use of sonar, sea

surface temperature spatial mapping using satellite technology;

• Environmental variability such as cold and warm water events e.g. Benguela “nino”;

• Migration and feeding patterns that change abundance levels annually and linked to the environment; and

• Inconsistent or irregular catch reporting.

Vessels operating within the fishery are typically small (< 25 m in length). Catch is stored on ice, chilled sea water or frozen and

the storage method often determines the range of the vessel. Trip durations average between four and five days, depending on

the distance of the fishing grounds from port.

Although the ICCAT data available do not support detailed spatial analysis, it is known that aggregations of albacore tuna occur in

specific areas – in particular Tripp Seamount just north of the South Africa-Namibia border. Catches in this area are however

variable from year to year, although boats will frequent the area knowing that albacore aggregate around Tripp Seamount after

migrating through South African waters. Movements of albacore between South Africa and Namibia is not clear although it is

believed the fish move northwards following bathymetric features and generally stay deeper than 200 m water depth9.

Approximately 36 South African pole and line vessels operate under arrangements with Namibian right holders each year, and

landed catch the period 2011 was approximately 4000 t. The fishery is seasonal with vessel activity mostly from January to April

and peak catches in February, March and April (Figure 33). Effort fluctuates according to the availability of fish in the area, but

once a shoal of tuna is located a number of vessels will move into the area and target a single shoal which may remain in the

area for days at a time. As such the fishery is dependent on window periods of favourable conditions relating to catch availability.

Within Namibian waters, the fishery operates primarily southwards of 25°S between the 200 m and 500 m isobaths and in

particular over Tripp Seamount (see Figure 34). Due to the distance of the proposed survey from the closest area fished by the

tuna pole sector (approximately 320 km), there is no impact expected on the fishery in Namibia and Angola.

Figure 33: Average monthly catch and effort recorded by the tuna pole and line fleet in Namibian waters (2008 – 2013).

9 Please note the ICCAT data used in this assessment is based on data up to 2011 and on the ICCAT stock assessments conducted in 2012.

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Figure 34: Spatial distribution of fishing effort expended by the tuna pole and line fleet along the Namibian coastline and in the

vicinity of the proposed seismic survey design.

4.13 LINE-FISH

The traditional line fishery is based on only a few species that includes silver kob (Argyrosomus inodorus), dusky kob (A.

coronus), snoek (Thyrsites atun) and shark which are sold on the local market or exported. The fishery is limited in extent mostly

northwards of Walvis Bay and does not operate much further than 12 nm offshore. The two commercial components of the line-

fish fishery comprise a fleet of between 10 and 13 ski-boats and a fleet of 26 industrial vessels (included under the Tuna Pole

sector – see section 4.12). Whilst ski-boats fish close to the shore in the vicinity of Swakopmund and Walvis Bay, the industrial

vessels fish offshore areas. Commercial operators sell line-fish on the local market as well as exporting, largely to South Africa.

The distribution of linefish catch in relation to the proposed survey area is shown in Figure 35. Due to the distance of the

proposed survey from the areas fished by the commercial linefish sector, there is no impact expected on the fishery in Namibia

and Angola.



Figure 35: Spatial range of ski-boats operating within the line-fish sector along the Namibian coastline.

4.14 FISHERIES RESEARCH

MFMR conducts regular research (biomass) surveys for demersal, mid-water and small pelagic species. In some years the

Benguela Current Commission may conduct “transboundary” surveys. Swept-area biomass surveys for hake are conducted

annually to obtain an index of abundance, determine the geographical distribution and collect biological information of the stock.

From 1990 to 1999, these surveys were conducted with the Norwegian R/V Dr Fridtjof Nansen (Sætersdal et al 1999). Since

2000, Namibian commercial trawlers (using the same trawl gears as that of the Dr Fridtjof Nansen) were used for the surveys.

Since 2002, the commercial trawler F/V Blue Sea 1 has been used to conduct these surveys. These surveys are normally carried

out over the period of one month during January and February and cover the entire continental shelf from the Angolan to the

South African maritime border. The method of abundance estimation from these surveys is based on depth stratification and

trawls range in depth from 100 m to 600 m. During trawling the vessel tows the net for a period of 30 minutes at a speed of

approximately 3 knots.

Scientific acoustic surveys are carried out between February and March each year to estimate the biomass of small pelagic

species (using the survey vessel F/V Welwitchia). These surveys cover the Namibian shelf from the coastline to the 500 m depth

contour (and up to the 2000 m contour northwards of 18°30´S). The vessel surveys along pre-determined transects that run

perpendicular to depth contours (East-West / West-East direction).

Figure 36 shows the location of all demersal trawl stations in relation to the proposed survey area. An average of 216 trawls are

carried out per survey, of which an average of 11 trawls (5.1%) are undertaken within the proposed survey area. As the timing of

the research surveys and survey plan is structured, the window period during which trawls in this area took place ranged between

the 12th and 20th of February (based on surveys carried out between 2007 and 2012). The depth of trawls undertaken within the

proposed survey area ranged between 135 m and 600 m. Acoustic research survey activity could be expected within the

proposed seismic survey area to a maximum depth of 2000 m. Approximately 18 of a total of 66 survey transects undertaken in

2014 coincide with the proposed survey area – this is equivalent to 27.3% of the total number of transects surveyed during a

single cruise.



Figure 36: Stations layout of the entire Namibian region covered during hake swept-area biomass surveys conducted between

the 100 m and 600 m depth contours.

The proposed seismic survey would coincide with the research survey transects and trawl stations undertaken during biomass

surveys during this period. The impact on fisheries research cruises is likely to be of local to regional extent and short-term

duration. The impact is expected to be of medium to high intensity and the overall significance of the impact is assessed to be

very low to medium without mitigation and very low to low with mitigation. Mitigation measures would include liaison with

research vessels to co-ordinate acoustic surveys and trawling operations as necessary during the months of February and March.

Impacts on fisheries research

Demersal trawl surveys


Without





• At sea communications to maintain adequate safety clearance between research vessels and the survey operation.

• Co-ordination of seismic survey to allow research trawls to take place as needed.

With

mitigation Local

Low to

Medium Short-term Probable VERY LOW – ve High



Impacts on fisheries research

Small pelagic acoustic surveys


Without





• At sea communications to maintain adequate safety clearance between research vessels and the survey operation.

• Co-ordination of seismic survey to allow the passage of research vessel along designated transects as needed.

With

mitigation Regional Medium Short-term Probable LOW – ve High

5. SUMMARY AND RECOMMENDATIONS

The proposed 3D survey would take in the order of 9-10 months to complete, covering an area of 12 940 km2 in the Namibe

Basin, offshore northern Namibia. During survey operations, the vessel would travel at a speed of between 4 and 5 knots along a

series of transects, pre-selected to cross a suspected area of geological interest. As the vessel would be towing an array of

hydrophone cables and would therefore have severely restricted manoeuvrability, all other vessels would be required to remain at

a distance of up to 16 km from the vessel. (The exact safety clearance requests would be decided by the captain of the vessel.)

The proposed survey could potentially affect fisheries that operate within the area through temporary exclusion from fishing

grounds. The table below shows the operational periods of only those fishing sectors whose fishing grounds overlap the proposed

survey area.

Whale mitigation (closed to survey)

J F M A M J J A S O N D

Small pelagic purse-seine x x x x x x x x x x x x

Mid-water trawl X X X X X X X X X X X X

Demersal trawl X X X X X X X X X n/f x x

Deep-water trawl Fishery currently closed

Deep-sea crab x x x x x X X X x x x x

Demersal long-line x x x x x x x x x x x x

Large pelagic long-line X X X X X x x x x x x X

Fisheries research X X n/f n/f n/f n/f n/f n/f n/f n/f n/f n/f

Key

n/f No fishing effort

x Low fishing effort

X Moderate to high fishing effort

Lowest impact period

Medium impact period

Highest impact period

It is likely that several Namibian fishing sectors would be affected by the proposed survey namely the small pelagic purse-seine

(improbable), mid-water trawl (highly probable), demersal trawl (highly probable), deep-sea crab (probable), demersal long-line

(probable) and large pelagic long-line sectors (highly probable). The significance of the impact of the proposed survey on each of

the sectors ranges from very low (small pelagic purse-seine and demersal long-line), to low (demersal trawl) to medium (mid-

water trawl, large pelagic long-line and deep-sea crab). The impact on the demersal trawl fishery could be reduced by timing the

survey to coincide with a period of no fishing during the month of October, and periods of relatively low fishing effort during



November and December. To a large extent this would be achieved by the period of closure to seismic surveying between June

and November (as mitigation against potential impacts on cetaceans during their annual migration period). There is no impact

expected on the deep-water trawl, rock lobster, tuna pole and linefish sectors. Biomass estimation of demersal species (trawl

surveys) and small pelagic species (acoustic surveys) are undertaken within the proposed seismic survey area each year. These

surveys are carried out during fixed periods (January and February for demersal trawls and late February to March for acoustic

surveys of small pelagic species). The impact of the proposed seismic survey on fisheries research surveys is assessed to be of

overall medium (acoustic) to very low (demersal) significance without mitigation, and of low (acoustic) to very low (demersal)

significance with mitigation. The significance of the impact could be minimised by allowing research survey activities to be

undertaken as necessary and this could be achieved through at-sea communications between the seismic and research survey

vessels.

The following general mitigation measures are proposed in order to minimise disruptions to both the survey and fishing

operations:

1. Prior to the commencement of the survey, the fishing industry, MFMR and other interested and affected parties should

be informed of the pending activity and the likely implications for the various fishing sectors in the area as well as

research surveys planned to coincide with the proposed seismic operations.;

2. Radio Navigational Warnings should be issued for the duration of the surveying operations through the South African

Naval Hydrographic Office (SANHO) and daily notifications should be issued by Walvis Bay Radio;

3. An experienced Fisheries Liaison Officer (FLO) should be deployed on board the survey vessel to facilitate

communication with maritime vessels (The FLO should report daily on vessel activity and respond and advise on action

to be taken in the event of encountering fishing gear);

4. A daily electronic reporting routine should be set up to keep interested and affected parties informed of survey activity,

fisheries interactions and environmental issues;

5. Due to the likely interaction with fishers and fishing gear it is strongly recommended that the survey vessel be

accompanied by a chase vessel with staff familiar with the fishers expected in the area.

6. The impact on each fishery has been assessed based on the spatial overlap of fishing grounds by the cumulative

survey area and therefore assumes the scenario that fishing activity would be excluded from the entire area. In reality,

the exclusion zone covers only a portion of the cumulative survey area as the vessel progresses systematically from

one part of the project area to another over the course of 10 months. It is therefore unlikely that fishing vessels would

be excluded from operating within the entire survey area for the full duration of the project. It is possible that time-

sharing of the project area could be achieved with pro-active and on-going communications between the survey and

fishing vessels. This time-sharing would be strongly encouraged as a means of reducing the impact on fisheries that

operate within the survey area, in particular the midwater trawl fishery.

Communications with the fishing industry should be established through the Association of Namibian Fishing Industries (covers

most sectors as a collective secretariat). In addition, the Namibian Hake Association, Namibian Monk and Sole Association,

Midwater Trawling Association of Namibia, Namibian Tuna and Hake Longlining Association and Pelagic Fishing Association

should be notified. The operator of crab trap vessels should be contacted directly and informed of the intended survey period.

With respect to annual research cruises undertaken by MFMR and the BCC, it is advised that there be consultation with these

organisations prior to the commencement of the project to coordinate and minimise possible disruption of both activities.

The following sector-specific liaison is recommended:

• Demersal and Mid-water Trawl: Identify vessels – due to proximity to trawl grounds, notification of survey areas of

operation is essential. With good communication and reduced time in the area disruption of fishing activity can be

minimised.

• Demersal Long-line: Identify gear (marked at each end by a surface buoy) - hake long-liners generally stay close to

their lines when gear is deployed and communication with skippers on the position of set gear is essential.

• Pelagic Long-line: Establish communications with the known operators prior to commencement of the survey and if

drifting buoys (with radar responders) are sighted.



6. REFERENCES

Benguela Current Large Marine Ecosystem State of Stocks Review 2011 (2nd Edition; Ed C. Kirchner). Benguela Current

Commission.

Botha L (1980) The biology of the Cape hakes Merluccius capensis Cast. and M. paradoxus Franca in the Cape of Good Hope

area Ph.D. thesis, University of Stellenbosch (182 pp.)

Boyer D C and Hampton I (2001) An overview of the living marine resources of Namibia in A decade of Namibian Fisheries

Science S. Afr. J. mar. Sci (23) Eds Payne A I L, Pillar S C and Crawford R J M.

Branch, T.A. 2001. A review of orange roughy Hoplostethus atlanticus fisheries, estimation methods, biology and stock structure.

S. Afr. J. mar. Sci. 23: 181 – 203

Cochrane, K.L. and S. Wilkinson. 2015. Assessment of the potential impacts on the small pelagic fishery of the proposed 2D

seismic survey by Rhino Oil and Gas Exploration South Africa (Pty) Ltd in the inshore area between Saldanha Bay and Cape

Agulhas. Prepared for SLR Environmental Consultants (Pty) Ltd; unpublished.

Crawford R J M, Shannon L V and Pollock D E (1987) The Benguela ecosystem (4) The major fish and invertebrate resources In

Oceanography and Marine Biology: An Annual Review 25 Barnes M (Ed) Aberdeen; University Press (353-505).

Dalen, J., Dragsund, E., Næss, A. & Sand, O. 2007. Effects of seismic surveys on fish, fish catches and sea mammals.

Cooperation group – Fishery industry and Petroleum industry, Rep. No. 2007-0512, 33p, Stavanger, Norway.

Fisheries and Aquaculture industry in Namibia. The Ministerial Conference on Fisheries Cooperation among African States

Bordering the Atlantic Ocean (ATFALCO): Series Report No. 2 on the Fisheries and Aquaculture review in the 22 ATLAFCO

member countries. October 2012.

Holness, S., Wolf, T., Lombard M. and C. Kirchner. 2012. Spatial Biodiversity Assessment and Spatial Management, including

Marine Protected Areas: Spatial summary of pressures on marine systems. Benguela Current Commission.

Japp, D.W. 1989. An Assessment of the South African Longline Fishery with Emphasis on Stock Integrity of Kingklip. Genypterus

capensis (Pisces: Ophidiidae). MSc thesis, Rhodes University (138 pp.).

King D P F (1977) Influence of temperature, dissolved oxygen and salinity on incubation and early larval development of the

South West African pilchard Sardinops ocellata Invenstl Rep. Sea Fish. Brch S. Afr. 114 (35 pp.)

Kirchner, C., Bauleth-d’Almeida, G. and M. Wilhelm. 2010. Assessment and management of Cape horse mackerel Trachurus

trachurus capensis off Namibia based on a fleet-disaggregated age-structured production model. African Journal of Marine

Science, 32(3).

Fishing Industry Handbook South Africa, Namibia and Moçambique (2016) 44th edition George Warman Publications

Le Roux L (1997) Stock assessment and population dynamics of the deep-sea red crab Chaceon maritae (Brachyura,

Geryonidae) off the Namibian Coast M.Sc. thesis, Univerisity of Iceland (88 pp.)

Leslie R W and Grant W S (1990) Lack of congruence between genetic and morphometric stock structure of the southern African

anglerfish Lophius vomerinus S. Afr. J. mar. Sci. 9 (379-398)

Macpherson E (1985) Daily ration and feeding periodicity of some fishes off the coast of Namibia Mar. Ecol. Prog. Ser. 26(3):

253-260

Olivar M P, Rubies P and Salat J (1988) Early life history and spawning of Merluccius capensis Castelnau in the northern

Benguela Current S. Afr. J. mar. Sci. 6 (245-254)



O’Toole M J (1977) Investigation into some important fish larvae in the South-East Atlantic Ph.D. thesis University of Cape Town

(299 pp.)

Pulfrich, A. 2015. Environmental Impact Assessment for LK Mining’s Proposed Marine Exploration Activities in EPL 5965: Marine

Ecology Specialist Study. Prepared for SLR Environmental Consulting (Namibia) (Pty) Ltd.

Russell, D. 2013. Key Issues and Possible Impacts of Seismic Activities on Tunas: For the Large Pelagic and Hake Longlining

Association in Namibia. Presented at Benguela Current Commission 5th Annual Science Forum. 24 September 2013.

Schneider, GIC. 2013. Seismic Acquisitions and the Impact on the Large Pelagic Albacore Tuna Pole and Line Industry in

Namibia. Geological survey of Namibia

Staby and J-O. Krakstad. Report on BCLME project LMR/CF/03/08:Review of the state of knowledge, research (past and

present) of the distribution, biology, ecology, and abundance of non-exploited mesopelagic fish (Order Anguilliformes,

Argentiniformes, Stomiiformes, Myctophiformes, Aulopiformes) and the bearded goby (Sufflogobius bibarbatus) in the Benguela

Ecosystem.

Sætersdal G, Bianchi G, Strømme T, Venema SC (1999) The Dr Fridtjof Nansen programme 1975–1993. Investigation of fishery

resources in developing countries. History of the programme and review of results. FAO fisheries technical paper 391, Rome

Strømme .T, Lipinski M.R. and P. Kainge (2015) Life cycle of hake and likely management implications. Rev Fish Biol Fisheries

Wilhelm, M and A. Kanandjembo 2007. Biomass and biological data from the Namibian annual horse mackerel abundance

surveys, updated for 2007. MFMR



APPENDIX 1: CONVENTION FOR ASSIGNING SIGNIFICANCE RATINGS TO IMPACTS

1. EXTENT

“Extent” defines the physical extent or spatial scale of the impact.

Rating Description

LOCAL Extending only as far as the activity, limited to the site and its immediate surroundings.

Specialist studies to specify extent. Impacted area covers less than 10% of the total ground

available to a particular fishing sector.

REGIONAL Limited to the Northern Namibian Coast. Impacted area covers more than 10% of the total

ground available to a particular fishing sector.

NATIONAL Limited to the coastline of Namibia. Impacted area covers the entire extent of fishing ground

available to a particular fishing sector.

INTERNATIONAL Extending beyond the borders of Namibia.

2. DURATION

“Duration” gives an indication of how long the impact would occur.

Rating Description

SHORT TERM 0 - 5 years

MEDIUM TERM 6 - 15 years

LONG TERM Where the impact would cease after the operational life of the activity, either because of natural

process or human intervention.

PERMANENT Where mitigation either by natural processes or by human intervention would not occur in such

a way or in such time span that the impact can be considered transient.

3. INTENSITY

“Intensity” establishes whether the impact would be destructive or benign.

Rating Description

ZERO TO VERY

LOW

Where the impact affects the environment in such a way that natural, cultural and social

functions and processes are not affected.

LOW Where the impact affects the environment in such a way that natural, cultural and social

functions and processes continue, albeit in a slightly modified way.

MEDIUM Where the affected environment is altered, but natural, cultural and social functions and

processes continue, albeit in a modified way.

HIGH Where natural, cultural and social functions or processes are altered to the extent that it will

temporarily or permanently cease.



4. SIGNIFICANCE

“Significance” attempts to evaluate the importance of a particular impact, and in doing so incorporates the

above three scales (i.e. extent, duration and intensity).

Rating Description


of high intensity at a regional level and endure in the long term10

;




of high intensity at a regional level and endure in the medium term;















of low intensity at a regional level and endure in the medium term;





OR of medium intensity at a local level and endure in the medium term.




OR of low to medium intensity at a local level and endure in the short term.


Zero to very low intensity with any combination of extent and duration.

UNKNOWN In certain cases it may not be possible to determine the significance of an impact.

5. STATUS OF IMPACT

The status of an impact is used to describe whether the impact would have a negative, positive or zero

effect on the affected environment. An impact may therefore be negative, positive (or referred to as a

benefit) or neutral.

10

For any impact that is considered to be “Permanent” apply the “Long-Term” rating.



6. PROBABILITY

“Probability” describes the likelihood of the impact occurring.

Rating Description

IMPROBABLE Where the possibility of the impact to materialise is very low either because of design or

historic experience.

PROBABLE Where there is a distinct possibility that the impact would occur.

HIGHLY PROBABLE Where it is most likely that the impact would occur.

DEFINITE Where the impact would occur regardless of any prevention measures.

7. DEGREE OF CONFIDENCE

This indicates the degree of confidence in the impact predictions, based on the availability of information

and specialist knowledge.

Rating Description

HIGH Greater than 70% sure of impact prediction.

MEDIUM Between 35% and 70% sure of impact prediction.

LOW Less than 35% sure of impact prediction.

APPENDIX 3

MARINE FAUNAL ASSESSMENT

ENVIRONMENTAL IMPACT ASSESSMENT FOR A PROPOSED 3D SEISMIC SURVEY

OFF THE COAST OF NORTHERN NAMIBIA

Marine Faunal Assessment

Prepared for:

On behalf of:


June 2017

April 2012

ENVIRONMENTAL IMPACT ASSESSMENT FOR A PROPOSED

3D SEISMIC SURVEY, OFF THE COAST OF NORTHERN NAMIBIA

MARINE FAUNAL ASSESSMENT

Prepared for


On behalf of:


Prepared by

Andrea Pulfrich Pisces Environmental Services (Pty) Ltd

With contributions by:

Simon Elwen and Tess Gridley

Namibian Dolphin Project Mammal Research Institute (University of Pretoria)

June 2017

Contact Details:

Andrea Pulfrich

Pisces Environmental Services

PO Box 31228, Tokai 7966, South Africa,

Tel: +27 21 782 9553, Fax: +27 21 782 9552


Website: www.pisces.co.za

IMPACTS ON MARINE FAUNA –3D Seismic Survey, Northern Namibia

Pisces Environmental Services (Pty) Ltd i

TABLE OF CONTENTS

1. GENERAL INTRODUCTION .................................................................................... 1

1.1. Scope of Work ...................................................................................... 1

1.2. Approach to the Study ............................................................................ 2

2. DESCRIPTION OF THE PROPOSED PROJECT ............................................................... 3

3. DESCRIPTION OF THE BASELINE MARINE ENVIRONMENT ................................................ 5

3.1. Geophysical Characteristics...................................................................... 5

3.1.1 Bathymetry ................................................................................. 5

3.1.2 Coastal and Inner-shelf Geology and Seabed Geomorphology ..................... 5

3.2. Biophysical Characteristics ....................................................................... 6

3.2.1 Climate ...................................................................................... 6

3.2.2 Wind Patterns .............................................................................. 8

3.2.3 Large-Scale Circulation and Coastal Currents ...................................... 10

3.2.4 Waves and Tides ......................................................................... 13

3.2.5 Water ...................................................................................... 13

3.2.6 Upwelling & Plankton Production ..................................................... 15

3.2.7 Turbidity .................................................................................. 15

3.2.8 Organic Inputs ............................................................................ 16

3.2.9 Low Oxygen Events ...................................................................... 16

3.2.10 Sulphur Eruptions ...................................................................... 17

3.3. The Biological Environment .................................................................... 18

3.3.1 Demersal Communities ................................................................. 19

3.3.2 Seamount Communities................................................................. 22

3.3.3 Pelagic Communities .................................................................... 24

3.4. Other Uses of the proposed Survey Areas ................................................... 44

3.4.1 Beneficial Uses ........................................................................... 44

3.4.2 Conservation Areas and Marine Protected Areas ................................... 45

4. ACOUSTIC IMPACTS OF SEISMIC SURVEYS ON MARINE FAUNA ........................................ 47

4.1. Impacts on Plankton ............................................................................. 48

4.2. Impacts on Marine Invertebrates .............................................................. 49

4.3. Impacts on Fish ................................................................................... 50

4.4. Impacts on Seabirds ............................................................................. 52

4.5. Impacts on Turtles ............................................................................... 52

4.6. Impacts on Seals ................................................................................. 55


Pisces Environmental Services (Pty) Ltd ii

4.7. Impacts on Whales and Dolphins .............................................................. 56

4.7.1 Cetacean vocalisations ................................................................. 57

4.7.2 Cetacean hearing ........................................................................ 57

4.7.3 Physiological injury and stress ........................................................ 58

4.7.4 Behavioural disturbance ................................................................ 60

4.7.5 Masking of important environmental or biological sounds ....................... 62

4.7.5 Indirect effects on prey species ...................................................... 62

5. ASSESSMENT OF ACOUSTIC IMPACTS ON MARINE FAUNA ............................................. 63

5.1. Assessment Procedure .......................................................................... 63

5.2. Assessment of Impacts .......................................................................... 65

5.2.1 Impacts to Plankton ..................................................................... 65

5.2.2 Impacts to Marine Invertebrates ...................................................... 66

5.2.3 Impacts to Fish ........................................................................... 68

5.2.4 Impacts to Seabirds ..................................................................... 72

5.2.5 Impacts to Turtles ....................................................................... 75

5.2.6 Impacts to Seals.......................................................................... 77

5.2.7 Impacts to Whales and Dolphins ...................................................... 80

6. CONCLUSIONS AND RECOMMENDATIONS ................................................................ 87

6.1. Conclusions ....................................................................................... 87

6.2. Recommended Mitigation Measures .......................................................... 87

7. LITERATURE CITED .......................................................................................... 93


Pisces Environmental Services (Pty) Ltd iii

ABBREVIATIONS and UNITS

cm centimetres

cm/s centimetres per second

CMS Centre for Marine Studies

CSIR Council for Scientific and Industrial Research

dB decibells

EIA Environmental Impact Assessment

EMP Environmental Management Programme

EPLs Exclusive Prospecting Licences

FAO Food and Agricultural Organisation

GSN Geological Survey of Namibia

g C/m2/day grams Carbon per square metre per day

g/m2 grams per square metre

h hour

H2S hydrogen sulphide

HABs harmful algal blooms

Hz Herz

IUCN International Union for the Conservation of Nature

IWC International Whaling Commission

IR infrared

JNCC Joint Nature Conservation Committee

kHz kiloHerz

km kilometre

km/h kilometres per hour

km2 square kilometre

kts knots

LUCORC Lüderitz upwelling cell - Orange River Cone

MCM Marine and Coastal Management

MET Ministry of Environment and Tourism


MMO Marine Mammal Observer

MPA Marine Protected Area

m metres

mg/l milligrams per litre

mm millimetres

m/sec metres per second

N north

NDP Namibian Dolphin Project

NW north-west

OMZs Oxygen Minimum Zones

PAM Passive Acoustic Monitoring

PIM Particulate Inorganic Matter

POM Particulate Organic Matter

PTS permanent threshold shifts

ROVs Remote Operated Vehicles


Pisces Environmental Services (Pty) Ltd iv

S south

SACW South Atlantic Central Water

SEL Sound Exposure Level

SLR SLR Environmental Consulting (Namibia) (Pty) Ltd

SPL sound pressure level

SW south-west


TSPM Total Suspended Particulate Matter

TTS temporary threshold shifts

UPC Universal Power Corp

VOS Voluntary Observing Ships

VMEs Vulnerable Marine Ecosystems

WSW west south-west

2D two-dimensional

3D three-dimensional

µg/l micrograms per litre

µPa micro Pascal

°C degrees Centigrade

% percent

‰ parts per thousand

~ approximately

< less than

> greater than


Pisces Environmental Services (Pty) Ltd v


This report was prepared by Dr Andrea Pulfrich of Pisces Environmental Services (Pty) Ltd. Andrea has a PhD in Fisheries Biology from the Institute for Marine Science at the Christian-Albrechts University, Kiel, Germany.

As Director of Pisces since 1998, Andrea has considerable experience in undertaking specialist environmental impact assessments, baseline and monitoring studies, and Environmental Management Programmes relating to marine diamond mining and dredging, hydrocarbon exploration and thermal/hypersaline effluents. She is a registered Environmental Assessment Practitioner and member of the South African Council for Natural Scientific Professions, South African Institute of Ecologists and Environmental Scientists, and International Association of Impact Assessment (South Africa).

This specialist report was compiled for SLR Environmental Consulting (Namibia) (Pty) Ltd on behalf of Spectrum Geo Limited for their use in preparing an Environmental Impact Assessment for a proposed 3D seismic survey off the coast of Northern Namibia. I do hereby declare that Pisces Environmental Services (Pty) Ltd is financially and otherwise independent of the Applicants and SLR.

Dr Andrea Pulfrich


Pisces Environmental Services (Pty) Ltd vi


The section of this report relating to marine mammal presence and seaonality in the

proposed study area was prepared by Dr Simon Elwen of the Namibian Dolphin Project and the University of Pretoria (Mammal Research Institute) in consultation with Dr Andrea Pulfrich.

Simon Elwen has MSc and PhD degrees from the University of Pretoria with both degree theses focusing on cetacean biology in South Africa. He has more than 10 years experience studying cetacean ecology off the west coast of Africa.

This specialist report was compiled as a desktop study on behalf of Pisces Environmental Services (Pty) Ltd and SLR Environmental Consulting (Namibia) (Pty) Ltd.

The compilation followed a review process of published (peer reviewed) and unpublished literature.

I do hereby declare that I am financially and otherwise independent of the Applicant, Pisces Environmental Services and SLR Environmental Consulting (Namibia) (Pty) Ltd.

Simon Elwen, PhD


Pisces Environmental Services (Pty) Ltd 1

1. GENERAL INTRODUCTION

Hydrocarbon deposits occur in reservoirs in sedimentary rock layers. Being lighter than water they accumulate in traps where the sedimentary layers are arched or tilted by folding or faulting of the geological layers. Marine seismic surveys are the primary tool for locating such deposits and are thus an indispensable component of offshore oil or gas exploration.

Seismic survey programmes comprise data acquisition in either two-dimensional (2D) and/or three dimensional (3D) scales, depending on information requirements. 2D surveys are typically applied to obtain regional data from widely spaced survey grids and provide a vertical slice through the seafloor geology along the survey track-line. Infill surveys on closer grids subsequently provide more detail over specific areas of interest. In contrast, 3D seismic surveys are conducted on a very tight survey grid, and provide a cube image of the seafloor geology along each survey track–line. Such surveys are typically applied to promising petroleum prospects to assist in fault line interpretation.

The nature of the sound impulses utilised during seismic surveys have resulted in concern over their potential impact on marine fauna, particularly marine mammals, fish, and turtles (McCauley et al. 2000). Consequently, it has been proposed that environmental management already be applied at the exploration stage of the a life cycle of a hydrocarbon field project (Duff et al. 1997, in Salter & Ford 2001).

For this investigation Spectrum Geo Limited (Spectrum) is proposing to undertake a speculative 3D seismic survey, offshore of the coast of northern Namibia. The purpose of this survey would be to investigate the subsea geology for the presence of oil and gas prospects. SLR Environmental Consulting (Namibia) (Pty) Ltd (SLR) has been appointed to undertake an Environmental Impact Assessment (EIA) for the proposed seismic survey. SLR in turn has approached Pisces Environmental Services (Pty) Ltd to provide a specialist assessment on potential impacts of the proposed operations on marine fauna in the area.

1.1. Scope of Work

This specialist report was compiled as a desktop study on behalf of SLR, for their use in compiling an EIA report for the proposed 3D seismic survey off the northern Namibian coast.

The terms of reference for this study, as specified by SLR, are:

• Provide a general description of the local marine fauna in and around the proposed seismic area;

• Identify, describe and assess the significance of potential impacts of the proposed seismic survey on the local marine fauna, focussing particularly on marine mammals and turtles, but including generic effects on fish and pelagic and benthic invertebrates; and

• Identify practicable mitigation measures to reduce any negative impacts and indicate how these could be implemented in the implementation and management of the proposed project.



1.2. Approach to the Study

As determined by the terms of reference, this study has adopted a ‘desktop’ approach. Consequently, the description of the natural baseline environment in the study area is based on a review and collation of existing information and data from the scientific literature, internal reports and the Generic Environmental Management Programme Report (EMPR) compiled for oil and gas exploration in South Africa (CCA & CMS 2001). The information for the identification of potential impacts was drawn from various scientific publications, the Generic EMPR, information sourced from the Internet as well as Marine Mammal Observer Close-out Reports. The sources consulted are listed in the Reference chapter.

All identified marine impacts are summarised, categorised and ranked in appropriate impact assessment tables, to be incorporated in the overall EIA Report.



2. DESCRIPTION OF THE PROPOSED PROJECT

Spectrum is proposing to undertake a speculative 3D seismic survey covering an area of ~12,940 km2 in the Namibe Basin, offshore of northern Namibian (Figure 1). The proposed survey area is located beyond the 150 m depth contour to approximately 4,000 m depth, with the closest point to shore being approximately 25 km.

Although survey commencement would ultimately depend on a licence award date, Spectrum proposes to commence with the 3D seismic survey in the fourth quarter of 2017. It is anticipated that the proposed 3D seismic would take in the order of nine (9) to ten (10) months to complete.

Figure 1: Map indicating location of proposed 3D survey area (shaded) offshore of northern

Namibia. Depth contours and places mentioned in the text are also indicated.

A 3D survey typically involves towed airgun arrays, which provide the seismic source

energy for the profiling process, and seismic wave detector systems, usually known as hydrophone streamers. The sound source or airgun arrays would be situated some 80 m to 150 m behind the vessel at a depth of 5 m to 25 m below the surface. A 3D survey typically involves multiple streamers (up to 12 streamers spaced 100 m apart) up to 12,000 m long, towed at a depth of between 6 m and 30 m and would not be visible, except for the tail-buoy at the far end of the cable.



The survey vessel would steam a series of predefined transects describing the survey grid, the headings of which would be fixed and reciprocal. Consequently the survey vessel would be restricted in manoeuvrability (a turn radius of 4.5 km is expected), and other vessels should remain clear of it. A supply/chase vessel usually assists in the operation of keeping other vessels at a safe distance.

Each triggering of a sound pulse is termed a seismic shot, and these are fired at intervals of 10-15 seconds (Barger & Hamblen 1980). Each seismic shot is usually only between 5 and 30 milliseconds in duration, and despite peak levels within each shot being high, the total energy delivered into the water is low.

Airguns have most of their energy in the 0-120 Hz frequency range, with the optimal frequency required for deep penetration seismic work being 50-80 Hz. The maximum sound pressure levels at the source of air-gun array would be in the range 220-230 dB re 1µPa at 1 m (McCauley 1994; NRC 2003).

Seismic shots are of short duration (the main pulse is usually between 5 and 30 milliseconds in duration), with the main pulse being followed by a negative pressure reflection from the sea surface of several lower magnitude bubble pulses. Despite peak levels within each shot being high, the total energy delivered into the water is low.



3. DESCRIPTION OF THE BASELINE MARINE ENVIRONMENT

The descriptions of the physical and biological environments along the northern Namibian coast cover the offshore area from the Kunene River in the north to Walvis Bay in the south. The purpose of this environmental description is to provide the marine baseline environmental context within which the proposed seismic survey will take place. The summaries presented below are based on information gleaned from Lane & Carter (1999), Morant (2006), and Penney et al. (2007).

3.1. Geophysical Characteristics

3.1.1 Bathymetry

The continental shelf off Namibia is variable in width. Off the Orange River the shelf is wide (230 km) and characterised by well-defined shelf breaks, a shallow outer shelf and the aerofoil-shaped submarine Recent River Delta on the inner shelf. It narrows to the north reaching its narrowest point (90 km) off Chameis Bay, before widening again to 130 km off Lüderitz (Rogers 1977). Off Terrace Bay the shelf gives rise to the Walvis Ridge, an underwater plateau extending south-westwards far into the south Atlantic, before narrowing again towards Cape Frio (see Figure 1). Off Walvis Bay there is a double shelf break, with the inner and outer breaks beginning at depths of around 140 m and 400 m, respectively (Shannon & O’Toole 1998).

The salient topographic features of the shelf include the relatively steep descent to about 100 m, the gentle decline to about 180 m, and the undulating depths to about 200 m. The most prominent topographic feature in the study area is the Walvis Ridge, which extends from the African coast at around 18°S more than 3,000 km southwestwards to Tristan da Cunha, the Gough Islands and the Mid-Atlantic Ridge. This plateau effectively splits the abyssal plain of the Southeast Atlantic into the Angola Basin to the north and the Cape Basin to the south. The variable topography of the shelf is of significance for nearshore circulation and for fisheries (Shannon & O’Toole 1998).

3.1.2 Coastal and Inner-shelf Geology and Seabed Geomorphology

Figure 2 illustrates the distribution of seabed surface sediment types off the northern Namibian coast. The inner shelf is underlain by Precambrian bedrock (also referred to as Pre-Mesozoic basement), whilst the middle and outer shelf areas are composed of Cretaceous and Tertiary sediments (Dingle 1973; Birch et al. 1976; Rogers 1977; Rogers & Bremner 1991). As a result of erosion on the continental shelf, the unconsolidated sediment cover is generally thin, often less than 1 m. Sediments are finer seawards, changing from sand on the inner and outer shelves to muddy sand and sandy mud in deeper water. However, this general pattern has been modified considerably by biological deposition (large areas of shelf sediments contain high levels of calcium carbonate) and localised river input. Off central Namibia, the muddy sand in the nearshore area off Henties Bay gives way to a tongue of organic-rich sandy mud, which extends from south of Sandwich Harbour to ~ 20°40’S (Figure 2). These biogenic muds are the main determinants of the formation of low-oxygen waters and sulphur eruptions off central Namibia (see Sections 3.2.9 & 3.2.10). Further offshore these give way to muddy sands, sands and gravels before changing again into mud-dominated seabed beyond the 500-m



contour. The continental slope, seaward of the shelf break, has a smooth seafloor, underlain by calcareous ooze.

Figure 2: The project area in relation to the sediment distribution on the continental shelf off

northern Namibia (Adapted from Rogers 1977).

3.2. Biophysical Characteristics

3.2.1 Climate

The climate of the Namibian coastline is classified as hyper-arid with typically low, unpredictable winter rains and strong predominantly southerly or south-westerly winds. Further out to sea, a south-easterly component is more prominent. Winds reach a peak in the late afternoon and subside between midnight and sunrise.

The Namibian coastline is characterised by the frequent occurrence of fog, which occurs on average between 50-75 days per year, being most frequent during the months of February through May (Figure 3). The fog lies close to the coast extending about 20 nautical miles (~35 km) seawards (Olivier, 1992, 1995). This fog is usually quite dense, appears as a thick bank hugging the shore and visibility may be reduced to <300 m.



Figure 3: Fog day frequency for 1984 using Meteosat Images (Adapted from Olivier 1992, 1995).



Average precipitation per annum along the coastal region between Walvis Bay and the Kunene River is <15 mm. Due to the combination of wind and cool ocean water, temperatures are mild throughout the year. Coastal temperatures average around 16°C, gradually increasing inland (Barnard 1998). In winter, maximum diurnal shifts in temperature can occur caused by the hot easterly ‘Berg’ winds which blow off the desert. During such occasions temperatures up to 30°C are not uncommon.

3.2.2 Wind Patterns

Winds are one of the main physical drivers of the nearshore Benguela region, both on an oceanic scale, generating the heavy and consistent south-westerly swells that impact this coast, and locally, contributing to the northward-flowing longshore currents, and being the prime mover of sediments in the terrestrial environment. Consequently, physical processes are characterised by the average seasonal wind patterns, and substantial episodic changes in these wind patterns have strong effects on the entire Benguela region.

The prevailing winds in the Benguela region are controlled by the South Atlantic subtropical anticyclone, the eastward moving mid-latitude cyclones south of southern Africa, and the seasonal atmospheric pressure field over the subcontinent. The south Atlantic anticyclone is a perennial feature that forms part of a discontinuous belt of high-pressure systems that encircle the subtropical southern hemisphere. This undergoes seasonal variations, being strongest in the austral summer, when it also attains its southernmost extension, lying south west and south of the subcontinent. In winter, the south Atlantic anticyclone weakens and migrates north-westwards.

These seasonal changes result in substantial differences between the typical summer and winter wind patterns in the region, as the southern hemisphere anti-cyclonic high-pressure system, and the associated series of cold fronts, move northwards in winter, and southwards in summer. The strongest winds occur in summer, when winds blow 99% of the time. Virtually all winds in summer are strongly dominated by southerlies, which occur over 40% of the time, averaging 20 - 30 kts and reaching speeds in excess of 60 kts. In northern Namibia long-shore southeasterly winds dominate in summer, whereas off Walvis Bay south-southwesterlies dominate and wind speeds are generally lower on average and display less seasonality than in the south of the country (Shannon & O’Toole 1998). These southerly winds bring cool, moist air into the coastal region and drive the massive offshore movements of surface water, and the resultant strong upwelling of nutrient-rich bottom waters, which characterise this region in summer. The winds also play an important role in the loss of sediment from beaches. These strong equatorwards winds are interrupted by the passing of coastal lows with which are associated periods of calm or north or northwest wind conditions. These northerlies occur throughout the year, but are more frequent in spring and summer.

Winter remains dominated by southerly winds, but the closer proximity of the winter cold-front systems results in a significant south-westerly to north-westerly component. This ‘reversal’ from the summer condition results in cessation of upwelling, movement of warmer mid-Atlantic water shorewards and breakdown of the strong thermoclines which typically develop in summer. Seasonal wind roses for Pelican Point near Walvis Bay, are illustrated in Figures 4 (supplied by PRDW 2008).

During autumn and winter, catabatic, or easterly ‘berg’ winds can also occur. These powerful offshore winds can exceed 50 km/h, producing sandstorms that considerably reduce visibility at sea and on land. Although they occur intermittently for about a week at a time,



they have a strong effect on the coastal temperatures, which often exceed 30°C during ‘berg’ wind periods (Shannon & O’Toole 1998). The winds also play a significant role in sediment input into the coastal marine environment with transport of the sediments up to 150 km offshore (Figure 5).

Figure 4: Seasonal wind roses for Pelican Point (Source PRDW 2008).



Figure 5: Satellite image showing aerosol plumes of sand and dust being blown out to sea during a

northeast 'berg' wind event along the central Namibian coast (Image source:

www.intute.ac.uk).

3.2.3 Large-Scale Circulation and Coastal Currents

The Namibian coastline is strongly influenced by the Benguela Current. Current velocities in continental shelf areas generally range between 10–30 cm/s (Boyd & Oberholster 1994). In the south the Benguela current has a width of 200 km, widening rapidly northwards to 750 km. The flows are predominantly wind-forced, barotropic and fluctuate between poleward and equatorward flow (Shillington et al. 1990; Nelson & Hutchings 1983) (Figure 6). Fluctuation periods of these flows are 3 - 10 days, although the long-term mean current residual is in an approximate northwest (alongshore) direction. Near bottom shelf flow is mainly poleward (Nelson 1989) with low velocities of typically 5 cm/s.

The Angola Dome lies to the north of the survey area and is characterised by cyclonic circulation, with periodic intrusion of tropical waters into the northern Benguela from the north and northwest. Off the coast of Angola, the most prominent circulation feature is the southward flowing Angola current, which turns westwards between 16°S and 17°S just north of the Angola-Benguela Front. The Angola-Benguela Front is a permanent feature at the surface and to a depth of at least 200 m between latitudes 14°S and 17°S. The front is maintained by a combination of factors including coastal orientation, wind stress, bathymetry and opposing flows of the Angola and Benguela Currents. To what extent the Angola Current contributes to the Benguela system at the surface and subsurface off northern Namibia is uncertain. At greater depths (400 m), however, the poleward flow of the Angola Current is more continuous. The episodic southward movement of this front during late summer introduces warm tropical water southwards and eastwards along the Namibian coast. Known as Beguela Niños, these events occur on average every ten years (Shannon & O’Toole 1998).



Figure 6: The project area (red polygon) in relation to major features of the predominant

circulation patterns and volume flows in the Benguela System (re-drawn from Shannon &

Nelson 1996).

The major feature of the Benguela Current is coastal upwelling and the consequent high nutrient supply to surface waters leads to high biological production and large fish stocks. The prevailing longshore, equatorward winds move nearshore surface water northwards and offshore. To balance the displaced water, cold, deeper water wells up inshore. Although the rate and intensity of upwelling fluctuates with seasonal variations in wind patterns, the most intense upwelling tends to occur where the shelf is narrowest and the wind strongest. Consequently, it is a semi-permanent feature at Lüderitz and areas to the north due to



perennial southerly winds (Shannon 1985). The Lüderitz upwelling cell is the most intense upwelling cell in the system (Figure 7), with the seaward extent reaching nearly 300 km, and the upwelling water is derived from 300-400 m depth (Longhurst 2006). A detailed analysis of water mass characteristics revealed a discontinuity in the central and intermediate water layers along the shelf north and south of Lüderitz (Duncombe Rae 2005). The Lüderitz / Orange River region thus forms a major environmental barrier between the northern and southern Benguela sub-systems (Ekau & Verheye 2005). Off central and northern Namibia, several secondary upwelling cells occur. Upwelling in these cells is perennial, with a late winter maximum (Shannon 1985).

Figure 7: The project area in relation to the upwelling centres and low oxygen areas on the west

coast of Namibia (Adapted from Shannon 1985).



3.2.4 Waves and Tides

The Namibian Coast is classified as exposed, experiencing strong wave action rating between 13-17 on the 20-point exposure scale (McLachlan 1980). The coastline is influenced by major swells generated in the roaring forties, as well as significant sea waves generated locally by the persistent southerly winds.

Typical seasonal swell-height rose-plots, compiled from Voluntary Observing Ship (VOS) data off Walvis Bay are shown in Figure 8 (supplied by CSIR). The wave regime along the southern African west coast shows only moderate seasonal variation in direction, with virtually all swells throughout the year coming from the SW - S direction. In winter there is a slight increases in swell from SW direction. The median significant wave height is 2.4 m with a dominant peak energy period of ~12 seconds. Longer period swells (11 to 15 seconds), generated by mid-latitude cyclones occur about 25-30 times a year. These originate from the S-SW sectors, with the largest waves recorded along the southern African West Coast attaining 4-7 m. With wind speeds capable of reaching 100 km/h during heavy winter south-westerly storms, winter swell heights can exceed 10 m. Generally, wave heights decrease with water depth and distance longshore.

In comparison, spring and summer swells tend to be smaller on average, typically around 2 m, not reaching the maximum swell heights of winter. There is also a more pronounced southerly swell component in summer. These southerly swells tend to be wind-induced, with shorter wave periods (~8 seconds), and are generally steeper than swell waves (CSIR 1996). These wind-induced southerly waves are relatively local and, although less powerful, tend to work together with the strong southerly winds of summer to cause the northward-flowing nearshore surface currents, and result in substantial nearshore sediment mobilisation, and northwards transport, by the combined action of currents, wind and waves.

In common with the rest of the southern African coast, tides are semi-diurnal, with a total range of some 1.5 m at spring tide, but only 0.6 m during neap tide periods.

3.2.5 Water

South Atlantic Central Water (SACW) comprises the bulk of the seawater in the study area, either in its pure form in the deeper regions, or mixed with previously upwelled water of the same origin on the continental shelf (Nelson & Hutchings 1983). Salinities range between 34.5‰ and 35.5‰ (Shannon 1985).

Data recorded over a ten year period at Swakopmund (1988 – 1998) showed that seawater temperatures vary between 10°C and 23°C, averaging 14.9°C. Well-developed thermal fronts exist, demarcating the seaward boundary of the upwelled water. Upwelling filaments are characteristic of these offshore thermal fronts, occurring as surface streamers of cold water, typically 50 km wide and extending beyond the normal offshore extent of the upwelling cell. Such fronts typically have a lifespan of a few days to a few weeks, with the filamentous mixing area extending up to 625 km offshore.

The continental shelf waters of the Benguela system are characterised by low oxygen concentrations, especially on the bottom. SACW itself has depressed oxygen concentrations (~80% saturation value), but lower oxygen concentrations (<40% saturation) frequently occur (Bailey et al. 1985; Chapman & Shannon 1985).



Figure 8: Seasonal offshore wave conditions for a data point located at 23° S, 13.75°E (Source:

CSIR 2009).

Nutrient concentrations of upwelled water of the Benguela system attain 20 µm nitrate-nitrogen, 1.5 µm phosphate and 15-20 µm silicate, indicating nutrient enrichment (Chapman & Shannon 1985). This is mediated by nutrient regeneration from biogenic material in the sediments (Bailey et al. 1985). Modification of these peak concentrations depends upon phytoplankton uptake which varies according to phytoplankton biomass and production rate. The range of nutrient concentrations can thus be large but, in general, concentrations are high.



3.2.6 Upwelling & Plankton Production

The cold, upwelled water is rich in inorganic nutrients, the major contributors being various forms of nitrates, phosphates and silicates (Chapman & Shannon 1985). During upwelling the comparatively nutrient-poor surface waters are displaced by enriched deep water, supporting substantial seasonal primary phytoplankton production. This, in turn, serves as the basis for a rich food chain up through zooplankton, pelagic baitfish (anchovy, pilchard, round-herring and others), to predatory fish (hake and snoek), mammals (primarily seals and dolphins) and seabirds (jackass penguins, cormorants, pelicans, terns and others). High phytoplankton productivity in the upper layers again depletes the nutrients in these surface waters. This results in a wind-related cycle of plankton production, mortality, sinking of plankton detritus and eventual nutrient re-enrichment occurring below the thermocline as the phytoplankton decays.

3.2.7 Turbidity

Turbidity is a measure of the degree to which the water loses its transparency due to the presence of suspended particulate matter. Total Suspended Particulate Matter (TSPM) can be divided into Particulate Organic Matter (POM) and Particulate Inorganic Matter (PIM), the ratios between them varying considerably. The POM usually consists of detritus, bacteria, phytoplankton and zooplankton, and serves as a source of food for filter-feeders. Seasonal microphyte production associated with upwelling events will play an important role in determining the concentrations of POM in coastal waters. PIM, on the other hand, is primarily of geological origin consisting of fine sands, silts and clays. Off the southern African West Coast, the PIM loading in nearshore waters is strongly related to natural riverine inputs. ‘Berg’ wind events can potentially contribute the same order of magnitude of sediment input as the annual estimated input of sediment by the Orange River (Shannon & Anderson 1982; Zoutendyk 1992, 1995; Shannon & O’Toole 1998; Lane & Carter 1999).

Concentrations of suspended particulate matter in shallow coastal waters can vary both spatially and temporally, typically ranging from a few mg/l to several tens of mg/l (Bricelj & Malouf 1984; Berg & Newell 1986; Fegley et al. 1992). Field measurements of TSPM and PIM concentrations in the Benguela current system have indicated that outside of major flood events, background concentrations of coastal and continental shelf suspended sediments are generally <12 mg/l, showing significant long-shore variation (Zoutendyk 1995). Considerably higher concentrations of PIM have, however, been reported from southern African West Coast waters under stronger wave conditions associated with high tides and storms, or under flood conditions.

The major source of turbidity in the swell-influenced nearshore areas off the West Coast is the redistribution of fine inner shelf sediments by long-period Southern Ocean swells. The current velocities typical of the Benguela (10-30 cm/s) are capable of resuspending and transporting considerable quantities of sediment equatorwards. Under relatively calm wind conditions, however, much of the suspended fraction (silt and clay) that remains in suspension for longer periods becomes entrained in the slow poleward undercurrent (Shillington et al. 1990; Rogers & Bremner 1991).

Superimposed on the suspended fine fraction, is the northward littoral drift of coarser bedload sediments, parallel to the coastline. This northward, nearshore transport is generated by the predominantly south-westerly swell and wind-induced waves. Longshore sediment



transport varies considerably in the shore-perpendicular dimension, being substantially higher in the surf-zone than at depth, due to high turbulence and convective flows associated with breaking waves, which suspend and mobilise sediment (Smith & Mocke 2002).

On the inner and middle continental shelf, the ambient currents are insufficient to transport coarse sediments, and resuspension and shoreward movement of these by wave-induced currents occur primarily under storm conditions (see also Drake et al. 1985; Ward 1985).

3.2.8 Organic Inputs

The Benguela upwelling region is an area of particularly high natural productivity, with extremely high seasonal production of phytoplankton and zooplankton. These plankton blooms in turn serve as the basis for a rich food chain up through pelagic baitfish (anchovy, pilchard, round-herring and others), to predatory fish (snoek), mammals (primarily seals and dolphins) and seabirds (jackass penguins, cormorants, pelicans, terns and others). All of these species are subject to natural mortality, and a proportion of the annual production of all these trophic levels, particularly the plankton communities, die naturally and sink to the seabed.

Balanced multispecies ecosystem models have estimated that during the 1990s the Benguela region supported biomasses of 76.9 tons/km2 of phytoplankton and 31.5 tons/km2 of zooplankton alone (Shannon et al. 2003). Thirty six percent of the phytoplankton and 5% of the zooplankton are estimated to be lost to the seabed annually. This natural annual input of millions of tons of organic material onto the seabed off the southern African West Coast has a substantial effect on the ecosystems of the Benguela region. It provides most of the food requirements of the particulate and filter-feeding benthic communities that inhabit the sandy-muds of this area, and results in the high organic content of the muds in the region. As most of the organic detritus is not directly consumed, it enters the seabed decomposition cycle, resulting in subsequent depletion of oxygen in deeper waters.

An associated phenomenon ubiquitous to the Benguela system are red tides (dinoflagellate and/or ciliate blooms) (see Shannon & Pillar 1985; Pitcher 1998). Also referred to as Harmful Algal Blooms (HABs), these red tides can reach very large proportions. Toxic dinoflagellate species can cause extensive mortalities of fish and shellfish through direct poisoning, while degradation of organic-rich material derived from both toxic and non-toxic blooms results in oxygen depletion of subsurface water.

3.2.9 Low Oxygen Events

The continental shelf waters of the Benguela system are characterised by low oxygen concentrations with <40% saturation occurring frequently (e.g. Visser 1969; Bailey et al. 1985). The low oxygen concentrations are attributed to nutrient remineralisation in the bottom waters of the system (Chapman & Shannon 1985). The absolute rate of this is dependent upon the net organic material build-up in the sediments, with the carbon rich mud deposits playing an important role. As the mud on the shelf is distributed in discrete patches (see Figure 2), there are corresponding preferential areas for the formation of oxygen-poor water (Figure 7). The two main areas of low-oxygen water formation in the central Benguela region are in the Orange River Bight and off Walvis Bay (Chapman & Shannon 1985; Bailey 1991; Shannon & O’Toole 1998; Bailey 1999; Fossing et al. 2000). The spatial distribution of oxygen-poor water in each



of the areas is subject to short- and medium-term variability in the volume of hypoxic water that develops. De Decker (1970) showed that off Lambert’s Bay in South Africa, the occurrence of low oxygen water is seasonal, with highest development in summer/autumn. Bailey & Chapman (1991), on the other hand, demonstrated that in the St Helena Bay area in South Africa, daily variability exists as a result of downward flux of oxygen through thermoclines and short-term variations in upwelling intensity. Subsequent upwelling processes can move this low-oxygen water up onto the inner shelf, and into nearshore waters, often with devastating effects on marine communities.

Periodic low oxygen events in the nearshore region can have catastrophic effects on the marine communities leading to large-scale stranding of rock lobsters, and mass mortalities of marine biota and fish (Newman & Pollock 1974; Matthews & Pitcher 1996; Pitcher 1998; Cockcroft et al. 2000). The development of anoxic conditions as a result of the decomposition of huge amounts of organic matter generated by algal blooms is the main cause for these mortalities and walkouts. The blooms develop over a period of unusually calm wind conditions when sea surface temperatures where high. Algal blooms usually occur during summer-autumn (February to April) but can also develop in winter during the ‘berg’ wind periods, when similar warm windless conditions occur for extended periods.

3.2.10 Sulphur Eruptions

Closely associated with seafloor hypoxia, particularly off central Namibia, is the generation of toxic hydrogen sulphide and methane within the organically-rich, anoxic muds following decay of expansive algal blooms. Under conditions of severe oxygen depletion, hydrogen sulphide (H2S) gas is formed by anaerobic bacteria in anoxic seabed muds (Brüchert et al. 2003). This is periodically released from the muds as ‘sulphur eruptions’, causing upwelling of anoxic water and formation of surface slicks of sulphur discoloured water (Emeis et al. 2004), and even the temporary formation of floating mud islands (Waldron 1901). Such eruptions are accompanied by a characteristic pungent smell along the coast and the sea takes on a lime green colour (Figure 9). These eruptions strip dissolved oxygen from the surrounding water column, resulting in mass mortalities of marine life. Such complex chemical and biological processes are often associated with the occurrence of harmful algal blooms, causing large-scale mortalities to fish and crustaceans (see above).

Sulphur eruptions have been known to occur off the Namibian coast for centuries (Waldron 1901), and the biota in the area are likely to be naturally adapted to such pulsed events, and to subsequent hypoxia. However, satellite remote sensing has recently shown that eruptions occur more frequently, are more extensive and of longer duration than previously suspected, and that resultant hypoxic conditions last longer than thought (Weeks et al. 2002, 2004).

Recently the role of micro-organisms in the detoxification of sulphidic water was investigated during the occurrence of a sulphidic water mass covering 7,000 km2 of seafloor off the coast of Namibia (http://www.mpi-bremen.de/Projekte_9.html; http://idw-online.de/ pages/de/ news292832), when surface waters, however, remained well oxygenated. In the presence of oxygen, sulphide is oxidized and transformed into non-toxic forms of sulphur. An intermediate layer was discovered in the water column, which contained neither hydrogen sulphide nor oxygen. It was established that sulphide diffusing upwards from the anoxic bottom water is consumed by autotrophic denitrifying bacteria that inhabit the intermediate water layer. By using nitrate, the detoxifying microorganisms transform sulphide into finely



dispersed particles of sulphur that are non-toxic, thereby creating a buffer zone between the toxic deep water and the oxygenated surface waters. These results, however, also suggest that benthic and demersal animals in coastal waters may be affected by sulphur eruptions more often than previously thought, and that many of these sulphidic events may go unnoticed on satellite imagery as the bacteria consume the hydrogen sulphide before it reaches the surface. Figure 9: Satellite image showing discoloured water offshore the Namib Desert resulting from a

nearshore sulphur eruption (satellite image source: www.intute.ac.uk). Inset shows a

photograph taken from shore at Sylvia Hill, north of Lüderitz, during such an event in

March 2002 (photograph by J. Kemper, MFMR, Lüderitz).

3.3. The Biological Environment

Biogeographically, the study area falls into the warm-temperate Namib Province, which extends northwards from Lüderitz into southern Angola (Emanuel et al. 1992). The portion of the proposed survey area that extends beyond the shelf break onto the continental slope and into abyssal depths falls into the Atlantic Offshore Bioregion (Lombard et al. 2004). The coastal, wind-induced upwelling characterising the Namibian coastline, is the principle physical process that shapes the marine ecology of the Benguela region. The Benguela system is characterised by the presence of cold surface water, high biological productivity, and highly variable physical, chemical and biological conditions. During periods of less intence winds off the northern Nambian coast (Benguela Niños), upwelling weakens and the warmer, more saline waters of the Angola Current intrude southwards along the coast introducing organisms normally associated with the subtropical conditions typical off Angola (Barnard 1998). As these events are typically temporary, the species of tropical west African origin associated with them will not be discussed here.

Communities within marine habitats are largely ubiquitous throughout the southern African West Coast region, being particular only to substrate type or depth zone. These biological communities consist of many hundreds of species, often displaying considerable temporal and spatial variability (even at small scales). The majority of the proposed survey



area is located beyond the 150 m depth contour, the closest points to shore for the 3D survey being ~25 km off the coast west off Cape Frio. The near- and offshore marine ecosystems comprise a limited range of habitats, namely unconsolidated seabed sediments and the water column. The biological communities ‘typical’ of these habitats are described briefly below, focussing both on dominant, commercially important and conspicuous species, as well as potentially threatened or sensitive species, which may be affected by the proposed seismic survey.

3.3.1 Demersal Communities

3.3.1.1 Benthic Invertebrate Macrofauna

The benthic biota of unconsolidated marine sediments constitute invertebrates that live on (epifauna) or burrow within (infauna) the sediments, and are generally divided into macrofauna (animals >1 mm) and meiofauna (<1 mm). Numerous studies have been conducted on southern African West Coast continental shelf benthos, mostly focused on mining, pollution or demersal trawling impacts (Christie & Moldan 1977; Moldan 1978; Jackson & McGibbon 1991; Environmental Evaluation Unit 1996; Parkins & Field 1997; 1998; Pulfrich & Penney 1999; Goosen et al. 2000; Savage et al. 2001; Steffani & Pulfrich 2004a, 2004b; 2007; Steffani 2007a; 2007b; Steffani 2009, 2010; Steffani 2012). The description below is drawn from the various baseline and monitoring surveys conducted by diamond mining companies (Bickerton & Carter 1995; Steffani & Pulfrich 2007; Steffani 2007a; 2007b).

Polychaetes, crustaceans and molluscs make up the largest proportion of individuals, biomass and species on the west coast. The distribution of species within these communities are inherently patchy reflecting the high natural spatial and temporal variability associated with macro-infauna of unconsolidated sediments (e.g. Kenny et al. 1998; Kendall & Widdicombe 1999; van Dalfsen et al. 2000; Zajac et al. 2000; Parry et al. 2003), with evidence of mass mortalities and substantial recruitments recorded on the South African West Coast (Steffani & Pulfrich 2004a). Generally species richness increases from the inner shelf across the mid shelf and is influenced by sediment type (Karenyi unpublished data). The highest total abundance and species diversity was measured in sandy sediments of the mid-shelf. Biomass is highest in the inshore (± 50 g/m2 wet weight) and decreases across the mid-shelf averaging around 30 g/m2 wet weight. The midshelf mudbelt, however, is a particularly rich benthic habitat where biomass can attain 60 g/m2 dry weight (Christie 1974; see also Steffani 2007b). The comparatively high benthic biomass in this mudbelt region represents an important food source to carnivores such as the mantis shrimp, cephalopods and demersal fish species (Lane & Carter 1999). In deeper water beyond this rich zone biomass declines to 4.9 g/m2 at 200 m depth and then is consistently low (<3 g/m2) on the outer shelf (Christie 1974).

The benthic fauna of the outer shelf and continental slope (beyond ~450 m depth) are very poorly known largely due to limited opportunities for sampling as well as the lack of access to Remote Operated Vehicles (ROVs) for visual sampling of hard substrata. To date very few areas of the continental slope off the southern African West Coast have been biologically surveyed.

Whilst many empirical studies related community structure to sediment composition (e.g. Christie 1974; Warwick et al. 1991; Yates et al. 1993; Desprez 2000; van Dalfsen et al. 2000), other studies have illustrated the high natural variability of soft-bottom communities, both in space and time, on scales of hundreds of metres to metres (e.g. Kenny et al. 1998; Kendall &



Widdicombe 1999; van Dalfsen et al. 2000; Zajac et al. 2000; Parry et al. 2003), with evidence of mass mortalities and substantial recruitments (Steffani & Pulfrich 2004a). It is likely that the distribution of marine communities in the mixed deposits of the coastal zone is controlled by complex interactions between physical and biological factors at the sediment–water interface, rather than by the granulometric properties of the sediments alone (Snelgrove & Butman 1994; Seiderer & Newell 1999). For example, off central Namibia it is likely that periodic intrusion of low oxygen water masses is a major cause of this variability (Monteiro & van der Plas 2006; Pulfrich et al. 2006). Although there is a poor understanding of the responses of local continental shelf macrofauna to low oxygen conditions, it is safe to assume that in areas of frequent oxygen deficiency the communities will be characterised by species able to survive chronic low oxygen conditions, or colonising and fast-growing species able to rapidly recruit into areas that have suffered complete oxygen depletion. Local hydrodynamic conditions, and patchy settlement of larvae, will also contribute to small-scale variability of benthic community structure.

It is evident that an array of environmental factors and their complex interplay is ultimately responsible for the structure of benthic communities. Yet the relative importance of each of these factors is difficult to determine as these factors interact and combine to define a distinct habitat in which the animals occur. However, it is clear that water depth and sediment composition are two of the major components of the physical environment determining the macrofauna community structure off the west coast of southern Africa (Steffani & Pulfrich 2004a, 2004b, 2007; Steffani 2007a, 2007b, 2009a, 2009b, 2009c, 2010). However, in the deepwater shelf areas off central Namibia, it is likely that occurrence of Oxygen Minimum Zones (OMZs) and the periodic intrusion of low oxygen water masses will play a major role in determining variability in community structure (Monteiro & van der Plas 2006).

Specialised benthic assemblages (protozoans and metazoans) can thrive in OMZs (Levin 2003), and many organisms have adapted to low oxygen conditions by developing highly efficient ways to extract oxygen from depleted water. Within OMZs, benthic foraminiferans, meiofauna and macrofauna typically exhibit high dominance and relatively low species richness. In the OMZ core, where oxygen concentration is lowest, macrofauna and megafauna (>10 cm) often have depressed densities and low diversity, despite being able to form dense aggregations at OMZ edges (Levin 2003, Levin et al. 2009). Taxa most tolerant of severe oxygen depletion (~0.2 ml/ℓ) include calcareous foraminiferans, nematodes, and polychaetes, with agglutinated protozoans, harpacticoid copepods, and calcified invertebrates typically being less tolerant. Small-bodied animals, with greater surface area for O2 adsorption, are thought to be more prevalent than large-bodied taxa under conditions of permanent hypoxia as they are better able to cover their metabolic demands and often able to metabolise anaerobically (Levin 2003). Meiofauna may thus increase in dominance in relation to macro- and megafauna. This was not the case, however, within the lower OMZs of the Oman (Levin et al. 2000) and Pakistan margins (Levin et al. 2009), where the abundant food supply in the lower or edge OMZs is thought to be responsible for promoting larger macrofaunal body size.

There is a poor understanding of the responses of local continental shelf macrofauna to low oxygen conditions, as very little is known about the benthic fauna specific to the Namibian OMZ. It is safe to assume that in areas of frequent oxygen deficiency the communities will be characterised by species able to survive chronic low oxygen conditions, or colonising and fast-growing species able to rapidly recruit into areas that have suffered complete oxygen



depletion. Local hydrodynamic conditions, and patchy settlement of larvae, will also contribute to small-scale variability of benthic community structure.

Recent data collected from between 150 m and 300 m depth offshore of the area between Meob Bay and Conception Bay showed that overall species richness of benthic macrofauna assemblages was relatively low and strongly dominated by polychaetes, particularly the spionid polychaete Paraprionospio pinnata. This species is dominant in oxygen-constrained environments worldwide. Crustaceans were poorly represented, both in terms of abundance and biomass (Steffani 2011). The phyla distribution is generally in common with other OMZs around the world.

It is evident that an array of environmental factors and their complex interplay is ultimately responsible for the structure of benthic communities. Yet the relative importance of each of these factors is difficult to determine as these factors interact and combine to define a distinct habitat in which the animals occur.

Also associated with soft-bottom substrates are demersal communities that comprise epifauna and bottom-dwelling invertebrate and vertebrate species, many of which are dependent on the invertebrate benthic macrofauna as a food source. An invertebrate demersal species of commercial importance in Namibia is the deepsea red crab Chaceon maritae, which occurs at depths of 300-1,000 m along the entire west coast of Africa from West Sahara to central Namibia. In Namibia, densities are highest between the Kunene and latitude 18°S. Larger animals tend to occur more frequently between latitudes 20° - 23°S, where densities are lower. The species is slow-growing taking up to 25-30 years to reach maximum size. Females occur at depths of 350-500 m, whereas males become more dominant in deeper water (Le Roux 1998). Spawning occurs throughout the year. 3.3.1.2 Deep-water coral communities

There has been increasing interest in deep-water corals in recent years because of their likely sensitivity to disturbance and their long generation times. These benthic filter-feeders generally occur at depths exceeding 150 m. Some species form reefs while others are smaller and remain solitary. Corals add structural complexity to otherwise uniform seabed habitats thereby creating areas of high biological diversity (Breeze et al. 1997; MacIssac et al. 2001). Deep water corals establish themselves below the thermocline where there is a continuous and regular supply of concentrated particulate organic matter, caused by the flow of a relatively strong current over special topographical formations which cause eddies to form. Nutrient seepage from the substratum might also promote a location for settlement (Hovland et al. 2002). Substantial shelf areas in the productive Benguela region should thus potentially be capable of supporting rich, cold water, benthic, filter-feeding communities. Such communities would also be expected with topographic features such as the Walvis Ridge (and its associated seamounts) to the south of the project area.

3.3.1.3 Demersal Fish Species

As many as 110 species of bony and cartilaginous fish have been identified in the demersal communities on the continental shelf of the southern African West Coast (Roel 1987). Changes in fish communities occur with increasing depth (Roel 1987; Smale et al. 1993; Macpherson & Gordoa 1992; Bianchi et al. 2001; Atkinson 2009), with the most substantial change in species composition occurring in the shelf break region between 300 m and 400 m



depth (Roel 1987; Atkinson 2009). Common commercial demersal species found mostly on the continental shelf but also extending beyond 500 m water depth include both the shallow-water hake, Merluccuis capensis and the deep-water hake (Merluccius paradoxus), monkfish (Lophius vomerinus), and kingklip (Genypterus capensis). There are also many other demersal “bycatch” species that include jacopever (Helicolenus dactylopterus), angelfish/pomfret (Brama brama), kingklip (Genypterus capensis) and gurnard (Chelidonichtyes sp), as well as several cephalopod species (such as squid and cuttlefishes) and many elasmobranch (sharks and rays) species (Compagno et al. 1991).

Roel (1987) showed seasonal variations in the distribution ranges shelf communities, with species such as the pelagic goby Sufflogobius bibarbatus, and West Coast sole Austroglossus microlepis occurring in shallow water during summer only. The deep-sea community was found to be homogenous both spatially and temporally. In a more recent study, however, Atkinson (2009) identified two long-term community shifts in demersal fish communities; the first (early to mid-1990s) being associated with an overall increase in density of many species, whilst many species decreased in density during the second shift (mid-2000s). These community shifts correspond temporally with regime shifts detected in environmental forcing variables (Sea Surface Temperatures and upwelling anomalies) (Howard et al. 2007) and with the eastward shifts observed in small pelagic fish species and rock lobster populations (Coetzee et al. 2008, Cockcroft et al. 2000).

3.3.2 Seamount Communities

Features such as banks, knolls and seamounts (referred to collectively here as “seamounts”), which protrude into the water column, are subject to, and interact with, the water currents surrounding them. The effects of such seabed features on the surrounding water masses can include the up-welling of relatively cool, nutrient-rich water into nutrient-poor surface water thereby resulting in higher productivity (Clark et al. 1999), which can in turn strongly influences the distribution of organisms on and around seamounts. Evidence of enrichment of bottom-associated communities and high abundances of demersal fishes has been regularly reported over such seabed features.

The enhanced fluxes of detritus and plankton that develop in response to the complex current regimes lead to the development of detritivore-based food-webs, which in turn lead to the presence of seamount scavengers and predators. Seamounts provide an important habitat for commercial deepwater fish stocks such as orange roughy, oreos, alfonsino and Patagonian toothfish, which aggregate around these features for either spawning or feeding (Koslow 1996).

Such complex benthic ecosystems in turn enhance foraging opportunities for many other predators, serving as mid-ocean focal points for a variety of pelagic species with large ranges (turtles, tunas and billfish, pelagic sharks, cetaceans and pelagic seabirds) that may migrate large distances in search of food or may only congregate on seamounts at certain times (Hui 1985; Haney et al. 1995). Seamounts thus serve as feeding grounds, spawning and nursery grounds and possibly navigational markers for a large number of species (SPRFMA 2007).

Enhanced currents, steep slopes and volcanic rocky substrata, in combination with locally generated detritus, favour the development of suspension feeders in the benthic communities characterising seamounts (Rogers 1994). Deep- and cold-water corals (including stony corals, black corals and soft corals) are a prominent component of the suspension-feeding fauna of many seamounts, accompanied by barnacles, bryozoans, polychaetes, molluscs, sponges, sea



squirts, basket stars, brittle stars and crinoids (reviewed in Rogers 2004). There is also associated mobile benthic fauna that includes echinoderms (sea urchins and sea cucumbers) and crustaceans (crabs and lobsters) (reviewed by Rogers 1994). Some of the smaller cnidarians species remain solitary while others form reefs thereby adding structural complexity to otherwise uniform seabed habitats. The coral frameworks offer refugia for a great variety of invertebrates and fish (including commercially important species) within, or in association with, the living and dead coral framework thereby creating spatially fragmented areas of high biological diversity. Compared to the surrounding deep-sea environment, seamounts typically form biological hotspots with a distinct, abundant and diverse fauna, many species of which remain unidentified. Consequently, the fauna of seamounts is usually highly unique and may have a limited distribution restricted to a single geographic region, a seamount chain or even a single seamount location (Rogers et al. 2008). Levels of endemism on seamounts are also relatively high compared to the deep sea. As a result of conservative life histories (i.e. very slow growing, slow to mature, high longevity, low levels of recruitment) and sensitivity to changes in environmental conditions, such biological communities have been identified as Vulnerable Marine Ecosystems (VMEs). They are recognised as being particularly sensitive to anthropogenic disturbance (primarily deep-water trawl fisheries and mining), and once damaged are very slow to recover, or may never recover (FAO 2008).

It is not always the case that seamount habitats are VMEs, as some seamounts may not host communities of fragile animals or be associated with high levels of endemism. Evidence from video footage taken on hard-substrate habitats in 100 - 120 m depth off southern Namibia (Figure 10) suggest that vulnerable communities including gorgonians, octocorals and reef-building sponges occur on the continental shelf, and similar communities may thus be expected on the seamounts associated with the Walvis Ridge.

Figure 10: Gorgonians and bryozoans communities recorded on deep-water reefs (100-120 m) off

the southern African West Coast (Photos: De Beers Marine).



3.3.3 Pelagic Communities

The pelagic communities are typically divided into plankton and fish, and their main predators, marine mammals (seals, dolphins and whales), seabirds and turtles.

3.3.3.1 Plankton

Plankton is particularly abundant in the shelf waters off Namibia, being associated with the upwelling characteristic of the area. Plankton range from single-celled bacteria to jellyfish of 2-m diameter, and include bacterio-plankton, phytoplankton, zooplankton, and ichthyoplankton (Figure 11). Figure 11: Phytoplankton (left, photo: hymagazine.com) and zooplankton (right, photo:

mysciencebox.org) is associated with upwelling cells.

Off the Namibian coastline, phytoplankton are the principle primary producers with mean annual productivity being comparatively high at 2 g C/m2/day (Barnard 1998). The phytoplankton is dominated by diatoms, which are adapted to the turbulent sea conditions. Diatom blooms occur after upwelling events, whereas dinoflagellates are more common in blooms that occur during quiescent periods, since they can grow rapidly at low nutrient concentrations. In the surf zone, diatoms and dinoflagellates are nearly equally important members of the phytoplankton, and some silicoflagellates are also present.

Namibian zooplankton reaches maximum abundance in a belt parallel to the coastline and offshore of the maximum phytoplankton abundance. Samples collected over a full seasonal cycle (February to December) along a 10 to 90-nautical-miles transect offshore Walvis Bay showed that the mesozooplankton (<2 mm body width) community included egg, larval, juvenile and adult stages of copepods, cladocerans, euphausiids, decapods, chaetognaths, hydromedusae and salps, as well as protozoans and meroplankton larvae (Maartens 2003; Hansen et al. 2005). Copepods are the most dominant group making up 70–85% of the zooplankton. Seasonal patterns in copepod abundance, with low numbers during autumn (March–June) and increasing considerably during winter/early summer (July–December), appear to be linked to the period of strongest coastal upwelling in the northern Benguela (May–December), allowing a time lag of about 3–8 weeks, which is required for copepods to respond and build up large populations (Hansen et al. 2005). This suggest close coupling between hydrography, phytoplankton and zooplankton. Timonin et al. (1992) described three phases of



the upwelling cycle (quiescent, active and relaxed upwelling) in the northern Benguela, each one characterised by specific patterns of zooplankton abundance, taxonomic composition and inshore-offshore distribution. It seems that zooplankton biomass closely follows the changes in upwelling intensity and phytoplankton standing crop. Consistently higher biomass of zooplankton occurs offshore to the west and northwest of Walvis Bay (Barnard 1998).

Ichthyoplankton constitutes the eggs and larvae of fish. As the preferred spawning grounds of numerous commercially exploited fish species are located off central and northern Namibia (Figure 12), their eggs and larvae form an important contribution to the ichthyoplankton in the region. Phytoplankton, zooplankton and ichthyoplankton abundances in the survey area will be seasonally high, with diversity increasing in the in the vicinity of the confluence between the Angola and Benguela currents and west of the oceanic front and shelf-break.

Figure 12: The proposed survey area in relation to major spawning areas in the central and northern

Benguela region (adapted from Cruikshank 1990; Hampton 1992).



3.3.3.2 Pelagic Invertebrates

Pelagic invertebrates that may be encountered in the project area are the colossal squid Mesonychoteuthis hamiltoni and the giant squid Architeuthis sp. Both are deep dwelling species, with the colossal squid’s distribution confined to the entire circum-antarctic Southern Ocean (Figure 13, left) while the giant squid is usually found near continental and island slopes all around the world’s oceans (Figure 13, right). Both species could thus potentially occur in the pelagic habitats of the project area, although the likelihood of encounter is extremely low. Growing to in excess of 10 m in length, they are the principal prey of the sperm whale, and are also taken by beaked whaled, pilot whales, elephant seals and sleeper sharks. Nothing is known of their vertical distribution, but data from trawled specimens and sperm whale diving behaviour suggest they may span a depth range of 300 – 1,000 m. They lack gas-filled swim bladders and maintain neutral buoyancy through an ammonium chloride solution occurring throughout their bodies. Figure 13: Distribution of the colossal squid (left) and the giant squid (right) (www.wikipedia.org).

3.3.3.3 Fish

Small pelagic species include the sardine/pilchard (Sadinops ocellatus) (Figure 13, left), anchovy (Engraulis capensis), chub mackerel (Scomber japonicus), horse mackerel (Trachurus capensis) (Figure 13, right) and round herring (Etrumeus whiteheadi). These species typically occur in mixed shoals of various sizes (Crawford et al. 1987), and generally occur within the 200 m contour, although they may often be found very close inshore, just beyond the surf zone. They spawn downstream of major upwelling centres in spring and summer, and their eggs and larvae are subsequently carried up the coast in northward flowing waters. Historically, two seasonal spawning peaks for pilchard occurred; the first from October to December in an inshore area between Walvis Bay and Palgrave Point and the second from February to March near the 200 m isobath between Palgrave Point and Cape Frio. However, since the collapse of the pilchard stock, spawning in the south has decreased (Crawford et al. 1987 in Boyer & Hampton, 2001). Recruitment success relies on the interaction of oceanographic events, and is thus subject to spatial and temporal variability. Consequently, the abundance of adults and juveniles of these small pelagic fish is highly variable both within and between species. The Namibian pelagic stock is currently considered to be in a critical condition due to a combination of over-fishing and unfavourable environmental conditions as a result of Benguela Niños.



Figure 13: Cape fur seal preying on a shoal of pilchards (left). School of horse mackerel (right)

(photos: www.underwatervideo.co.za; www.delivery.superstock.com).

Two species that migrate along the southern African West Coast following the shoals of

anchovy and pilchards are snoek Thyrsites atun and chub mackerel Scomber japonicas. Their appearance along the Namibian coast are highly seasonal. Snoek are voracious predators occurring throughout the water column, feeding on both demersal and pelagic invertebrates and fish. The abundance and seasonal migrations of chub mackerel are thought to be related to the availability of their shoaling prey species (Payne & Crawford 1989).

Large pelagic species include tunas, billfish and pelagic sharks, which migrate throughout the southern oceans, between surface and deep waters (>300 m) and have a highly seasonal abundance in the Benguela. Species occurring off Namibia include the albacore/longfin tuna Thunnus alalunga (Figure 14, right), yellowfin T. albacares, bigeye T. obesus, and skipjack Katsuwonus pelamis tunas, as well as the Atlantic blue marlin Makaira nigricans (Figure 14, left), the white marlin Tetrapturus albidus and the broadbill swordfish Xiphias gladius (Payne & Crawford 1989). The distributions of these species is dependent on food availability in the mixed boundary layer between the Benguela and warm central Atlantic waters. Concentrations of large pelagic species are also known to occur associated with underwater feature such as canyons and seamounts as well as meteorologically induced oceanic fronts (Penney et al. 1992). Figure 14: Large migratory pelagic fish such as blue marlin (left) and longfin tuna (right) occur in

offshore waters (photos: www.samathatours.com; www.osfimages.com).



A number of species of pelagic sharks are also known to occur off the southern African West Coast, including blue Prionace glauca, short-fin mako Isurus oxyrinchus and oceanic whitetip sharks Carcharhinus longimanus. Occurring throughout the world in warm temperate waters, these species are usually found further offshore. Of these the blue shark is listed as “Near threatened”, and the short-fin mako, whitetip, great white and whale sharks as “Vulnerable” on the International Union for Conservation of Nature (IUCN).

The inshore waters of the central and northern Namibian coastline are also home to a number of boney fish and cartilagenous fish, many of which are popular angling species. These include the Silver kob Argyrosomus inodorus, dusky kob Argyrosomus coronus, white steenbras Lithognathus lithognathus, west coast steenbras Lithognathus aureti, copper shark Carcharhinus brachyurus, the spotted gulley shark Triakis megalopterus and the smoothhound Mustelus mustelus (Kirchner et al. 2000; Zeybrandt & Barnes 2001). Warm water species that occur further north include garrick Lichia amia, shad Pomatomus saltatrix and spotted grunter Pomadasys jubelini (Barnard 1998).

Spawning in silver kob occurs throughout the year but mostly in the warmer months from October to March when water temperatures are above 15°C and large adult fish occur in the nearshore, particularly in the identified spawning areas of Sandwich Harbour and Meob Bay. Adults are migratory whereas juveniles are resident in the surf zone. The stock is exploited by the commercial linefishery (deck and skiboats) and recreational shore angling and is regarded as overexploited and near collapse with less than 25% of pristine spawner biomass remaining (Kirchner 2001; Holtzhausen et al. 2001). The juveniles and adolescents of dusky kob are resident in the nearshore, and are especially abundant in the turbid plume off the Cunene River Mouth and in selected surf zones of northern and central Namibia (Potts et al. 2010). The adults are migratory according to the movement of the Angola-Benguela frontal zone, moving northwards as far as Gabon in winter and returning to southern Angola and northern Namibia in spring where spawning occurs in the offshore (Potts et al. 2010). The bulk of the population of both steenbrass species exists in the nearshore at <10 m depth, with juveniles occurring in the intertidal surf zone. Spawning occurs in the surf zone and eggs and larvae from both populations drift northwards (Holtzhausen 2000). Spawning habitats are thought to be extremely limited and have yet to be clearly identified. 3.3.3.4 Turtles

Five of the eight species of turtle worldwide occur off Namibia (Bianchi et al. 1999). The Leatherback (Dermochelys coriacea) (Figure 15) is the only turtle likely to be encountered regularly in the offshore waters off Namibia. The Benguela ecosystem, especially the northern Benguela where jelly fish numbers are high, is increasingly being recognized as a potentially important feeding area for leatherback turtles from several globally significant nesting populations in the south Atlantic (Gabon, Brazil) and south east Indian Ocean (South Africa) (Lambardi et al. 2008, Elwen & Leeney 2011). Leatherback turtles from the east South Africa population have been satellite tracked swimming around the west coast of South Africa and remaining in the warmer waters west of the Benguela ecosystem (Lambardi et al. 2008).

Leatherback turtles inhabit deeper waters and are considered a pelagic species, travelling the ocean currents in search of their prey. While hunting they may dive to over 600 m and remain submerged for up to 54 minutes (Hays et al. 2004), thus making them difficult to observe from the surface and susceptible to seismic operations. Their abundance in the study area is unknown but expected to be low.



Figure 15: Leatherback (left) and loggerhead turtles (right) occur along the coast of Central

Namibia (Photos: Ketos Ecology 2009; www.aquaworld-crete.com).

Although they tend to avoid nearshore areas, they may be encountered in Walvis Bay and

off Swakopmund between October and April when prevailing north wind conditions result in elevated seawater temperatures (Figure 16). Leatherback turtles have recently washed up in significant numbers on the central Namibian shore. During the past five years 200 to 300 dead turtles were found (www.nacoma.org.na). Leatherbacks feed on jellyfish and are known to have mistaken plastic bags, raw plastic pellets, plastic and styrofoam, tar balls and balloons for their natural food. Ingesting this debris can obstruct the gut, lead to absorption of toxins and reduce the absorption of nutrients from their real food. The turtles also get entangled in fishing gear and drown.

Observations of Green (Chelonia mydas), Loggerhead (Caretta caretta), Hawksbill (Eretmochelys imbricata) and Olive Ridley (Lepidochelys olivacea) turtles in the area are rare. Figure 16: The project area (red polygon) in relation to the post-nesting distribution of nine

satellite tagged leatherback females (1996 – 2006; Oceans and Coast, unpublished data).



3.3.3.5 Seabirds

The Namibian coastline sustains large populations of breeding and foraging seabird and shorebird species, which require suitable foraging and breeding habitats for their survival. In total, 11 species of seabirds are known to breed along the southern Namibian coast (Table 1). Most seabirds breeding in Namibia are restricted to areas where they are safe from land predators, although some species are able to breed on the mainland coast in inaccessible places. In general most breed on the islands off the southern Namibian coast, or on the man-made guano platforms in Walvis Bay, Swakopmund and Cape Cross. The southern Namibian islands and guano platforms therefore provide a vital breeding habitat to most species of seabirds that breed in Namibia (Figure 17). However, the number of successfully breeding birds at the particular breeding sites varies with food abundance (J. Kemper, MFMR Lüderitz, pers. comm.). With the exception of Kelp Gull all the breeding species are listed Red Data species in Namibia.

Most of the seabird species breeding in Namibia feed relatively close inshore (10-30 km). Cape Gannets, however, are known to forage up to 140 km offshore (Dundee 2006; Ludynia 2007), and African Penguins have also been recorded as far as 60 km offshore.

Other Red-listed species found foraging, or roosting along the coastline of southern Namibia are listed in Table 1. Among the species present there are five species of albatrosses, petrels or giant-petrels recorded in the waters off Namibia’s southern coast (Boyer & Boyer, in press). However, population numbers are poorly known and they do not breed in Namibian waters.

Forty-nine species of pelagic seabirds have been recorded in the region, of which 14 are resident. Highest pelagic seabird densities occur offshore of the shelf-break in winter. Figure 17: Cape Gannets Morus capensis (left) (Photo: NACOMA) and African Penguins Spheniscus

demersus (right) (Photo: Klaus Jost) breed primarily on the offshore Islands.



Table 1: Southern Namibian breeding seabird species with their Namibian and global IUCN Red-

listing classification (from Kemper et al. 2007; Simmons & Brown in press).

SPECIES Namibian Global IUCN

African Penguin Spheniscus demersus Endangered Vulnerable

Bank Cormorant Phalacrocorax neglectus Endangered Endangered

Cape Cormorant Phalacrocorax capensis Near Threatened Near Threatened

Cape Gannet Morus capensis Endangered Vulnerable

Crowned Cormorant Phalacrocorax coronatus Near Threatened Least Concern

African Black Oystercatcher Haematopus moquini Near Threatened Near Threatened

White-breasted cormorant Phalacrocorax carbo Least Concern Least Concern

Kelp Gull Larus dominicanus Least Concern Least Concern

Hartlaub's Gull Larus hartlaubii Vulnerable Least Concern

Swift Tern Sterna bergii bergii Vulnerable Least Concern

Damara Tern Sterna balaenarum Near Threatened Near Threatened


global classifications are the result of local population size, and the extent and duration of declines locally. 1. May move to Critically Endangered if mortality from long-lining does not decrease.

In central Namibia, the 30 km long shoreline between Walvis Bay and Swakopmund has the highest linear count of birds in southern Africa at ~450 birds/km with totals exceeding 13,000 shorebirds of 31 species, most of which are Palearctic migrants (Simmons et al. 1999; Molloy & Reinikainen 2003; http://www.ramsar.org/profile/profiles_namibia .htm). Individual 10 km sections, peak even higher at 770 birds/km. Birds reported from the 30 km stretch of coast between Walvis Bay and Swakopmund include African Black Oystercatcher, Kelp Gull, Cape cormorant, Turnstone (Arenaria interpres), Curlew Sandpiper (Calidris ferruginea), Grey plover (Pluvialis squatarola), Swift Tern, Damara tern and Common Tern (Sterna hirundo) (Simmons et al. 1999).

The coastline between Walvis Bay and Cape Cross also boasts three man-made guano platforms: “Bird Rock” north of Walvis Bay is 200 m offshore, whereas those north of Swakopmund and at Cape Cross have been erected in salt pans. The platforms are unique in the world, and currently produce about 2,500 tons of guano per season. About 99% of the birds occurring on the platforms are Cape Cormorants, although Whitebreasted Cormorants, Crowned Cormorants and Great White Pelicans also breed on the platforms (http://www.namibweb. com/guano.htm; http://web.uct.ac.za/depts/stats/adu/walvisbay guano platform.htm).

The Kunene River mouth and its estuary at the border with Angola also serves as an extremely important wetland for coastal birds, particularly the near threatened Damara Tern, which has been recorded in high numbers (2,000 – 5,000) within and to the south of the mouth.



Table 2: Other Namibian Red-listed bird species with their Namibian and global IUCN Red-listing

classification (from Kemper et al. 2007; Simmons & Brown in press).

SPECIES Namibian Global IUCN

Atlantic Yellow-nosed Albatross Thalassarche chlororhynchos Endangered Endangered1

Black-browed Albatross Thalassarche melanophrys Endangered Endangered

Caspian Tern Sterna caspia Vulnerable Vulnerable

Greater Flamingo Phoenicopterus ruber Vulnerable Near Threatened

Lesser Flamingo Phoenicopterus minor Vulnerable Near Threatened

White-chinned Petrel Procellaria aequinoctialis Vulnerable Vulnerable

Chestnut-banded Plover Charadrius pallidus Near Threatened Least Concern

Northern Giant-Petrel Macronectes halli Near Threatened Near Threatened

Shy Albatross Thalassarche cauta Near Threatened Near Threatened


global classifications are the result of local population size, and the extent and duration of declines locally. 1. May move to Critically Endangered if mortality from long-lining does not decrease.

3.3.3.6 Marine Mammals

Marine mammals occurring off the Namibian coastline include cetaceans (whales and dolphins) and seals. The cetacean fauna of the Namibia comprises 32 species of whales and dolphins known (historic sightings or strandings) or likely (habitat projections based on known species parameters) to occur here (Table 3). Apart from the resident species such as the endemic Heaviside’s dolphin, bottlenose and dusky dolphins, Namibia’s waters also host species that migrate between Antarctic feeding grounds and warmer breeding ground waters, as well as species with a circum-global distribution. The proposed survey area lies close to the northern boundary of the cool Benguela ecosystem and predominantly pelagic habitat from the edge of the continental shelf to more than 4,000 m depth. Both cetacean species associated with the Benguela ecosystem (e.g. dusky dolphins) and those associated with the warmer sub-tropical habitat off Angola are likely to be encountered in the survey area. The Namibian shelf and deeper waters has been poorly studied with most available information in deeper waters (>200 m) arising from historic whaling records, although data from marine mammal observers and passive acoustic monitoring is improving knowledge in recent years. Current information on the distribution, population sizes and trends of most cetacean species occurring in Namibian waters is lacking. Information on smaller cetaceans in deeper waters (>100 m) is particularly poor and the precautionary principal must be used when considering possible encounters with cetaceans in this area.

The distribution of cetaceans in Namibian waters can largely be split into those associated with the continental shelf and those that occur in deep, oceanic water. Importantly, species from both environments may be found in the shelf edge area (200-1,000 m) making this the most species-rich area for cetaceans. Cetacean density on the continental shelf is usually higher than in pelagic waters as species associated with the pelagic environment tend to be wide ranging across 1,000s of km. The most common species within the projected survey area (in terms of likely encounter rate not total population sizes) are likely to be the humpback whale and pilot whale.



Table 3: List of cetacean species known (from historic sightings or strandings) or likely (habitat projections based on known species parameters) to occur

in Namibian waters. Likely occurrence in probable habitat (Shelf or Offshore) is indicated by ‘yes’, ‘no’ (unlikely), ‘edge’ (shelf edge 200-500

m depth) or ‘?’ (unknown).

Common Name Species Shelf Offshore Seasonality IUCN Conservation Status

Delphinids

Dusky dolphin Lagenorhynchus obscurus Yes (0- 800 m) No Year round Least Concern

Heaviside’s dolphin Cephalorhynchus heavisidii Yes (0-200 m) No Year round Least Concern

Common bottlenose dolphin Tursiops truncatus Yes Yes Year round Least Concern

Common (short beaked) dolphin Delphinus delphis Yes Yes Year round Least Concern

Southern right whale dolphin Lissodelphis peronii Yes Yes Year round Data Deficient

Striped dolphin Stenella coeruleoalba No Yes Year round Least Concern

Long-finned pilot whale Globicephala melas Edge Yes Year round Data Deficient

Short-finned pilot whale Globicephala macrorhynchus No Yes Year round Data Deficient

Rough-toothed dolphin Steno bredanensis No Yes Year round Least Concern

Killer whale Orcinus orca Yes Yes Year round Data Deficient

False killer whale Pseudorca crassidens Occasional Yes Year round Data Deficient

Pygmy killer whale Feresa attenuata Occasional Yes Year round Data Deficient

Risso’s dolphin Grampus griseus Yes (edge) Yes ? Least Concern

Sperm whales

Pygmy sperm whale Kogia breviceps Edge Yes Year round Data Deficient

Dwarf sperm whale Kogia sima Edge ? ? Data Deficient

Sperm whale Physeter macrocephalus Edge Yes Year round Vulnerable



Common Name Species Shelf Offshore Seasonality IUCN Conservation Status

Beaked whales

Cuvier’s Ziphius cavirostris No Yes Year round Least Concern

Arnoux’s Beradius arnouxii No Yes Year round Data Deficient

Southern bottlenose Hyperoodon planifrons No Yes Year round Not assessed

Layard’s Mesoplodon layardii No Yes Year round Data Deficient

True’s M. mirus No Yes Year round Data Deficient

Gray’s M. grayi No Yes Year round Data Deficient

Blainville’s M. densirostris No Yes Year round Data Deficient

Baleen whales


Dwarf minke B. acutorostrata Yes Yes Year round Least Concern

Fin whale B. physalus Yes Yes MJJ & ON, rarely in

summer

Endangered

Blue whale B. musculus No Yes Higher in MJJ Endangered

Sei whale B. borealis Edge Yes MJ & ASO Endangered

Bryde’s (offshore) B. brydei Yes Yes Higher in Summer (JFM) Not assessed

Pygmy right Caperea marginata Yes ? Year round Data Deficient

Humpback Megaptera novaeangliae Yes Yes Year round, higher in

JJASON

Least Concern

Southern right Eubalaena australis Yes No Year round, higher in

JASON

Least Concern



Cetaceans comprise two basic taxonomic groups, the mysticetes (filter feeding whales with baleen) and the odontocetes (predatory whales and dolphins with teeth). The term ‘whale’ is used to describe cetaceans larger than approximately 4 m in length, in both these groups and is taxonomically meaningless (e.g. the killer whale and pilot whale are members of the Odontocetes and the family Delphinidae and are thus dolphins, not whales). Due to large differences in their size, sociality, communication abilities, ranging behavior and principally, acoustic behavior, these two groups are considered separately.

Table 3 lists the cetaceans likely to be found within the survey area (Findlay et al. 1992; Best 2007; J-P. Roux, pers. comm; NDP unpublished data). Of the 32 species listed, three are endangered and one is considered vulnerable. Altogether 17 species are listed as “data deficient”, underlining how little is known about cetaceans, their distributions and population trends in Namibian waters. A review of the distribution of the key cetacean species is provided below.

The term ‘survey area’ is used to define the survey area and region surrounding this that is likely to be affected by the increased shipping and noise levels associated with airgun activities. Exact definitions of the survey area are not possible as sound propagation modelling has not taken place in the survey area and distribution of many species is poorly understood, therefore we use this term in a broad sense to encompass the species and region likely to be most affected by seismic activities.

Mysticete (Baleen) whales

The majority of mysticetes whales fall into the family Balaenidae. Those occurring in the study area include the blue, fin, sei, Antarctic minke, dwarf minke, humpback and Bryde’s whale (see Table 3 for scientific names). The majority of these species occur in pelagic waters with only the occasional visit to shelf waters. All of these species show some degree of migration either to, or through the latitudes encompassed by the proposed survey zone when en route between higher latitude (Antarctic or Subantarctic) feeding grounds and lower latitude breeding grounds. Depending on the ultimate location of these feeding and breeding grounds, seasonality in Namibian waters can be either unimodal, usually in winter months, or bimodal (e.g. May-July and October-November) reflecting a northward and southward migration through the area. Northward and southward migrations may take place at different distances from the coast due to whales following geographic or oceanographic features, thereby influencing the seasonality of occurrence at different locations. Due to the complexities of the migration patterns, each species is discussed in further detail below.

There is very little information on sei whales in Namibian waters and most information on the species from the southern African sub-region originates from whaling data from 1958-1963. Sei whales spend time at high altitudes (40-50˚S) during summer months and migrate north through South African waters (where they were historically hunted in relatively high numbers) to unknown breeding grounds further north (Best 2007). As whaling catches were confirmed off both Congo and Angola, it is likely that they migrate through Namibian waters. Due to their migration pattern, densities in the proposed survey area are likely to show a bimodal peak with numbers predicted to be highest in May and June, and again in August, September, and October. All whales were historically caught in waters deeper than 200 m with most catches from deeper than 1,000 m (Best & Lockyer 2002). There is no current information on the abundance or distribution of this species in the region, but a recent sighting of a mother and calf in March 2012 (NDP unpublished data) and a stranding in Walvis Bay in July 2013 (NDP



unpublished data) confirms their contemporary and probably year round occurrence on the Namibian continental shelf and beyond. Encounters in the survey area are likely to occur.

Two genetically and morphologically distinct populations of Bryde’s whales live off the west coast of southern Africa (Best 2001; Penry 2010). The “offshore population” lives beyond the shelf (>200 m depth) off west Africa and migrates between wintering grounds off equatorial west Africa (Gabon) and summering grounds off western South Africa. Its seasonality on the west coast is thus opposite to the majority of the balaenopterids with abundance likely to be highest in the broader potential survey area in January - March. A stranding of an adult offshore Bryde’s whales in January 2012 in Walvis Bay, Namibia (population assigned genetically – G Penry pers. comm.) confirms the population's current occurrence in central Namibia. The “inshore population” of Bryde’s whales is unique amongst baleen whales in the region by being non-migratory. The published range of the population is the continental shelf and Agulhas Bank of South Africa ranging from Durban in the east to at least St Helena Bay off the west coast with possible movements further north into the winter months (Best 2007). A live stranding of a calf of this population (population assigned genetically – G Penry pers. comm.) in Walvis Bay, Namibia confirms the current occurrence of this population in Namibian waters. An additional third stranding of a Bryde’s whale adult in April 2013 has not yet been assigned to population but indicates regular, year round occurrence of the species in Benguela waters (NDP unpubl. data). Encounters in the survey area are likely to occur.

Fin whales were historically caught off the coast of Namibia. A bimodal peak in the catch data from South Africa suggests animals were migrating further north to breed (during May-July) before returning to Antarctic feeding grounds (during October-November). Recent data available from passive acoustic monitoring over a two-year period off the Walvis Ridge shows acoustic presence in June-August (Thomisch et al. 2016), supporting observations from whaling records. The location of the breeding ground (if any) and how far north it is, is unknown (Best 2007). Some juvenile animals may feed year round in deeper waters off the shelf (Best 2007). Four strandings have occurred in between Walvis Bay and the Kunene River in the last decade (NDP unpubl. data) and groups of 5-8 animals have been seen on multiple occasions on the coast either side of Lüderitz in April, May of 2014 and January 2015 (NDP unpubl. data) confirming their contemporary occurrence in Namibian waters and potential use of the upwelling areas for feeding. Encounters in the survey area may occur.

Antarctic blue whales were historically caught in high numbers during commercial whaling activities, with a single peak in catch rates during July in Walvis Bay, Namibia and Namibe, Angola suggesting that in the eastern South Atlantic these latitudes are close to the northern migration limit for the species (Best 2007). Only two published sightings of blue whales have occurred off the entire west coast of Africa since 1973 (Branch et al. 2007), although search effort (and thus information) in Namibia and in pelagic waters is very low. Recent acoustic detections of blue whales in the Antarctic peak between December and January (Tomisch et al. 2016) and in northern Namibia between May and July (Thomisch et al. 2016) supporting observed timing from whaling records. Several recent (2014-2015) sightings of blue whales have occurred during seismic surveys off the southern part of Namibia in water >1,000m deep confirming their current existence in the area and occurrence in Autumn months. Encounters in the survey area may occur.

Two forms of minke whale occur in the southern Hemisphere, the Antarctic minke whale and the dwarf minke whale; both species occur in the Benguela (Best 2007; NDP unpubl. data). Antarctic minke whales range from the pack ice of Antarctica to tropical waters and are usually



seen more than ~50 km offshore. Although adults of the species do migrate from the Southern Ocean (summer) to tropical/temperate waters (winter) where they are thought to breed, some animals, especially juveniles, are known to stay in tropical/temperate waters year round. Regular sightings of semi-resident Antarctic minke whales in Lüderitz Bay, especially in summer months (December - March) and a stranding of a single animal in Walvis Bay (in February 2014) confirm the contemporary occurrence of the species in Namibia (NDP unpubl. data). Recent data available from passive acoustic monitoring over a two-year period off the Walvis Ridge shows acoustic presence in June - August and November - December (Thomisch et al. 2016), supporting observations from whaling records. The dwarf minke whale has a more temperate distribution than the Antarctic minke and they do not range further south than 60-65°S. Dwarf minke whales have a similar migration pattern to Antarctic minkes with at least some animals migrating to the Southern Ocean in summer months. Around southern Africa, dwarf minke whales occur closer to shore than Antarctic minkes and have been seen <2 km from shore on several occasions around South Africa. Both species are generally solitary and densities are likely to be low in the impact area, but encounters may occur.

The pygmy right whale is the smallest of the baleen whales reaching only 6 m total length as an adult (Best 2007). The species is typically associated with cool temperate waters between 30°S and 55°S and records in Namibia are the northern most for the species with no confirmed records north of Walvis Bay, so it is unlikely to occur in the impact area.

The most frequently encountered baleen whales off the coast of Namibia are southern right and humpback whales (Figure 18). In the last decade, both southern right whales and humpback whales have been increasingly observed to remain on the West Coast of South Africa well after the typical South African 'whale season' of June-November, sometimes staying as late as February where they have been observed feeding in upwelling zones, especially Saldanha and St Helena Bays on the west coast of South Africa (Barendse et al. 2011; Mate et al. 2011). In Namibian waters, humpback whales have similarly been seen ‘out of season’ (i.e. March-April; NDP unpublished data) and southern right whales have also been sighted in all months of the year (J-P. Roux, pers. comm). This suggests that these species have a year round occurrence in Namibian waters, with a peak in late winter months associated with the annual migration of the majority of the populations.

Figure 18: The Southern Right whale Eubalaena australis (left) and the humpback whale Megaptera

novaeangliae (right) migrate along the coastal and shelf waters of southern Africa,

including Namibia (Photos: www.NamibianDolphinProject.com).



The southern African southern right whale population historically extended from southern Mozambique to southern Angola and is considered to be a single population within this range. The most recent abundance estimate available puts the population at approximately 4,600 individuals of all age and sex classes in 2008, which is thought to be at least 23% of the original population size (Brandaõ et al. 2011). Since the population is still continuing to grow at ~7% per year (Brandaõ et al. 2011), the population size in 2016 would number more than 8,000 individuals. The population range contracted when the population crashed, but as it recovers animals are repopulating historic grounds including Namibia and distribution patterns near the ranges ends are dynamic and unpredictable. Southern right whales have been seen regularly in Namibian coastal waters, and are more common along the southern Namibian coastline between Conception Bay and Chameis Bay, although some have been reported as far north as the Kunene and Möwe Bay (Roux et al. 2015). All reported sightings have been within 3 km of shore which is consistent with known distribution patterns around South Africa. Right whales have been recorded in Namibian waters in all months of the year (J-P. Roux, pers. comm., NDP unpublished data) but with numbers peaking during the calving season in winter (June-September) (Best 1994; Roux et al. 2001). A secondary peak in summer (December-January) also occurs, possibly associated with animals feeding off the west coast of South Africa performing exploratory trips into southern Namibia (NDP unpubl. data). Animals photographed in Namibia have recently been shown to be a part of the southern African population, which breeds predominantly off the southern Cape coast (Roux et al. 2015). Although most right whales are thought to hug the shore when around southern Africa, it has recently been proposed based on a review of historic whaling data and sightings in Namibian water that some animals may be foraging in the upwelling cells of the Benguela ecosystem, which reach up to 200 km from shore (Roux et al. 2015). Due to the distance from shore and low latitude of the survey area, encounters with southern right whales are unlikely to occur.

The majority of humpback whales passing through the Benguela are migrating to breeding grounds off equatorial west Africa, between Angola and the Gulf of Guinea (Rosenbaum et al. 2009; Barendse et al. 2010). A recent synthesis of available humpback whale data from Namibia (Elwen et al. 2014) shows that in coastal waters, the northward migration stream is larger than the southward peak supporting earlier observations from whale catches (Best & Allison 2010). This supports previous suggestions that animals migrating north strike the coast at varying places mostly north of St Helena Bay (South Africa) resulting in increasing whale density on shelf waters moving north towards Angola, but no clear migration ‘corridor’. So humpback whales appear to be spread out widely across the shelf and into deeper pelagic waters (Barendse et al. 2010; Best & Allison 2010; Elwen et al. 2014). There is evidence from satellite tagged animals and the smaller secondary peak in numbers in Walvis Bay, that many humpback whales on their southern migration follow a more offshore route along the Walvis Ridge, which is directly across the impact area, while others follow a more coastal route (including the majority of mother-calf pairs) possibly lingering in the feeding grounds off West South Africa in summer (Elwen et al. 2014; Rosenbaum et al. 2014). Recent abundance estimates put the number of animals in the west African breeding population to be in excess of 9,000 individuals in 2005 (IWC 2012) and it is likely to have increased since this time at about 5% per annum (IWC 2012). Humpback whales are thus likely to be the most frequently encountered baleen whale in the impact site, ranging from the coast out beyond the shelf, with year round presence but numbers peaking in July – October associated with the breeding migration. It is important to note that mother-calf pairs are usually the the last animals to



migrate away from calving grounds and thus pass through Namibian waters. Although these animals often stay close to shore, they are still likely to be the dominant social class observed from September onwards in Namibian waters. Travelling baleen whales and especially mother-calf groups tend to be acoustically quiet (possibly to minimise detection by killer whales) and are thus very challenging to detect at night even with the implementation of Passive Acoustic Monitoring (PAM). Humpback whales are the most likely baleen whale to be encountered.

Odontocete (toothed) whales

The Odontoceti are a varied group of animals including the dolphins, porpoises, beaked whales and sperm whales. Species occurring within the broader survey area display a diversity of features, for example their ranging patterns vary from extremely coastal and highly site specific to oceanic and wide ranging. Those in the region can range in size from 1.6 m long (Heaviside’s dolphin) to 17 m (bull sperm whale).

All information about sperm whales in the southern African subregion stems from data collected during commercial whaling activities, i.e. pre 1985 (Best 2007). Sperm whales are the largest of the toothed whales and have a complex, structured social system with adult males behaving differently to younger males and female groups. They live in deep ocean waters, usually greater than 1,000 m depth, although they occasionally come into waters 500-200 m deep on the shelf (Best 2007). They are relatively abundant globally (Whitehead 2002), although no estimates are available for the southern African subregion. Seasonality of catches off west South Africa suggests that medium and large sized males are more abundant in winter months, while female groups are more abundant in autumn (March-April), although animals occur year round (Best 2007). Sperm whales were one of the most frequently seen cetacean species during a series of observations made from offshore seismic survey vessels operating between Angola and the Gulf of Guinea. All sightings were made in water deeper than 780 m, and numbers peaked during April – June (Weir 2011). In contrast, sightings of sperm whales by Marine Mammal Observers (MMOs) on seismic vessels operating in Namibia are low. Sperm whales feed at great depths during dives in excess of 30 minutes making them difficult to detect visually. The regular echolocation clicks made by the species when diving, however, make them relatively easy to detect acoustically using PAM. The proposed survey should be largely inshore of the expected range of sperm whales and sightings in the survey area are expected to be very low.

There are almost no data available on the abundance, distribution, or seasonality of the smaller odontocetes (including the beaked whales and dolphins) known to occur in oceanic waters (greater than 200 m) off the Namibian continental shelf (see Table 3). Beaked whales are all considered to be true deep-water species, usually recorded in waters in excess of 1,000 – 2,000 m (see various species accounts in Best 2007) and thus may be encountered in the proposed survey area.

Beaked whales seem to be particularly susceptible to man-made sounds and several strandings and deaths at sea, often en masse, have been recorded in association with naval mid-frequency sonar (Cox et al. 2006, MacLeod & D’Amico, 2006) and a seismic survey for hydrocarbons also running a multi-beam echo-sounder and sub bottom profiler (Cox et al. 2006). Although the exact reason that beaked whales seem particularly vulnerable to man-made noise is not yet fully understood, the existing evidence clearly shows that animals change their dive behaviour in response to acoustic disturbance (Tyack et al. 2011), and all possible precautions should be taken to avoid causing any harm. The proposed survey should be largely



inshore of the expected range of sperm whales and sightings in the survey area are expected to be very low.

The genus Kogia currently contains two recognised species, the dwarf (K. sima) and

pygmy (K. breviceps) sperm whales. Both species are deep water specialists living primarily off the shelf. There is preliminary evidence of species level genetic differentiation between K. sima populations in the Indian and Atlantic Oceans (Chivers et al. 2004). Due to their small body size, cryptic behaviour and small school sizes, these whales are difficult to observe at sea, and morphological similarities make field identification to species level problematic. The majority of what is known about Kogiid whales in the southern African subregion results from studies of stranded specimens (e.g. Ross 1979; Findlay et al. 1992; Plön 2004). There are >30 records of K. breviceps collected along the Namibian coastline with a peak in strandings in June and August. A single account of K. sima collected in Walvis Bay in 2010, demonstrates that this species also occurs in Namibian waters (Elwen et al. 2014) and as a warm-water specialist is likely to occur within the impact area.

Killer whales have a circum-global distribution being found in all oceans from the equator to the ice edge (Best 2007). Killer whales occur year round in low densities off western South Africa (Best et al. 2010), Namibia (Elwen & Leeney 2011) and in the Eastern Tropical Atlantic (Weir et al. 2010). Killer whales are found in all depths from the coast to deep open ocean environments and may thus be encountered in the impact area at low levels.

False killer whales are recognized as a single species globally, although clear differences in morphological and genetic characteristics between different study sites show that there is substantial difference between populations and a revision of the species taxonomy may be needed (Best 2007). The species has a tropical to temperate distribution and most sightings off southern Africa have occurred in water deeper than 1000 m but with a few close to shore as well (Findlay et al. 1992; NDP Unpubl. data). False killer whales usually occur in groups ranging in size from 1-100 animals (mean 20.2) (Best 2007), and are thus likely to be fairly easily seen in most weather conditions. However, the strong bonds and matrilineal social structure of this species makes it vulnerable to mass stranding (8 instances of 4 or more animals stranding together have occurred in the western Cape, South Africa, all between St Helena Bay and Cape Agulhas), which may aggrandize the consequences of any injury or disturbance by seismic airguns or associated activities. There is no information on population numbers of conservation status and no evidence of seasonality in the region (Best 2007).

Long- and short-finned pilot whales (Globicephala melas and G.macrorhynchus) display a preference for temperate waters and are usually associated with the continental shelf or deep water adjacent to it (Mate et al. 2005; Findlay et al. 1992; Weir 2011). They are regularly seen associated with the shelf edge by MMOs, fisheries observers and researchers operating in Namibian waters (NDP unpubl. data). The distinction between long-finned and short finned (G. macrorhynchus) pilot whales is difficult to make at sea. Short finned pilot whales are regarded as a more tropical species (Best 2007), and most sightings within the Benguela Ecosystem are thought to be long-finned pilot whales, however, due to the low latitude and offshore nature of the survey, it is likely that either could be encountered.

Dusky dolphins (Lagenorhynchus obscurus) (Figure 19, left) are likely to be the most frequently encountered small cetacean in water less than 500 m deep, although their distribution this far north in their range is not well known. The species is very boat friendly and will often approach boats to bowride. This species is resident year round throughout the Benguela ecosystem in waters from the coast to at least 500 m deep (Findlay et al. 1992).



Although no information is available on the size of the population, they are regularly encountered in near shore waters off South Africa and Lüderitz, although encounters near-shore are rare along the central Namibian coast (Walvis Bay area), with most records coming from beyond 5 nautical miles from the coast (Elwen et al. 2010a; NDP unpubl. data). In a recent survey of the Namibian Islands Marine Protected Area (between latitudes of 24˚29’ S and 27˚57’ S and depths of 30-200 m) dusky dolphin were the most commonly detected cetacean species with group sizes ranging from 1 to 70 individuals (NDP unpubl. data), although group sizes up to 800 have been reported in southern African waters (Findlay et al. 1992).

Figure 19: The dusky dolphin Lagenorhynchus obscurus (left) and endemic Heaviside’s dolphin

Cephalorhynchus heavisidii (right) (Photos: www.NamibianDolphinProject.com)).

Heaviside’s dolphins (Figure 19, right) are relatively abundant in both the southern and

northern Benguela ecosystem within the region of 10,000 animals estimated to live in the 400 km of coast between Cape Town and Lamberts Bay (Elwen et al. 2009a) and several hundred animals living in the areas around Walvis Bay and Lüderitz. This species occupies waters from the coast to at least 200 m depth (Elwen et al. 2006; Best 2007), and may show a diurnal onshore-offshore movement pattern, although this varies throughout the range. The survey is likely to be predominantly offshore of the known species range and encounters are unlikely.

The common dolphin (Delphinus spp.) is known to occur offshore in Namibian waters (Findlay et al. 1992). A recent stranding in Lüderitz (May 2012, NDP unpublished data) and MMO reports have confirmed their occurrence in the region. The extent to which they occur in the proposed survey area is currently unknown. Although group sizes can be large, averaging 267 (± SD 287) for the southern African region (Findlay et al. 1992), average sizes of 37 (± SD 31) have been reported for the Namibian region (NDP unpublished data). They are more frequently seen in the warmer waters offshore and to the north of the country, seasonality and encounter rate in the survey area is not known.

Common bottlenose dolphins (Tursiops truncatus) are widely distributed in tropical and temperate waters throughout the world, but frequently occur in small (10s to low 100s) isolated coastal populations. Within Nambian waters two populations of bottlenose dolphins occur. A small population inhabits the very near shore coastal waters (mostly <15m deep) of the central Namibian coastline from approximately Lüderitz in the south to at least Cape Cross in the north. Although the population is thought to number less than 100 individuals (Elwen et al. 2011), its nearshore habitat makes it unlikely to be impacted by the current seismic survey.



An offshore 'form' of common bottlenose dolphis occurs around the coast of southern Africa including Namibia and Angola (Best 2007) with sightings restricted to the continental shelf edge and deeper. Offshore bottlenose dolphins frequently form mixed species groups, often with pilot whales or Risso's dolphins.

Several other species of toothed whales that might occur in the deeper waters of impact area at low levels include the pygmy killer whale, Risso’s, Striped and Right Whale dolphins, and Cuvier’s and Layard’s beaked whales (Findlay et al. 1992; Best 2007). Nothing is known about the population size or density of these species in the survey area but it is likely that encounters would be rare (Findlay et al. 1992; Best 2007).

In summary, there is very little current data on the presence, density or conservation status of any cetaceans within the planned survey area. All information provided above is based on at least some level of projection of information from studies elsewhere in the region, at some time in the past (often decades ago) or extrapolated from knowledge of habitat choice of the species. The large whale species for which there are current data available are the humpback and southern right whale, although with almost all data being limited to the continental shelf. Both these species are known to use feeding grounds around Cape Columbine in South Africa, with numbers there highest between September and February, and not during winter as is common on the South Coast breeding grounds. Whaling data indicates that several other large whale species are also most abundant on the West Coast during this period: fin whales peak in May-July and October-November; sei whale numbers peak in May-June and again in August-October and offshore Bryde’s whale numbers are likely to be highest in January-March. Whale numbers on the shelf and in offshore waters are thus likely to be highest between October and February.

Of the migratory cetaceans, the Blue, Sei and Fin whales are listed as “Endangered” in the IUCN Red Data book. All whales and dolphins are given protection under the South African Law. The Marine Living Resources Act, 1998 (No. 18 of 1998) states that no whales or dolphins may be harassed, killed or fished. No vessel or aircraft may approach closer than 300 m to any whale and a vessel should move to a minimum distance of 300 m from any whales if a whale surfaces closer than 300 m from a vessel or aircraft.

The Cape fur seal (Arctocephalus pusillus pusillus) (Figure 20) is the only species of seal

resident along the west coast of Africa, occurring at numerous breeding and non-breeding sites on the mainland and on nearshore islands and reefs (see Figure 22). Vagrant records from four other species of seal more usually associated with the subantarctic environment have also been recorded: southern elephant seal (Mirounga leoninas), subantarctic fur seal (Arctocephalus tropicalis), crabeater (Lobodon carcinophagus) and leopard seals (Hydrurga leptonyx) (David 1989).

Currently, half the Namibian seal population occurs in southern Namibia, south of Lüderitz. It consists of about 300,000 seals, producing roughly 100,000 pups per year. Atlas Bay, Wolf Bay and Long Islands (near Lüderitz) together represent the largest breeding concentration (about 68,000 pups) of seals in Namibia. Population estimates fluctuate widely between years in terms of pup production, particularly since the mid-1990s (MFMR unpubl. Data; Kirkman et al. 2007). These southern Namibian colonies have important conservation value since they are largely undisturbed at present, as public access to the southern Namibian coast is restricted.



The further large breeding site is at Cape Cross north of Walvis Bay where about 51,000 pups are born annually (MFMR unpubl. Data). The colony supports an estimated 157,000 adults (Hampton 2003), with unpublished data from Marine and Coastal Management (MCM, South Africa) suggesting a number of 187,000 (Mecenero et al. 2006). A further colony of ~9,600 individuals exists on Hollamsbird Island south of Sandwich Harbour. There are also seal colonies at Cape Frio and Möwe Bay, which are located approximately 60 km and 200 km south of the proposed survey area, respectively. The colony at Pelican Point is primarily a haul-out site. The mainland seal colonies present a focal point of carnivore and scavenger activity in the area, as jackals and hyena are drawn to this important food source.

The Cape fur seal population in the Benguela is regularly monitored by the South African and Namibian governments (e.g. Kirkman et al. 2012). Surveys of the full species range done every three years providing data on seal pup production (which can be translated to adult population size), thereby allowing for the generation of high quality data on the population dynamics of this species. The population is considered to be healthy and stable in size although there has been a northward shift in the distribution of the breeding population (Kirkman et al. 2012).

Seals are highly mobile animals with a general foraging area covering the continental shelf up to 120 nautical miles (~220 km) offshore (Shaughnessy 1979), with bulls ranging further out to sea than females. The timing of the annual breeding cycle is very regular occurring between November and January. Breeding success is highly dependent on the local abundance of food, territorial bulls and lactating females being most vulnerable to local fluctuations as they feed in the vicinity of the colonies prior to and after the pupping season (Oosthuizen 1991).

There is a controlled annual quota, determined by government policy, for the harvesting of Cape fur seals on the Namibian coastline. The Total Allowable Catch (TAC) currently stands at 60,000 pups and 5,000 bulls, distributed among four licence holders. The seals are exploited mainly for their pelts (pups), blubber and genitalia (bulls). The pups are clubbed and the adults shot. These harvesting practices have raised concern among environmental and animal welfare organisations (Molloy & Reinikainen 2003). Figure 20: Colony of Cape fur seals Arctocephalus pusillus pusillus (Photo: Dirk Heinrich).



3.4. Other Uses of the proposed Survey Areas

3.4.1 Beneficial Uses

The proposed survey area is located well offshore at depths beyond 150 m. Other users of the area include the commercial fishing industry (see Specialist Report on Fisheries), oil and gas licence holders and and marine mining (diamonds and marine phosphates) concession holders (Figure 21). Recreational use of the coastline and inshore areas is negligible and restricted primarily to the area around Henties Bay, Swakopmund, Walvis Bay and Lüderitz, all of which lie well south of the proposed survey area. Recreational activities offshore of the Namib-Naukluft and the Skeleton Coast National Park are similarly limited.

Figure 21: Project - environment interaction points on the Namibian coast, illustrating the proposed

3D target area in relation to marine diamond mining concessions and other users of the

marine environment.



The main shipping lanes off Namibia lie seawards of the proposed survey areas, however, both coastal shipping and fishing craft may be encountered in the survey area, particularly.

The proposed survey area overlaps with a number of offshore Exclusive Prospecting Licences (EPLs) and Mining Licences. Current activities in the EPLs is minimal to non-existent, the only active operations being diamond mining south of Lüderitz.

Other current and proposed industrial uses of the marine environment include the intake of cooling water for power plants, intake of feed-water for desalination plants, and seawater intakes for fish processing, or mariculture operations. There is also limited guano harvesting on the guano platforms and salt production in Walvis Bay, Swakopmund and at Cape Cross. These activities are all located well to the south of the proposed suervy area and should in no way be affected by seismic survey activities offshore and to the north.

Mariculture activities are being conducted at an increasing scale in Walvis Bay, and at present there are over 20 companies engaged in cultivation of Pacific oyster (Crassostrea gigas) and European flat oyster (Ostrea edulis) in the bay. Oyster cultivation is also conducted in the feed-water ponds of the Walvis Bay and Swakopmund salt works. These various mariculture activities should likewise not be affected in any way by proposed offshore seismic activities.

3.4.2 Conservation Areas and Marine Protected Areas

Numerous conservation areas and a marine protected area (MPA) exist along the coastline and within the project area, although these are all located inshore and to the south of the proposed 3D seismic survey area (Figure 22). They are briefly summarised below.

The Skeleton Coast National Park extends 500 km from the Ugab River in the south to the Kunene River in the north, covering a total land-area of approximately 16,400 km2. The coastline is characterised by many shipwrecks, dense coastal fogs and cold onshore winds. The general public has access only to the southern section between the Ugab and Hoanib rivers, staying at Terrace Bay and Torra Bay. Although open all year to linefish boats, Torra Bay and Terrace Bay are partly closed or restricted to rock- and surf-anglers. There is a seal colony at Cape Frio. The northern section of the Skeleton Coast Park is a tourism concession area and restricted to fly-in safaris only. The park is managed as a wilderness area by the Ministry of Environment and Tourism (MET) due to its ecological sensitivity.

The Dorob National Park, formerly the National West Coast Tourist Recreation Area, was gazetted as a national park under the Nature Conservation Ordinance No. 4 of 1975 in December 2010. The park extends along 1,600 km of coastline between the Kuiseb Delta and the Ugab River, and together with Namib-Naukluft Park covers an area of 107,540 km2. While tourism, sports and recreational activities are allowed in non sensitive areas, the remainder of the park has been divided into zones, which include Damara tern breeding sites, gravel plains, important birds areas, the Kuiseb Delta, Sandwich Harbour, Swakop River, Tsumas Delta, Walvis Bay Lagoon, birding areas and lichen fields.

The Cape Cross Seal Reserve, which is located within the Dorob National Park, is situated approximately 130 km north of Swakopmund. With a surrounding area of 60 km2, the Cape Cross Seal Reserve was proclaimed in 1968 to protect the largest of the 23 breeding colonies of Cape fur seals along the southern African West Coast. Emergent offshore reefs, which serve as seabird nesting areas, are also protected.

Sandwich Harbour, located 55 km south of Walvis Bay, is one of Namibia’s four proclaimed RAMSAR sites and one of southern Africa’s richest coastal wetlands. The area consists of two distinct parts: a northern, saltmarsh and adjoining intertidal sand flat area, which supports



typical emergent vegetation, and a southern area of mudflats and raised shingle bars under tidal influence. The area supports an extremely rich avifauna including eight endangered species among the large numbers of waders, terns, pelicans and flamingos. Bird numbers are reported to reach 175,000, with Palearctic waders reaching densities of 7,000 birds per km2. Several archaeological sites dating back 1000 years also exist within the area (Barnard 1998).

Walvis Bay lagoon is the largest single area of shallow sheltered water along the Namibian coastline. The tidal inlet consists of adjacent intertidal areas, Pelican Point, mudflats exposed at low tide, and sandbars serving as roosting and feeding sites for resident and migratory birds. The wetland consists of natural areas of the lagoon and the Walvis Bay saltworks (Barnard 1998). The site supports up to 250,000 individuals of wetland birds, some species such as flamingos occurring in impressive numbers. Eleven endangered bird species are regularly observed (http://www.ramsar.org/ profile/ profiles_namibia. htm).

Figure 22: Project - environment interaction points on the Namibian coast, illustrating the proposed

3D target area in relation to seabird and seal colonies, conservation areas and marine

protected areas (MPAs).



4. ACOUSTIC IMPACTS OF SEISMIC SURVEYS ON MARINE FAUNA

The ocean is a naturally noisy place and marine animals are continually subjected to both physically produced sounds from sources such as wind, rainfall, breaking waves and natural seismic noise, or biologically produced sounds generated during reproductive displays, territorial defence, feeding, or in echolocation (see references in McCauley 1994). Such acoustic cues are thought to be important to many marine animals in the perception of their environment as well as for navigation purposes, predator avoidance, and in mediating social and reproductive behaviour. Anthropogenic sound sources in the ocean can thus be expected to interfere directly or indirectly with such activities thereby affecting the physiology and behaviour of marine organisms (NRC 2003). Of all human-generated sound sources, the most persistent in the ocean is the noise of shipping. Depending on size and speed, the sound levels radiating from vessels range from 160 to 220 dB re 1 µPa at 1 m (NRC 2003). Especially at low frequencies between 5 to 100 Hz, vessel traffic is a major contributor to noise in the world’s oceans, and under the right conditions, these sounds can propagate 100s of kilometres thereby affecting very large geographic areas (Coley 1994, 1995; NRC 2003; Pidcock et al. 2003).

Seismic surveys are another source of anthropogenic noise. The air-guns used in modern seismic surveys produce some of the most intense non-explosive sound sources used by humans in the marine environment (Gordon et al. 2004). However, the transmission and attenuation of seismic sound is probably of equal or greater importance in the assessment of environmental impacts than the produced source levels themselves, as transmission losses and attenuation are very site specific, and are affected by propagation conditions, distance or range, water and receiver depth and bathymetrical aspect with respect to the source array. In water depths of 25 - 50 m airgun arrays are often audible to ranges of 50 -75 km, and with efficient propagation conditions such as experienced on the continental shelf or in deep oceanic water, detection ranges can exceed 100 km and 1,000 km, respectively (Bowles et al. 1991; Richardson et al. 1995; see also references in McCauley 1994). The signal character of seismic shots also changes considerably with propagation effects. Reflective boundaries include the sea surface, the sea floor and boundaries between water masses of different temperatures or salinities, with each of these preferentially scattering or absorbing different frequencies of the source signal. This results in the received signal having a different spectral makeup from the initial source signal. In shallow water (<50 m) at ranges exceeding 4 km from the source, signals tend to increase in length from <30 milliseconds, with a frequency peak between 10-100 Hz and a short rise time, to a longer signal of 0.25-0.75 seconds, with a downward frequency sweep of between 200 - 500 Hz and a longer rise time (McCauley 1994; McCauley et al. 2000).

In contrast, in deep water received levels vary widely with range and depth of the exposed animals, and exposure levels cannot be adequately estimated using simple geometric spreading laws (Madsen et al. 2006). These authors found that the received levels fell to a minimum between 5 - 9 km from the source and then started increasing again at ranges between 9 – 13 km, so that absolute received levels were as high at 12 km as they were at 2 km, with the complex sound reception fields arising from multi-path sound transmission.

Acoustic pressure variation is usually considered the major physical stimulus in animal hearing, but certain taxa are capable of detecting either or both the pressure and particle velocity components of a sound (Turl 1993). An important component of hearing is the ability to detect sounds over and above the ambient background noise. Auditory masking of a sound occurs when its’ received level is at a similar level to background noise within the same



frequencies. The signal to noise ratio required to detect a pure tone signal in the presence of background noise is referred to as the critical ratio.

The auditory thresholds of many species are affected by the ratio of the sound stimulus duration to the total time (duty cycle) of impulsive sounds of <200 millisecond duration. The lower the duty cycle the higher the hearing threshold usually is. Although seismic sound impulses are extremely short and have a low duty cycle at the source, received levels may be longer due to the transmission and attenuation of the sound (as discussed above).

Below follows a brief review of the impacts of seismic surveys on marine faunal communities. This information is largely drawn from McCauley (1994), McCauley et al. (2000), the Generic EMPR for Oil and Gas Prospecting off the Coast of South Africa (CCA & CMS 2001) and the very comprehensive reviews by Cetus Projects (2007, 2008), compiled as part of the EIA for the Ibhubesi Gas Field and the CGG Veritas surveys on the Namibian shelf, respectively. Although the discussion and assessments focus primarily on marine mammals and turtles, the effects on pelagic and benthic invertebrates, fish and seabirds are also covered.

4.1. Impacts on Plankton

As the movement of phytoplankton and zooplankton is largely limited by currents, they are not able to actively avoid the seismic vessel and thus are likely to come into close contact with the sound sources. Phytoplankton are not known to be affected by seismic surveys and are unlikely to show any significant effects of exposure to air-gun impulses outside of a 1 m distance (Kosheleva 1992; McCauley 1994).

Zooplankton comprises meroplankton (organisms which spend a portion of their life cycle as plankton, such as fish and invertebrate larvae and eggs) and holoplankton (organisms that remain planktonic for their entire life cycle, such as siphonophores, nudibranchs and barnacles). The abundance and spatial distribution of zooplankton is highly variable and dependent on factors such as fecundity, seasonality in production, tolerances to temperature, length of time spent in the water column, hydrodynamic processes and natural mortality. Zooplankton densities are generally low and patchily distributed. The amount of exposure to the influence of seismic airgun arrays is thus dependent on a wide range of variables. Invertebrate members of the plankton that have a gas-filled flotation aid, may be more receptive to the sounds produced by seismic airgun arrays, and the range of effects may extend further for these species than for other plankton. However, for a large seismic array, a pathological effect out to 10 m from the array is considered a generous value with known effects demonstrated to 5 m only (Kostyuchenko 1971).

McCauley (1994) concludes that when compared with total population sizes or natural mortality rates of planktonic organisms, the relative influence of seismic sound sources on these populations can be considered insignificant. The wash from ships propellers and bow waves can be expected to have a similar, if not greater, volumetric effect on plankton than the sounds generated by airgun arrays.

Due to their importance in commercial fisheries, numerous studies have been undertaken experimentally exposing the eggs and larvae of various ichthyoplankton species to airgun sources (reviewed in McCauley 1994). These are discussed further in Section 4.3.



4.2. Impacts on Marine Invertebrates

Many marine invertebrates have tactile organs or hairs (termed mechanoreceptors), which are sensitive to hydro-acoustic near-field disturbances, and some have highly sophisticated statocysts, which have some resemblance to the ears of fishes (Offutt 1970; Hawkins & Myrberg 1983; Budelmann 1988, 1992; Packard et al. 1990; Popper et al. 2001) and are thought to be sensitive to the particle acceleration component of a sound wave in the far-field. However, information on hearing by invertebrates, and noise impacts on them is sparse. Although many invertebrates cannot sense the pressure of a sound wave or the lower amplitude component of high frequency sounds, low frequency high amplitude sounds may be detected via the mechanoreceptors, particularly in the near-field of such sound sources (McCauley 1994). Sensitivity to near-field low-frequency sounds or hydroacoustic disturbances has been recorded for the lobster Homarus americanus (Offut 1970), cephalopods (Hanlon & Budelman 1987; Packard et al. 1990; McCauley et al. 2000) and various other invertebrate species (Horridge 1965, 1966; Horridge & Boulton 1967; Moore & Cobb 1986; Turnpenney & Nedwell 1994).

Despite no quantitative records of invertebrate mortality from seismic sound exposure under field operating conditions, lethal and sub-lethal effects have been observed under experimental conditions where invertebrates were exposed to airguns up to five metres away. These include reduced growth and reproduction rates and behavioural changes in crustaceans (DFO 2004; McCauley 1994; McCauley et al. 2000). The effects of seismic survey energy on snow crab (Chionoecetes opilo) on the Atlantic coast of Canada, for example ranged from no physiological damage but effects on developing fertilized eggs at 2 m range (Christian et al. 2003) to possible bruising of the heptopancreas and ovaries, delayed embryo development, smaller larvae, and indications of greater leg loss but no acute or longer term mortality and no changes in embryo survival or post hatch larval mobility (DFO 2004). The ecological significance of sub-lethal or physiological effects could thus range from trivial to important depending on their nature.

Behavioural responses of invertebrates to particle motion of low frequency stimulation has been measured by numerous researchers (reviewed in McCauley 1994). Again a wide range of responses are reported ranging from no avoidance by free ranging invertebrates (crustaceans, echinoderms and molluscs) of reef areas subjected to pneumatic airgun fire (Wardle et al. 2001), and no reduction in catch rates of brown shrimp (Webb & Kempf 1998), prawns (Steffe & Murphy 1992, in McCauley, 1994) or rock lobsters (Parry & Gasson 2006) in the near-field during or after seismic surveys.

Cephalopods, in contrast, may be receptive to the far-field sounds of seismic airguns. Recent electrophysiological studies have confirmed that cephalopods show sensitivity to frequencies under 400 Hz (Octopus vulgaris, Kaifu et al. 2008; Sepioteuthis lessoniana, Octopus vulgaris, Hu et al. 2009; Loligo pealei, Mooney et al. 2010). Behavioural response range from attraction at 600 Hz pure tone (Maniwa 1976), through startle responses at received levels of 174 dB re 1 µPa, to increase levels of alarm responses once levels had reached 156 – 161 dB re 1 µPa (McCauley et al. 2000). Based on the results of caged experiments, McCauley et al. (2000) suggested that squid would significantly alter their behaviour at an estimated 2 - 5 km from an approaching large seismic source. More recently, Andre et al. (2011) demonstrated that received sound levels of 175 dB re 1 µPa resulted in severe acoustic trauma (morphological damage to the statoscysts and afferent dendrites) in four cephalopod species tested under controlled-exposure experiments. Giant squid strandings coincident with seismic surveys have been reported (Guerra et al. 2004). Although animals showed no external damage, all had



severe internal injuries (including disintegrated muscles and unrecognisable organs) indicative of having ascended from depth too quickly. The causative link to seismic surveys has, however, not been established with certainty.

4.3. Impacts on Fish

Fish hearing has been reviewed by numerous authors including Popper and Fay (1973), Hawkins (1973), Tavolga et al. (1981), Lewis (1983), Atema et al. (1988), and Fay (1988). Fish have two different systems to detect sounds namely 1) the ear (and the otolith organ of their inner ear) that is sensitive to sound pressure and 2) the lateral line organ that is sensitive to particle motion. Certain species utilise separate inner ear and lateral line mechanisms for detecting sound; each system having its own hearing threshold (Tavolga & Wodinsky 1963), and it has been suggested that fish can shift from particle velocity sensitivity to pressure sensitivity as frequency increases (Cahn et al. 1970, in Turl 1993).

In fish, the proximity of the swim-bladder to the inner ear is an important component in the hearing as it acts as the pressure receiver and vibrates in phase with the sound wave. Vibrations of the otoliths, however, result from both the particle velocity component of the sound as well as stimulus from the swim-bladder. The resonant frequency of the swim-bladder is important in the assessment of impacts of sounds as species with swim-bladders of a resonant frequency similar to the sound frequency would be expected to be most susceptible to injury. Although the higher frequency energy of received seismic impulses needs to be taken into consideration, the low frequency sounds of seismic surveys would be most damaging to swim-bladders of larger fish. The lateral line is sensitive to low frequency (between 20 and 500 Hz) stimuli through the particle velocity component of sound.

Most species of fish and elasmobranchs are able to detect sounds from well below 50 Hz (some as low as 10 or 15 Hz) to upward of 500 – 1 000 Hz (Popper & Fay 1999; Popper 2003; Popper et al. 2003), and consequently can detect sounds within the frequency range of most widely occurring anthropogenic noises (Vasconcelos et al. 2007; Codarin et al. 2009). Within the frequency range of 100 – 1 000 Hz at which most fish hear best, hearing thresholds vary considerably (50 and 110 dB re 1 µPa). They are able to discriminate between sounds, determine the direction of a sound, and detect biologically relevant sounds in the presence of noise. In addition, some clupeid fish can detect ultrasonic sounds to over 200 kHz (Popper & Fay 1999; Mann et al. 2001; Popper et al. 2004). Fish that possess a coupling between the ear and swim-bladder have probably the best hearing of fish species (McCauley 1994). Consequently, there is a wide range of susceptibility among fish to seismic sounds, with those with a swim-bladder will be more susceptible to anthropogenic sounds than those without this organ.

Studies have shown that fish can be exposed directly to the sound of seismic survey without lethal effects, outside of a very localised range of physiological effects. Physiological effects of impulsive airgun sounds on fish species include swim-bladder damage (Falk & Lawrence 1973), transient stunning (Hastings 1990, in Turnpenney & Nedwell 1994), short-term biochemical variations in different tissues typical of primary and secondary stress response (Santulli et al. 1999; Smith et al. 2004; Buscaino et al. 2010), and temporary hearing loss due to destruction of the hair cells in the hearing maculae (Enger 1981; Lombarte et al. 1993; Hastings et al. 1996; McCauley et al. 2000; Scholik & Yan 2001, 2002; McCauley et al. 2003; Popper et al. 2005; Smith et al. 2006). Popper (2008) concludes that as the vast majority of



fish exposed to seismic sounds will in all likelihood be some distance from the source, where the sound level has attenuated considerably, only a very small number of animals in a large population will ever be directly killed or damaged by sounds from seismic airgun arrays.

Behavioural responses to impulsive sounds are varied and include leaving the area of the noise source (Suzuki et al. 1980; Dalen & Rakness 1985; Dalen & Knutsen 1987; Løkkeborg 1991; Skalski et al. 1992; Løkkeborg & Soldal 1993; Engås et al. 1996; Wardle et al. 2001; Engås & Løkkeborg 2002; Hassel et al. 2004), changes in depth distribution (Chapman & Hawkins 1969; Dalen 1973; Pearson et al. 1992; Slotte et al. 2004), spatial changes in schooling behaviour (Slotte et al. 2004), and startle response to short range start up or high level sounds (Pearson et al. 1992; Wardle et al. 2001). In some cases behavioural responses were observed at up to 5 km distance from the firing airgun array (Santulli et al. 1999; Hassel et al. 2004). Behavioural effects are generally short-term, however, with duration of the effect being less than or equal to the duration of exposure, although these vary between species and individuals, and are dependent on the properties of the received sound. In some cases behaviour patterns returned to normal within minutes of commencement of surveying indicating habituation to the noise. Disturbance of fish is believed to cease at noise levels below 160 dB re 1µPa. The ecological significance of such effects is therefore expected to be low, except in cases where they influence reproductive activity.

There are currently concerns that seismic survey activities in southern Namibia are linked to reductions in tuna catches (David Russel, pers. comm.). The respective Ministries have however, agreed that additional research is needed on the subject before policy decisions on seismics and fisheries can be made (G. Schneider, Geological Survey of Namibia (GSN), pers. comm.).

Although the effects of airgun noise on spawning behaviour of fish have not been quantified to date, it is predicted that if fish are exposed to powerful external forces on their migration paths or spawning grounds, they may be disturbed or even cease spawning altogether. The deflection from migration paths may be sufficient to disperse spawning aggregations and displace spawning geographically and temporally, thereby affecting recruitment to fish stocks. The magnitude of effect in these cases will depend on the biology of the species and the extent of the dispersion or deflection. Dalen et al. (1996), however, recommended that in areas with concentrated spawning or spawning migration seismic shooting be avoided at a distance of ~50 km from these areas.

Indirect effects of seismic shooting on fish include reduced catches resulting from changes in feeding behaviour or vertical distribution (Skalski et al. 1992), but information on feeding success of fish (or larger predators) in association with seismic survey noise is lacking.

The physiological effects of seismic sounds from airgun arrays will mainly affect the younger life stages of fish such as eggs, larvae and fry, many of which form a component of the meroplankton and thus have limited ability to escape from their original areas in the event of various influences. Numerous studies have been undertaken experimentally exposing the eggs and larvae of various fish species to airgun sources (Kostyuchenko 1971; Dalen & Knutsen 1987; Holliday et al. 1987; Booman et al. 1992; Kosheleva 1992; Popper et al. 2005, amongst others). These studies generally identified mortalities and physiological injuries at very close range (<5 m) only. For example, increased mortality rates for fish eggs were proven out to ~5 m distance from the airguns. A mortality rate of 40-50% was recorded for yolk sac larvae (particularly for turbot) at a distance of 2-3 m (Booman et al. 1996), although mortality figures for yolk sac larvae of anchovies at the same distances were lower (Holliday et al. 1987). Yolk



sac larvae of cod experienced significant eye injuries (retinal stratification) at a distance of 1 m from an airgun array (Matishov 1992), and Booman et al. (1996) report damage to brain cells and lateral line organs at <2 m distance from an airgun array. Increased mortality rates (10-20%) at later stages (larvae, post-larvae and fry) were proven for several species at distances of 1-2 m. Changes have also been observed in the buoyancy of the organisms, in their ability to avoid predators and effects that affect the general condition of larvae, their growth rate and thus their ability to survive. Temporary disorientation juvenile fry was recorded for some species (McCauley 1994). Fish larvae with swim-bladders may be more receptive to the sounds produced by seismic airgun arrays, and the range of effects may extend further for these species than for others.

From a fish resource perspective, these effects may potentially contribute to a certain diminished net production in fish populations. However, Sætre & Ona (1996) calculated that under the "worst case" scenario, the number of larvae killed during a typical seismic survey was 0.45% of the total larvae population. When more realistic "expected values" were applied to each parameter of the calculation model, the estimated value for killed larvae during one run was equal to 0.03% of the larvae population. If the same larval population was exposed to multiple seismic runs, the effect would add up for each run. For species such as cod, herring and capelin, the natural mortality is estimated at 5-15% per day of the total population for eggs and larvae. This declines to 1-3% per day once the species reach the 0 group stage i.e. at approximately 6 months (Sætre & Ona 1996). Consequently, Dalen et al. (1996) concluded that seismic-created mortality is so low that it can be considered to have an inconsequential impact on recruitment to the populations.

4.4. Impacts on Seabirds

Among the marine avifauna in southern African waters, it is only the diving birds, or birds which rest on the water surface, that may be affected by the underwater noise of seismic surveys. The African penguin (Spheniscus demersus), which is flightless and occurs along the West Coast, would be particularly susceptible to impacts from underwater seismic noise. In African penguins the best hearing is in the 600 Hz to 4 kHz range with the upper limit of hearing at 15 kHz and the lower limit at 100 Hz (Wever et al. 1969). No critical ratios have, however, been measured. Principal energy of vocalisation of African penguins was found at <2 kHz, although some energy was measured at up to 6 kHz (Wever et al. 1969).

The continuous nature of the intermittent seismic survey pulses, however, suggest that birds would hear the sound sources at distances where levels would not induce mortality or injury, and consequently be able to flee an approaching sound source. Consequently, the potential for injury to seabirds from seismic surveys in the open ocean is deemed to be low (see also Stemp 1985, in Turnpenny & Nedwell 1994; Lacroix et al. 2003), particularly given the extensive feeding range of the plunge-diving seabird species.

4.5. Impacts on Turtles

The potential effects of seismic surveys on turtles include:

• Physiological injury (including disorientation) or mortality from seismic noise; • Behavioural avoidance of seismic survey areas; • Collision with or entanglement in towed seismic apparatus;



• Masking of environmental sounds and communication; • Indirect effects due to effects on prey.

Available data on marine turtle hearing is limited, but suggest highest auditory sensitivity

at frequencies of 250 – 700 Hz, and some sensitivity to frequencies at least as low as 60 Hz (Ridgway et al. 1969; Wever et al. 1978, in McCauley 1994; O’Hara & Wilcox, 1990; Moein-Bartol et al. 1999). The overlap of this hearing sensitivity with the higher frequencies produced by airguns, suggest that turtles may be considerably affected by seismic noise.

No information on physiological injury to turtle hearing could be sourced in the literature. If subjected to seismic sounds at close range, temporary or permanent hearing impairment may result, but it is unlikely to cause death or life-threatening injury. As with other large mobile marine vertebrates, it is assumed that sea turtles will avoid seismic noise at levels/distances where the noise is a discomfort. Juvenile turtles may be unable to avoid seismic sounds in the open ocean, and consequently may be more susceptible to seismic noise.

Behavioural changes in response to anthropogenic sounds have been reported for some sea turtles. Controlled exposure experiments on captive turtles found an increase in swim speed and erratic behaviour indicative of avoidance, at received airgun sound levels of 166 – 176 dB re 1 µPa (O’Hara & Wilcox 1990; McCauley et al. 2000). Sounds of frequency of 250 and 500 Hz resulted in a startle response from a loggerhead turtle (Lenhardt et al. 1983, in McCauley 1994), and avoidance by 30 m of operating airguns where the received level would have been in the order of 175 - 176 dB re 1 µPa (O’Hara 1990). McCauley (1994), however, pointed out that these results may have been influenced by echo associated with the shallow environment in which the test was undertaken.

Further trials carried out on caged loggerhead and green turtles include those of Moein et al. (1994) and McCauley et al. (2000), who investigated responses to airgun impulses by measuring avoidance behaviour, physiological response and electroencephalogram measurements of hearing capability. Results indicated that significant avoidance response occurred at received levels ranging between 172 and 176 dB re 1 µPa at 24 m, and repeated trails several days later suggest either temporary reduction in hearing capability or habituation with repeated exposure. Hearing however returned after two weeks (Moein et al. 1994; McCauley et al. 2000). McCauley et al. (2000) reported that above levels of 166 dB re 1 µPa turtles increased their swimming activity compared to periods when airguns were inactive. Above 175 dB re 1 µPa turtle behaviour became more erratic possibly reflecting an agitated behavioural state at which unrestrained turtles would show avoidance response by fleeing an 4operating sound source. These would correspond to distances of 2 km and 1 km from a seismic vessel operating in 100 - 120 m of water, respectively.

Observations of marine turtles during a ten-month seismic survey in deep water (1,000-3,000 m) off Angola found that turtle sighting rate during guns-off (0.43 turtles/h) was double that of full-array seismic activity (0.20/h) (Weir 2007). In contrast, Parente et al. (2006), working off Brazil found no significant differences in turtle sightings with airgun state. Weir (2007) notes that while her results are suggestive of avoidance of airguns by turtles, they should be treated with caution since a large proportion of the sightings occurred during unusually calm conditions and during peak diurnal abundance of turtles when the airguns were inactive. While there was indication that turtles occurred closer to the source during guns-off than full-array, there was no significant difference in the median distance of turtle sightings from the airguns during full-array or guns-off, suggesting a lack of movement away from active



airguns. It is thus possible that during deep water surveys turtles only detect airguns at close range or are not sufficiently mobile to move away from approaching airgun arrays (particularly if basking for metabolic purposes when they may be slow to react) (Weir 2007). This is in marked contrast to previous assessments that assumed that the impact of seismic noise on behaviour of adult turtles in the open ocean environment is of low significance given the mobility of the animals (CSIR 1998; CCA & CMS 2001). In the study by Weir (2007) a confident assessment of turtle behaviour in relation to seismic status was hindered, however, by the apparent reaction of individual animals to the survey vessel and towed equipment rather than specifically to airgun sound. As these reactions occurred at close range (usually <10 m) to approaching objects, they appeared to be based principally on visual detection (Weir 2007).

Although collisions between turtles and vessels are not limited to seismic ships, the large amount of equipment towed astern of survey vessels does increase the potential for collision, or entrapped within seismic equipment and towed surface floats. Basking turtles are particularly slow to react to approaching objects may not be able to move rapidly away from approaching airguns even if motivated to do so. In the past, almost all reported turtle entrapments have been associated with the tail buoy; the large float attached to the end of each seismic cable, which is used to monitor the location of the cable. The tail buoys have a subsurface structure ('undercarriage') consisting of a 'twin-fin' design, which is primarily used for counter-balancing the upper structure to ensure stability in the water. Towing points are located on the leading edge of each side of the undercarriage, and these are attached by chains to a swivel leading to the end of the seismic cable (Ketos Ecology 2009). It is thought that entrapment occurs either as a result of 'startle diving' in front of towed equipment or following foraging on barnacles and other organisms growing along seismic cables and surfacing to breathe immediately in front of the tail buoy (primarily loggerhead and Olive Ridley turtles). In the first case the turtle becomes stuck within the angled gap between the chains and the underside of the buoy, lying on their sides across the top of the chains and underneath the float with their ventral surface facing the oncoming water thereby causing the turtle to be held firmly in position (Figure 23, left). Depending on the size of the turtle, they can also become stuck within the gap below a tail buoy, which extends to 0.8 m below water level and is ~0.6 m wide. The animal would need to be small enough to enter the gap, but too big to pass all the way through the undercarriage. Furthermore, the presence of the propeller in the undercarriage of some buoy-designs prohibits turtles that have entered the undercarriage from travelling out of the trailing end of the buoy (Figure 23, right). Once stuck inside or in front of a tail buoy, the water pressure generated by the 4–5 kts towing speed, would hold the animal against/inside the buoy with little chance of escape due to the angle of its body in relation to the forward movement of the buoy. For a trapped turtle this situation will be fatal, as it will be unable to reach the surface to breathe (Ketos Ecology 2009). To prevent entrapment, the seismic inductry has implemented the use of “turtle guards” on all tailbuoys.

Breeding adults of sea turtles undertake large migrations between their nesting sites and distant foraging areas. Although Lenhardt et al. (1983) speculated that turtles may use acoustic cues for navigation during migrations, information on turtle communication is lacking. The effect of seismic noise in masking environmental cues such as surf noise (150-500 Hz), which overlaps the frequencies of optimal hearing in turtles (McCauley 1994), is unknown and speculative.



Figure 23: Turtles commonly become trapped in front of the undercarriage of the tail buoy in the

area between the buoy and the towing chains (left), and inside the 'twin-fin'

undercarriage structure (right) (Ketos Ecology 2009).

4.6. Impacts on Seals

The Cape fur seal forages over the continental shelf to depths of over 200 m and would consequently be expected to occur within the proposed seismic survey area.

Underwater behavioural audiograms have been obtained for two species of Otariidae (sea lions and fur seals), but no audiograms have been measured for Cape fur seals. Extrapolation of these audiograms to below 100 Hz would result in hearing thresholds of approximately 140-150 dB re 1 µPa for the California sea lion and well above 150 dB re 1 µPa for the Northern fur seal. The range of greatest sensitivity in fur seals lies between the frequencies of 2-32 kHz (McCauley 1994). Underwater critical ratios have been measured for two northern fur seals and averaged ranged from 19 dB at 4 kHz to 27 dB at 32 kHz. The audiograms available for otariid pinnipeds suggest they are less sensitive to low frequency sounds (<1 kHz) than to higher frequency sounds (>1 kHz). The range of low frequency sounds (30-100 Hz) typical of seismic airgun arrays thus falls below the range of greatest hearing sensitivity in fur seals. This generalisation should, however, be treated with caution as no critical ratios have been measured for Cape fur seals.

Seals produce underwater sounds over a wide frequency range, including low frequency components. Although no measurement of the underwater sounds have been made for the Cape fur seal, such measurements have been made for a con-generic species Arctocephalus philippii, which produced narrow-band underwater calls at 150 Hz. Aerial calls of seals range up to 6 Hz, with the dominant energy in the 2-4 kHz band. However, these calls have strong tonal components below 1 kHz, suggesting some low frequency hearing capability and therefore some susceptibility to disturbance from the higher frequency components of seismic airgun sources (Goold & Fish 1998; Madsen et al. 2006).

The potential impact of seismic survey noise on seals could include physiological injury to individuals, behavioural avoidance of individuals (and subsequent displacement from key habitat), masking of important environmental or biological sounds and indirect effects due to effects on predators or prey.

The physiological effects of loud low frequency sounds on seals are not well documented, but include cochlear lesions following rapid rise time explosive blasts (Bohne et al. 1985; 1986,



in McCauley 1994), temporary threshold shifts (TTS) following exposure to octave-band noise (frequencies ranged from 100 Hz to 2000 Hz, octave-band exposure levels were approximately 60–75 dB, while noise-exposure periods lasted a total of 20–22 min) (Kastak et al. 1999), with recovery to baseline threshold levels within 24 h of noise exposure. Proposed injury criteria for seals exposed to noise events within a 24-h period are provided in (Table 6).

Using measured discomfort and injury thresholds for humans, Greenlaw (1987) modelled the pain threshold for seals and sea lions and speculated that this pain threshold was in the region of 185 – 200 dB re 1 µPa. The impact of physiological injury to seals from seismic noise is deemed to be low as it is assumed that highly mobile creatures such as fur seals would avoid severe sound sources at levels below those at which discomfort occurs. However, noise of moderate intensity and duration may be sufficient to induce TTS under water in pinniped species (Kastak et al. 1999). Reports of seals swimming within close proximity of firing airguns should thus be interpreted with caution in terms of the impacts on individuals as such individuals may well be experiencing hearing threshold shifts.

Information on the behavioural response of fur seals to seismic exploration noise is lacking (Richardson et al. 1995; Gordon et al. 2004). Reports of studies conducted with Harbour and Grey seals include initial startle reaction to airgun arrays, and range from partial avoidance of the area close to the vessel (within 150 m) (Harris et al. 2001) to fright response (dramatic reduction in heart rate), followed by a clear change in behaviour, with shorter erratic dives, rapid movement away from the noise source and a complete disruption of foraging behaviour (Gordon et al. 2004). In most cases, however, individuals quickly reverted back to normal behaviour once the seismic shooting ceased and did not appear to avoid the survey area. Seals seem to show adaptive responses by moving away from airguns and reducing the risk of sustaining hearing damage. Potential for long-term habitat exclusion and foraging disruption over longer periods of exposure (i.e. during full-scale surveys conducted over extended periods) is however a concern.

Cape fur seals generally appear to be relatively tolerant to noise pulses from underwater explosives, which are probably more invasive than the slower rise-time seismic sound pulses. There are also reports of Cape fur seals approaching seismic survey operations and individuals biting hydrophone streamers (CSIR 1998). This may be related to their relative insensitivity to sound below 1 kHz and their tendency to swim at or near the surface, exposing them to reduced sound levels. It has also been suggested that this attraction is a learned response to towed fishing gear being an available food supply.

4.7. Impacts on Whales and Dolphins

The cetaceans comprise baleen whales (mysticetes) and toothed whales and dolphins (odontocetes). The potential impact of seismic survey noise on cetaceans includes a) physiological injury to individuals, b) behavioural disturbance (and subsequent displacement from key habitat), c) masking of important environmental or biological sounds, or d) effects due to indirect effects on prey. Reactions of cetaceans to anthropogenic sounds have been reviewed by McCauley (1994), Richardson et al. (1995), Gordon & Moscrop (1996) and Perry (1998). More recently reviews have focused specifically on the effects of sounds from seismic surveys on marine mammals (DFO 2004; Gordon et al. 2004; NRC 2005; Nowacek et al. 2007; Southall et al. 2007; Abgrall et al. 2008, amongst others).



4.7.1 Cetacean vocalisations

Cetacean are highly reliant on acoustic channels for orientation in their environment, feeding and social communication (Tyack & Clark 2000). Baleen whales produce a wide repertoire of sounds ranging in frequencies from 12 Hz to 8 kHz (Richardson et al. 1995). Vocalisations may be produced throughout the year (Dunlop et al. 2007; Mussoline et al. 2012; Vu et al. 2012), with peaks in call rates during breeding seasons in some species, most notably humpback whales (Winn & Winn 1978).

Odontocetes produce a spectrum of vocalizations including whistles, pulsed sounds and echolocation clicks (Popper 1980). Whistles play a key role in social communication, they are concentrated in the 1-30 kHz frequency range but may extend up to 75 kHz (Samarra et al. 2010) and contain high frequency harmonics (Lammers et al. 2003). The characteristics of burst pulsed sounds are highly variable, concentrated in the mid frequency for killer whales (Richardson et al. 1995), but extending well into the ultrasonic frequency range for other dolphin species (Lammers et al. 2003). Although most odontocete vocalizations are predominantly in mid and high frequency bands, there are recent descriptions of dolphins producing low frequency moans (150-240 Hz) and low frequency modulated tonal calls (990 Hz) (van der Woude, 2009; Simrad et al., 2012), the function of which remains unclear but may be related to social behaviours.

Clicks are high intensity, short sounds associated with orientation and feeding. The frequency composition of echolocation clicks varies with species. Most delphinids produce broad band echolocation clicks with frequencies which extend well up into the ultra-sonic range > 100 kHz (Richardson et al. 1995). Sperm whales produce broadband echolocation clicks reaching up to 40 kHz in frequency (Backus and Schevill, 1966; Madsen et al., 2002). Neonatal sperm whales produce lower frequency sounds at 300-1700 Hz (Madsen et al., 2003). Porpoise, Kogiids and dolphins in the genus Cephalorhynchus (including the Heaviside’s dolphin) produce characteristic narrow band, high frequency (NBHF) echolocation clicks with a central frequency around 125 kHz (Madsen et al., 2005a; Morisaka et al., 2011). Beaked whales produce low frequency sounds (Richardson et al., 1995) and mid frequency echolocation clicks, burst pulse vocalisations and frequency modulated pulses with energy concentrated at 10 kHz and above (Madsen et al., 2005b; Rankin et al., 2011).

4.7.2 Cetacean hearing

Cetacean hearing has received considerable attention in the international literature, and available information has been reviewed by several authors including Popper (1980), Fobes & Smock (1981), Schusterman (1981), Ridgway (1983), Watkins & Wartzok (1985), Johnson (1986), Moore & Schusterman (1987) and Au (1993).

Marine mammals as a group have wide variations in ear anatomy, frequency range and amplitude sensitivity. The hearing threshold is the amplitude necessary for detection of a sound and varies with frequency across the hearing range (Nowacek et al. 2007). Hearing thresholds differ between odontocetes and baleen whales, and between individuals, resulting in different levels of sensitivity to sounds at varying frequencies. For most species, hearing sensitivity corresponds closely to the frequencies at which they vocalise, however it is likely that hearing range is broader than vocalisation range (Bradley & Stern 2008).

Behavioural and electrophysical audiograms are available for several species of small- to medium-sized toothed whales (killer whale: Hall & Johnson 1972; Bain et al. 1993, false killer



whale: Thomas et al. 1988, bottlenose dolphins: Johnson 1967, beluga: White et al. 1978; Awbrey et al. 1988, Harbour porpoise: Andersen 1970, Chinese river dolphin: Ding Wang et al. 1992 and Amazon river dolphin: Jacobs & Hall 1972; Risso’s dolphin: Nachtigall et al. 1995, 1996, Harbour porpoise: Lucke et al. 2009). In these species, hearing is centered at frequencies between 10 and 100 kHz (Richardson et al.1995; Table 4). The high hearing thresholds at low frequency for those species tested implies that the low frequency component of seismic shots (10 - 300 Hz) will not be audible to the small to medium odontocetes at any great distance. However, the higher frequency of an airgun array shot, which can extend to 15 kHz and above (Madsen et al. 2006) may be audible from tens of kilometres away, due to the very low sensitivity thresholds of many toothed whales at frequencies exceeding 1 kHz.

No psycho-acoustical or electrophysical work on the sensitivity of baleen whales to sound has been conducted (Richardson et al. 1995) and hypotheses regarding the effects of sound in baleen whales are extrapolations from what is known to affect odontocetes or other marine mammals and from observations of behavioural responses. A partial response “audiogram” exists for the gray whale based on the avoidance of migrating whales to a pure tone source (Dahlheim & Ljungblad 1990). Frankel et al. (1995, in Perry 1998) found humpback whales in the wild to detect sounds ranging from 10 Hz to 10 kHz at levels of 102 to 106 dB re 1 µPa. Blue whales reduce calling in the presence of mid-frequency sonar (1-8 kHz) providing evidence that they are receptive to sound in this range (Melcón et al. 2012). Based on the low frequency calls produced by larger toothed whales, and anatomical and paleaontological evidence for baleen whales, it is predicted that these whales hear best in the low frequencies (Fleischer 1976, 1978; McCauley 1994), with hearing likely to be most acute below 1 kHz (Fleischer 1976, 1978; Norris & Leatherwood 1981; Table 4). The available information demonstrates that the larger toothed whales and baleen whales will be very receptive to the sound produced by seismic airgun arrays and consequently this group may be more affected by this type of disturbance than toothed whales (Nowacek et al. 2007).

4.7.3 Physiological injury and stress

Exposure to high sound levels can result in physiological injury to cetaceans through a number of avenues, including shifts of hearing thresholds (as either permanent (PTS) or temporary threshold shifts (TTS)) (Richardson et al. 1995; Au et al. 1999; Schlundt et al. 2000; Finneran et al. 2000, 2001, 2002, 2003), tissue damage (Lien et al. 1993; Ketten et al. 1993), acoustically induced decompression sickness particularly in beaked whales (Crum & Mao 1996; Cox et al. 2006), and non-auditory physiological effects including elevated blood pressures, increased heart and respiration rates, and temporary increases in blood catecholamines and glucocorticoids (Bowles & Thompson 1996), which may have secondary impacts on reproduction. Most studies conducted on sound-related injuries in cetaceans, however, investigated the effects of explosive pulses (Bohne et al. 1985, 1986; Lien et al. 1993; Ketten et al. 1993) and mid-frequency sonar pulses (Simmonds & Lopez-Jurado 1991; Crum & Mao 1996; Frantzis 1998; Balcomb & Claridge 2001; Evans & England 2001; Jepson et al. 2003; Cox et al. 2006), and the results are thus not directly applicable to non-explosive seismic sources such as those from airgun arrays.

Both PTS and TTS represent actual changes in the ability of an animal to hear, usually at a particular frequency, whereby it is less sensitive at one or more frequencies as a result of exposure to sound (Nowacek et al. 2007). Southall et al. (2007) propose a dual criterion for



assessing injury from noise based on the peak sound pressure level (SPL) and sound exposure level (SEL) (a measure of injury that incorporates the sound pressure level and duration), with the one that is exceeded first used as the operative injury criterion. For a pulsed sound source such as that generated during seismic seabed surveys, the levels for PTS are 230 dB re:1 µPa (peak) and 198 re:1 µPa2-s for SPL and SEL respectively for low, medium and high frequency cetaceans (Table 4). For TTS these values are 224 dB re:1 µPa (peak) and 183 dB re:1 µPa2-s for SPL and SEL, respectively. There is thus a range at which permanent or temporary hearing damage might occur, although some hearing damage may already occur when received levels exceed 183 dB re:1 µPa2-s SEL. Table 4: Functional hearing groups, auditory bandwidth (estimated lower to upper frequency

hearing cut-off) and proposed injury criterion of marine mammals (exposed through either

single or multiple noise events within a 24-h period) found in Namibia (adapted from

Southall et al. 2007).

Functional

hearing group

Estimated

auditory

bandwidth

Marine mammal group

Proposed injury criteria

for pulsed sounds -

a) Sound pressure level

b) Sound exposure level.

Low frequency

cetaceans

7 Hz to 22 kHz All baleen whales

PTS

a) 230 dB re:1µPa (peak)

b) 198 dB re: 1µPa2 - s

TTS


b) 183 dB re: 1 µPa2-s

Mid frequency

cetaceans

150 Hz to 160 kHz Steno, Sotalia, Tursiops,

Stenella, Delphinus,

Lagenorhynchus,

Lissodelphis, Grampus,

Feresa, Pseudorca, Orcinus,

Globicephala, Physeter,

Ziphius, Berardius,

Hyperoodon, Mesoplodon

High frequency

cetaceans

200 Hz to 180 kHz Cephalorhynchus, Kogia,

Pinnepeds

(in water)

75 Hz to 75 kHz Arctocephalus PTS


b) 186 dB re: 1µPa2 - s

TTS


b) 171 dB re: 1 µPa2-s

Based on statistical simulations accounting for uncertainty in the available data and

variability in individual hearing thresholds, Gedamke et al. (2011) conclude that the possibility of seismic activity leading to TTS in baleen whales must be considered at distances up to several kilometers. As cetaceans are highly reliant on sound, hearing damage leading to TTS and PTS is likely to result in a reduction in foraging efficiency, reproductive potential, social cohesion and ability to detect predators (Weilgart 2007).

Overlap between the frequency spectra of seismic shots and the hearing threshold curve with frequency for some toothed whale species, suggests that these may react to seismic shots



at long ranges, but that hearing damage from seismic shots is only likely to occur at close range. They will thus not be affected as severely as many fish, and possibly sea turtles and baleen whales that have their greatest hearing sensitivity at low frequencies (McCauley 1994).

Noise induced stress resulting from exposure to sources of marine sound can cause detrimental changes in blood hormones, including cortisol (Romano et al. 2004). The timing of the stressor relative to seasonal feeding and breeding cycles (such as those observed in migrating baleen whales) may influence the degree of stress induced by noise exposure (Tyack 2008). However, quantifying stress caused by noise in wild populations is difficult as it is not possible to determine the physiological responses of an animal to a noise stressor based on behavioural observations alone (Wright et al. 2007). One recent study was able to identify a reduction in stress-related faecal hormone metabolites (glucocorticoids) in North Atlantic right whales concurrent with a 6 dB reduction in shipping noise. This study provided the first evidence that exposure to low-frequency ship noise may be associated with chronic stress in whales (Rolland et al. 2013).

4.7.4 Behavioural disturbance

The factors that affect the response of marine mammals to sounds in their environment include the sound level and other properties of the sound, the physical and behavioural state of the animal and its prevailing acoustic characteristics, and the ecological features of the environment in which the animal encounters the sound. The responses of cetaceans to noise sources are often also dependent on the perceived motion of the sound source, as well as the nature of the sound itself. For example, many whales are more likely to tolerate a stationary source than they are one that is approaching them (Watkins 1986; Leung-Ng & Leung 2003), or are more likely to respond to a stimulus with a sudden onset than to one that is continuously present (Malme et al. 1985).

The speed of sound increases with increasing temperature, salinity and pressure (Richardson et al. 1995) and stratification in the water column affects the rate of propagation loss of sounds produced by an airgun array. As sound travels, acoustic shadow and convergence zones may be generated as sound is refracted towards areas of slower sound speed. These can lead to areas of high and low noise intensity (shadow zones) so that exposure to different pulse components at distances of 1-13 km from the seismic source does not necessarily lessen (attenuate) with increasing range. In some cases this can lead to received levels at 12 km being as high as those at 2 km (Madsen et al. 2006). Depending on the propagation conditions of the water column, animals may need to move closer to the sound source or apply vertical rather than horizontal displacement to reduce their exposure, thus making overall avoidance of the sound source difficult Although such movement may reduce received levels in the short-term it may prolong the overall exposure time and accumulated sound exposure level (SEL) (Madsen et al. 2006).

Typical behavioural response in cetaceans to seismic airgun noise include initial startle responses (Malme et al. 1985; Ljungblad et al. 1988; McCauley et al. 2000), changes in surfacing behaviour (Ljungblad et al. 1988; Richardson et al. 1985a; McCauley et al. 1996, 2000), shorter dives (Ljungblad et al. 1988), changes in respiration rate (Ljungblad et al. 1988; Richardson et al. 1985, 1986; Malme et al. 1983, 1985,1986), slowing of travel (Malme et al. 1983, 1984), and changes in vocalisations (McDonald et al. 1993, 1995) and call rate (Di Lorio & Clarke 2010). These subtle changes in behavioural measures are often the only observable



reaction of whales to reception of anthropogenic stimuli, and there is no evidence that these changes are biologically significant for the animals (see for example McCauley 1994). Possible exceptions are impacts at individual (through reproductive success) and population level through disruption of feeding within preferred areas (as reported by Weller et al. (2002) for Western gray whales). For continuous noise, whales begin to avoid sounds at exposure levels of 110 dB, and more than 80% of species observed show avoidance to sounds of 130 dB re:1µPa. For seismic noise, most whales show avoidance behaviour above 160 dB re:1µPa (Malme et al. 1983, 1984; Ljungblad et al. 1988; Pidcock et al. 2003). Behavioural responses are often evident beyond 5 km from the sound source (Ljungblad et al. 1988; Richardson et al. 1986, 1995), with the most marked avoidance response recorded by Kolski and Johnson (1987) who reported bowhead whales swimming rapidly away from an approaching seismic vessel at a 24 km distance.

In an analysis of marine mammals sightings recorded from seismic survey vessels in United Kingdom waters, Stone (2003) reported that responses to large gun seismic activity varied between species, with small odontocetes showing the strongest avoidance response. Responses of medium and large odontocetes (killer whales, pilot whales and sperm whales) were less marked, with sperm whales showing no observable avoidance effects (see also Rankin & Evans 1998; Davis et al. 2000; Madsen et al. 2006). Baleen whales showed fewer responses to seismic survey activity than small odontocetes, and although there were no effects observed for individual baleen whale species, fin and sei whales were less likely to remain submerged during firing activity. All baleen whales showed changes in behavioural responses further from the survey vessel (see also Ljungblad et al. 1988; McCauley 2000; Abgrall et al. 2008), and both orientated away from the vessel and altered course more often during shooting activity. The author suggests that different species adopt different strategies in response to seismic survey disturbance, with faster smaller odontocetes fleeing the survey area (e.g. Weir 2008), while larger slower moving baleen whales orientate away from and move slowly from the firing guns, possibly remaining on the surface as they do so (see also Richardson et al. 1985a, 1985b, 1986, 1995). Responses to small airguns were less, and although no difference in distance to firing and non-firing small airguns were recorded, there were fewer sightings of small odontocetes in association with firing airguns. Other reports suggest that there is little effect of seismic surveys on small odontocetes such as dolphins, as these have been reported swimming near or riding the bow-waves of operating seismic vessels (Duncan 1985; Evans & Nice 1996; Abgrall et al. 2008; but see also Schlundt et al. 2000).

McCauley et al. (1996, 2000) found no obvious evidence that humpback whales were displaced by 2D and 3D seismic surveys and no apparent gross changes in the whale’s migratory path could be linked to the seismic survey. Localised avoidance of the survey vessel during airgun operation was however noted. Whales which are not migrating but using the area as a calving or nursery ground may be more seriously affected through disturbance of suckling or resting. Potential avoidance ranges of 7-12 km by nursing animals have been suggested, although these might differ in different sound propagation conditions (McCauley et al. 2000). Disturbance of mating behaviour (which could involve a high degree of acoustic selection) by seismic noise could be of consequence to breeding animals.



4.7.5 Masking of important environmental or biological sounds

Potential interference of seismic emissions with acoustic communication in cetaceans includes direct masking of the communication signal, temporary or permanent reduction in the hearing capability of the animal through exposure to high sound levels or limited communication due to behavioural changes in response to the seismic sound source. Masking can both reduce the range over which the signals can be heard and the quality of the signal's information (Weilgart et al. 2007). Baleen whales generally appear to vocalise almost exclusively within the frequency range of the maximum energy of seismic sounds, i.e. under 1 kHz. Whales may respond to masking by calling more frequently, calling louder, calling less frequently (Weilgart et al. 2007) or showing no change in calling behaviour (Madsen et al. 2002). For example, a recent study shows that blue whales called consistently more on days when seismic exploration was taking place, presumably to compensate for the elevated ambient noise levels (Di Lorio et al. 2010). The masking effect of seismic pulses might be reduced by their intermittent production. However, the length of seismic pulses increases with distance from the source, thereby increasing the potential to cause masking at range (Gordon et al. 2004). Toothed whales vocalise at much higher frequencies, and it is likely that clicks are not masked by seismic survey noise (Goold & Fish 1998). However, due to multi-path propagation, receivers (cetaceans) can be subject to several versions of each airgun pulse, which have very different temporal and spectral properties (Madsen et al. 2006). High frequency sound is released as a by-product of airgun firing and this can extend into the mid- and high-frequency range (up to and exceeding 15 kHz) so that the potential for masking of these sound sources should be also considered (Madsen et al. 2006).

4.7.5 Indirect effects on prey species

Exposure to seismic airguns can cause hearing damage to fish (reviewed in Popper & Schilt 2008) and several studies have linked seismic exploration with short-term reductions in fish abundance and changes in distribution away from the seismic survey area (Englas et al. 1995; Slotte et al. 2004). The majority of baleen whales will undertake little feeding within breeding ground waters and rely on blubber reserves during their migrations. Therefore they may not be affected by changes in fish distribution. Although the fish and cephalopod prey of toothed whales and dolphins may be affected by seismic surveys, impacts will be highly localised and small in relation to the feeding ranges of cetacean species, but cumulative impacts within species ranges must be considered.



5. ASSESSMENT OF ACOUSTIC IMPACTS ON MARINE FAUNA

5.1. Assessment Procedure

The following convention was used to determine significance ratings in the assessment:

Rating Definition of Rating

Extent – defines the physical extent or spatial scale of the impact

Local Extending only as far as the immediate activity, limited to the survey

vessel and seismic array and their immediate surroundings

Regional Limited to the northern Namibian Coast

National Limited to the entire coastline of Namibia

International Extending beyond the borders of Namibia

Duration – the time frame over which the impact will be experienced

Short-term 0 – 5 years

Medium-term 6 – 15 years

Long-term Where the impact would cease after the operational life of the activity,

either because of natural processes or by human intervention

Permanent Where mitigation either by natural processes or by human intervention

would not occur in such a way or in such time span that the impact can be

considered transient

Intensity – establishes whether the magnitude of the impact is destructive or benign in relation

to the sensitivity of the receiving environment

Low Where natural environmental functions and processes are not affected

Medium Where the affected environment is altered, but natural functions and

processes continue, albeit in a modified way

High Where environmental functions and processes are altered to the extent

that they temporarily or permanently cease

Using the core criteria above, the significance of the impact is determined:

Significance – attempts to evaluate the importance of a particular impact, and in doing so

incorporates extent, duration and intensity


of high intensity at a regional level and endure in the long term;




of high intensity at a regional level enduring in the medium term;








Significance – attempts to evaluate the importance of a particular impact, and in doing so

incorporates extent, duration and intensity










of low intensity at a regional level, enduring in the medium term;





OR of medium intensity at a local level, enduring in the medium term.




OR of low to medium intensity at a local level, enduring in the short

term.


Zero to Very Low intensity with any combination of extent and

duration.

UNKNOWN Where it is not possible to determine the significance of an impact.

Status of the Impact – describes whether the impact would have a negative, positive or zero

effect on the affected environment

Positive The impact benefits the environment

Negative The impact results in a cost to the environment

Neutral The impact has no effect

Probability – the likelihood of the impact occurring

Improbable Possibility very low either because of design or historic experience

Probable Distinct possibility

Highly Probable Most likely

Definite Impact will occur regardless of preventive measures

Degree of confidence in predictions – in terms of basing the assessment on available

information and specialist knowledge

Low Less than 35% sure of impact prediction.

Medium Between 35% and 70% sure of impact prediction.

High Greater than 70% sure of impact prediction



Additional criteria to be considered, which could “increase” the significance rating are:

• Permanent / irreversible impacts (as distinct from long-term, reversible impacts); • Potentially substantial cumulative effects; and • High level of risk or uncertainty, with potentially substantial negative consequences.

Additional criteria to be considered, which could “decrease” the significance rating are:

• Improbable impact, where confidence level in prediction is high. The relationship between the significance ratings after mitigation and decision-making can be broadly defined as follows:

Significance after Mitigation - considering changes in intensity, extent and duration after

mitigation and assuming effective implementation of mitigation measures

Very Low; Low Will not have an influence on the decision to proceed with the proposed

project, provided that recommended measures to mitigate negative

impacts are implemented.

Medium Should influence the decision to proceed with the proposed project,

provided that recommended measures to mitigate negative impacts are

implemented.

High; Very High Would strongly influence the decision to proceed with the proposed

project.

5.2. Assessment of Impacts

5.2.1 Impacts to Plankton

Potential impacts of seismic pulses on plankton and fish eggs and larvae would include mortality or physiological injury in the immediate vicinity of the airgun sound source. Impacts would thus be of high intensity at very close range (<5 m from the airguns) only, and no more significant than the effect of the wash from ships propellers and bow waves. As plankton distribution is naturally temporally and spatially variable and natural mortality rates are high, any impacts would thus be of low to negligible intensity across the immediate survey area and for the duration of the survey programme (short-term).

Plankton is particularly abundant in the shelf waters off Namibia, being associated with the upwelling characteristic of the area. The spatial and temporal variation in upwelling results in considerable variability in phytoplankton biomass in both longshore and offshore directions. As the majority of zooplankton are primary consumers, zooplankton biomass is strongly correlated to that of phytoplankton (i.e. low biomass immediately following upwelling, with increases tracking the development of phytoplankton blooms). Since the proposed survey area is located offshore of an upwelling cell (see Figure 7), it is expected that phytoplankton and zooplankton abundances will be seasonally variable.

The proposed seismic survey area overlaps with the summer to autumn spawning area for anchovy, pilchard and horse mackerel, but lies well offshore of cob and steenbras spawning areas (see Figure 12). Therefore, ichthyoplankton abundances in the survey area are expected



to be seasonally high. The spring to early summer spawning areas for hake, pilchard, sole and horse mackerel are located well to the south of the proposed survey area, although since the collapse of the pilchard stock these primarily spawn north of Torra Bay. The survey area will thus overlap with the spawning area for pilchards. Hake spawn and recruit throughout the year with spawning peaks occurring in early summer (Botha 1980; Olivar et al. 1988) along the shelf break off central Namibia. In Monkfish spawning is irregular but is likewise thought to occur throughout the year (Macpherson 1985), as is spawning of deep-sea red crab (Le Roux 1997). Orange Roughy in contrast have a short, intense spawning period between July and August (Boyer & Hampton 2001). Dalen et al. (1996) recommended that seismic survey activities should avoid areas of concentrated spawning or spawning migration paths by 50 km, particularly areas subjected to repeated, high intensity surveys. However, considering the spatial extent of the spawning areas, mitigation through avoidance of concentrated spawning areas is not deemed necessary in this case.

The overall potential impact of seismic noise on plankton and ichthyoplankton is thus deemed to be of VERY LOW significance both with and without mitigation. Mitigation

No direct mitigation measures for potential impacts on plankton and fish egg and larval stages are feasible or deemed necessary.

Impacts of seismic noise to plankton and ichthyoplankton

Without Mitigation Assuming Mitigation

Extent Local: limited to immediate survey area Local

Duration Short-term: for duration of survey Short-term

Intensity Low Low

Significance Very Low Very Low

Status Negative Negative

Probability Probable Probable

Confidence Medium Medium

5.2.2 Impacts to Marine Invertebrates

Although some marine invertebrates have mechanoreceptors or statocyst organs that are sensitive to hydroacoustic disturbances, most do not possess hearing organs that perceive sound pressure. Potential impacts of seismic pulses on invertebrates include physiological injury and behavioural avoidance of seismic survey areas. Masking of environmental sounds and indirect impacts due to effects on predators or prey have not been documented and are highly unlikely. Physiological injury and mortality

There is little published information on the effects of seismic surveys on invertebrate fauna. It has been postulated, however, that shellfish, crustaceans and most other invertebrates can only hear seismic survey sounds at very close range, such as less than 15 m away. This implies that only surveys conducted in very shallow water will have any detrimental



effects. As the survey would be conducted in excess of 150 m depth the received noise at the seabed would be within the far-field range, and outside of distances at which physiological injury of benthic invertebrates would be expected. The potential impact of seismic noise on physiological injury or mortality of invertebrates is thus consequently deemed of low to negligible intensity across the immediate survey area and for the survey duration and is considered to be of VERY LOW significance both with and without mitigation.

Although a causative link to seismic surveys has not been established with certainty, giant squid strandings coincident with seismic surveys have been reported (Guerra et al. 2004), the animals all having severe internal injuries that the authors suggested were indicative of having ascended from depth too quickly. Furthermore, controlled-exposure experiments during which cephalopods were subjected to low-frequency sounds resulted in permanent and substantial alterations of the sensory hair cells of the statocysts of four squid species (André et al. 2011). The potential impact of seismic noise on physiological injury or mortality of pelagic cephalopods could thus potentially be of high intensity across the immediate survey area and for the survey duration. However, as the probability of an encounter of pelagic cephalopods is considered low, the impact is deemed to be of VERY LOW significance both without and with mitigation.

No mitigation measures for potential impacts on marine invertebrates and their larvae are feasible or deemed necessary. Behavioural avoidance

Similarly, there is little published information on the effects of seismic surveys on the response of invertebrate fauna to seismic impulses. Limited avoidance of airgun sounds may occur in mobile neritic and pelagic invertebrates and is deemed to be of low intensity. Of the marine invertebrates only cephalopods are receptive to the far-field sounds of seismic airgun arrays. Although consistent avoidance has not been reported, behavioural changes have been observed at 2 – 5 km from an approaching large seismic source (McCauley et al. 2000). The received noise at the seabed would be within the far-field range, and thus outside of distances at which avoidance of benthic invertebrates would be expected, but potentially within the response range of cephalopods. The potential impact of seismic noise on invertebrate behaviour is consequently deemed of low to negligible intensity across the immediate survey area and for the survey duration and is considered to be of VERY LOW significance both with and without mitigation, and no mitigation measures are deemed necessary.

Impacts of seismic noise to marine invertebrates resulting in physiological injury




Intensity Low to high Low







Impacts of seismic noise to marine invertebrates resulting in behavioural avoidance




Intensity Low Low





5.2.3 Impacts to Fish

A review of the available literature suggests that potential impacts of seismic pulses to fish (including sharks) species could include physiological injury and mortality, behavioural avoidance of seismic survey areas, masking of environmental sounds and communication, and indirect impacts due to effects on predators or prey.

Physiological injury and mortality The greatest risk of pathological injury from seismic sound sources is for species that

establish home ranges on shallow-water reefs or congregate in inshore waters to spawn or feed, and those displaying an instinctive alarm response to hide on the seabed or in the reef rather than flee. Large demersal or reef-fish species with swim-bladders are also more susceptible than those without this organ. Such species may suffer pathological injury or severe hearing damage and adverse effects may intensify and last for a considerable time after the termination of the sound source. However, as the proposed survey area is mostly located in water depths of beyond 150 m, the received noise by demersal species at the seabed would be within the far-field range, and outside of distances at which physiological injury or avoidance would be expected.

The most likely fish species to be encountered in the survey area are the large pelagic species such as the highly migratory tuna and billfish, which occur offshore of the 100 m isobath. These large pelagic species are known to aggregate around seamounts and bathymetric features such as the Walvis Ridge to feed, and as such are expected to occur year-round in the proposed survey area, with commercial catches peaking between March and May. As the 10-month seismic survey is scheduled to commence in the fourth quarter of 2017 the likelihood of encounter tuna and billfish is high. However, given the high mobility of most large pelagic species, it is assumed that the majority of these would avoid seismic noise at levels below those where physiological injury or mortality would result. Furthermore, in many of the large pelagic species, the swim-bladders are either underdeveloped or absent, and the risk of physiological injury through damage of this organ is therefore lower. Possible injury or mortality in pelagic species could occur on initiation of a sound source at full pressure in the immediate vicinity of fish, or where reproductive or feeding behaviour override a flight response to seismic survey sounds. The potential physiological impact on pelagic species, would be of high intensity. The potential physiological impact on demersal species would, however, be insignificant as they would only be affected in the far-field range, if at all. The



duration of the impact on the population would be limited to the short-term. The impact is therefore considered to be of LOW significance without the implementation of mitigation measures, and of VERY LOW significance with mitigation measures. Behavioural avoidance

Behavioural responses such as avoidance of seismic survey areas and changes in feeding behaviours of some fish to seismic sounds have been documented at received levels of about 160 dB re 1 µPa. Recent concerns that seismic survey activities in southern Namibia and the Australian Bight are responsible for substantially reduced catches of albacore and southern bluefin tuna, respectively, however still need to be substantiated. However, according to other sources, it is probable that fluctuating tuna catches are caused by a number of variables (e.g. fluctuation of fishing effort, general decline in longfin tuna abundance and changes in fishing strategy) (Attwood 2014). This is supported by the briefing paper prepared by Dr Gabi Schneider of the GSN (Schneider & Muyongo 2013), which states that a simple correlation between seismic survey acquisition in Namibian waters and reduced tuna catches cannot be inferred and more in-depth research is required.

The potential impact on fish behaviour could therefore be of high intensity (particularly in the near-field of the airgun array), over the short to medium term with duration of the effect being less than or equal to the duration of exposure, although these vary between species and individuals, and are dependent on the properties of the received sound. Any observed effects will be limited to the immediate survey area, and are unlikely to persist for more than a few days after termination of airgun use. Consequently it is considered to be of LOW without mitigation and VERY LOW significance with mitigation. Reproductive success / spawning

Fish populations can be further impacted if behavioural responses result in deflection from migration paths or disturbance of spawning. If fish on their migration paths or spawning grounds are exposed to powerful external forces, they may be disturbed or even cease spawning altogether thereby affecting recruitment to fish stocks. The magnitude of effect in these cases will depend on the biology of the species and the extent of the dispersion or deflection. Studies undertaken experimentally exposing the eggs and larvae of various fish species to airgun sources, however, identified mortalities and physiological injuries at very close range (<5 m) only. Although the survey will overlap with various spawning areas, it will primarily be conducted at depths in excess of 150 m within the far-field range. Considering the spatial extent of the spawning areas, the wide range over which the potentially affected species occur, the low frequency and short duration of the proposed seismic survey, and that migration routes do not constitute narrow restricted paths, the impact is considered to be of LOW significance without mitigation and of VERY LOW significance with mitigation.

Similarly, any indirect effects of mortality to ichthyoplankton (assessed in Section 5.2.1) or recruitment to adult fish populations is also considered to be of VERY LOW significance both with and without mitigation. Masking of environmental sounds and communication

Communication and the use of environmental sounds by fish in the offshore environment off the southern African west coast are unknown. Impacts arising from masking of sounds are expected to be of low intensity due to the duty cycle of seismic surveys in relation to the more



continuous biological noise. Such impacts would occur across the immediate survey area and for the duration of the survey and are consequently considered of VERY LOW significance both with and without mitigation.


The assessment of indirect effects of seismic surveys on fish is limited by the complexity of trophic pathways in the marine environment. The impacts are difficult to determine, and would depend on the diet make-up of the fish species concerned and the effect of seismic surveys on the diet species. Indirect impacts of seismic surveying could include attraction of predatory species such as sharks and tunas to pelagic fish stunned by seismic noise. In such cases where feeding behaviour overrides a flight response to seismic survey sounds, injury or mortality could result if the seismic sound source is initiated at full power in the immediate vicinity of the feeding predators. Little information is available on the feeding success of large migratory species in association with seismic survey noise. Large pelagic species are known to aggregate around seamounts and bathymetric features such as the Walvis Ridge to feed. However, considering the extensive range over which large pelagic fish species can potentially feed in relation to the immediate survey area, and the low abundance of pelagic shoaling species that constitute their main prey, the impact is likely to be of VERY LOW significance both with and without mitigation.

Mitigation

Recommendations for mitigation include:

• All initiation of airgun firing to be carried out as “soft-starts” of at least 20 minutes duration, allowing fish to move out of the immediate survey area and thus avoid potential physiological injury as a result of seismic noise (JNCC 2010).

• All breaks in airgun firing of longer than 20 minutes must be followed by a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks of shorter than 20 minutes should be followed by a “soft-start” of similar duration.

• Airgun firing should be terminated if mass mortalities of fish as a direct result of shooting are observed.

Impacts of seismic noise on fish resulting in physiological injury




Intensity High Low to Medium

Significance Low Very Low


Probability Probable Improbable




Impacts of seismic noise on fish resulting in behavioural avoidance




Intensity High Medium





Impacts of seismic noise on reproductive success and spawning









Impacts of seismic noise on fish resulting in masking of sounds




Intensity Low Low



Probability Improbable Improbable

Confidence Low Low

Impacts of seismic noise on fish resulting in indirect impacts on food sources




Intensity Low Low




Confidence Low Low



5.2.4 Impacts to Seabirds

Among the marine avifauna occurring along the Namibian coast, it is only the species that feed by plunge-diving or that rest on the sea surface, which may be affected by the underwater noise of seismic surveys. Potential impacts of seismic pulses to diving birds could include physiological injury, behavioural avoidance of seismic survey areas and indirect impacts due to effects on prey. The seabird species are all highly mobile and would be expected to flee from approaching seismic noise sources at distances well beyond those that could cause physiological injury, but initiation of a sound source at full power in the immediate vicinity of diving seabirds could result in injury or mortality where feeding behaviour overrides a flight response to seismic survey sounds. The potential for physiological injury or behavioural avoidance in non-diving seabird species is considered INSIGNIFICANT and will not be discussed further here. Physiological injury

The continuous nature of the intermittent seismic survey pulses suggest that diving birds would hear the sound sources at distances where levels would not induce mortality or injury, and consequently be able to flee an approaching sound source. The potential for physiological impact of seismic noise on diving birds could be of high intensity but would be limited to the immediate survey area and survey duration (short term). Of the plunge diving species that occur along the Namibian coastline, only the Cape Gannet regularly feeds as far offshore as 100 km, the rest foraging in nearshore areas up to 40 km from the coast. Penguins are known to forage as far as 60 km offshore and juveniles have been reported to travel up the coast regularly, being sighted as far north as southern Angola. The nearest nesting grounds for Gannets and African Penguins are at Ichaboe Island, Halifax and Possession Islands, which lie over 500 km to the south of the proposed 3D seismic survey area. Encounters are thus unlikely. The Kunene River mouth and south thereof is an important habitat for Damara Terns (Barnard 1998). The river mouth and coastline are located ~25 km east of the eastern boundary of the proposed survey area. However, as Damara Terns feed primarily in inshore waters, sheltered bays and lagoons (Braby 2011), encounter rates with offshore seismic activities is likely to be low. Due to the low likelihood of encounters with diving species, the potential physiological impact on diving species would thus be of VERY LOW significance both without and with mitigation.


Diving birds would be expected to hear seismic sounds at considerable distances as they have good hearing at low frequencies (which coincide with seismic shots). Response distances are speculative, however, as no empirical evidence is available. Behavioural avoidance by diving seabirds would be limited to within the long range of the operating airgun over the duration of the survey period. Should seismic operations encounter diving birds, the impact is likely to be of medium to high intensity. However, due to the low likelihood of encountering diving birds in the 3D survey area, the potential impact on the behaviour of diving seabirds is considered to be of LOW significance without mitigation and VERY LOW significance with mitigation.



Indirect impacts due to effects on prey

As with other vertebrates, the assessment of indirect effects of seismic surveys on diving seabirds is limited by the complexity of trophic pathways in the marine environment. The impacts are difficult to determine, and would depend on the diet make-up of the bird species concerned and the effect of seismic surveys on the diet species. No information is available on the feeding success of seabirds in association with seismic survey noise. With few exceptions, most plunge-diving birds forage on small shoaling species relatively close to the shore and are unlikely to feed extensively in the offshore waters of the proposed seismic survey area. The broad ranges of potential fish prey species (in relation to potential avoidance patterns of seismic surveys of such prey species), the low likelihood of encountering diving birds and extensive ranges over which most seabirds feed suggest that indirect impacts would be VERY LOW with and without mitigation. Other Potential Impacts

Other potential adverse interactions between seabirds and seismic surveys are (1) stranding of birds on the survey vessel due to being attracted to the vessel lights at night, and (2) oiling through accidental loss of buoyancy liquid or hydraulic fluid from the towed gear. However, while there is some potential for effects on individual seabirds through strandings or oiling, no significant effects on seabird populations are predicted, as the number of animals potentially affected will be small. The impacts are thus assessed as being INSIGNIFICANT. Mitigation

Recommendations for mitigation include:

• All initiation of airgun firing to be carried out as “soft-starts” of at least 20 minutes duration (JNCC 2010).

• A 500 m radius area to be scanned (visually during the day) by an independent observer for the presence of diving seabirds prior to the commencement of “soft starts” and these to be delayed until such time there is no significant diving seabird activity within 500 m of the vessel.

• Seabird incidence and behaviour should be recorded by an onboard Independent Observer. Any obvious mortality or injuries to seabirds as a direct result of the survey should result in temporary termination of operations.

• Any attraction of predatory seabirds (by mass disorientation or stunning of fish as a result of seismic survey activities) and incidents of feeding behaviour among the hydrophone streamers should be recorded by an onboard Independent Observer.

• If obvious mortality or injuries to diving seabirds is observed, the survey should be terminated temporarily until such time the MMO confirms that the risk to diving seabirds has been significantly reduced.

• Lighting on-board the survey vessel should be reduced to minimum safety levels to minimise stranding of pelagic seabirds on the survey vessel at night. All stranded seabirds must be retrieved and released during daylight hours.



Impacts of seismic noise on diving seabirds resulting in physiological injury




Intensity Low Low





Impacts of seismic noise on diving seabirds resulting in behavioural avoidance




Intensity Medium - High Low





Impact: Impacts of seismic noise on seabirds resulting in indirect impacts on food sources




Intensity Low Low




Confidence Low Low

Impacts of seismic surveys to seabirds through stranding or oiling




Intensity Very Low Very Low

Significance Insignificant Insignificant






5.2.5 Impacts to Turtles

Although three species of turtles occur along the west coast of southern Africa, it is only the Leatherback turtle which is likely to be encountered in the offshore waters of the survey area. The occurrence of non-breeding Green turtles has been reported from the Kunene River mouth (Barnard 1998), which lies ~25 km east of the northeastern boundary of the proposed survey area. However, abundances of both species are likely to be extremely low, comprising occasional migrants. The most likely impacts to turtles from seismic survey operations include physiological injury (including disorientation) or mortality from seismic noise or collision with or entanglement in towed seismic apparatus, behavioural avoidance of seismic survey areas, and indirect effects due to the effects of seismic sounds on prey species. Physiological injury (including disorientation) or mortality

Although no information could be sourced on physiological injury to turtle hearing as a result of seismic sounds, the overlap of their hearing sensitivity with the higher frequencies produced by airguns, suggest that turtles may be considerably affected by seismic noise. Recent evidence, however, suggests that turtles only detect airguns at close range (<10 m) or are not sufficiently mobile to move away from approaching airgun arrays (particularly if basking). Initiation of a sound source at full power in the immediate vicinity of a swimming or basking turtle would be expected to result in physiological injury. The potential impact could therefore be of high intensity, but remain within the short-term. However, as the abundance of adult turtles in the survey area is low, the likelihood of encountering turtles during the proposed survey is thus expected to be very low. The potential physiological impact on turtles is thus considered to be of LOW significance without mitigation, and VERY LOW significance with mitigation.

The potential for collision between adult turtles and the seismic vessel, or entanglement of turtles in the towed seismic equipment and surface floats, is highly dependent on the abundance and behaviour of turtles in the immediate survey area at the time of the survey. As the breeding areas for Leatherback and Green turtles occur over 1,000 km north-west of the survey area in the Republic of Congo and Gabon, and Equatorial Guinea, respectively, turtles encountered during the survey are likely to be migrating vagrants and impacts through collision or entanglement would be of low intensity and short-term. The impacts on turtles through collision or entanglement of seismic equipment is thus considered to be of VERY LOW significance both without and with mitigation.


Behavioural changes by turtles in response to seismic sounds range from apparent lack of movement away from active airgun arrays through to startle response and avoidance by fleeing an operating sound source. The impact of seismic sounds on turtle behaviour is of high intensity, but would persist only for the duration of the survey, and be restricted to the immediate survey area. Given the general extent of turtle migrations relative to the seismic survey target grid and low turtle abundance in the survey area, the impact of seismic noise on turtle migrations is deemed to be of LOW significance without mitigation and VERY LOW with mitigation.



Indirect effects due to the effects of seismic sounds on prey species

Leatherback turtles feed on jellyfish, which are pelagic and therefore have a naturally temporally and spatially variable distribution. Adverse modification of such pelagic food sources would thus be insignificant, and the effects of seismic surveys on the feeding behaviour of turtles is thus expected to be VERY LOW both with and without mitigation.


Breeding adults of sea turtles undertake large migrations between distant foraging areas and their nesting sites (which on the African West coast are >1,000 km north-west of survey area in Republic of Congo, Gabon and Equatorial Guinea). Although it is speculated that turtles may use acoustic cues for navigation during migrations, information on turtle communication is lacking. There is no information available in the literature on the effect of seismic noise in masking environmental cues and communication in turtles, but their low abundance in the survey area would suggest that the potential significance of this impact (should it occur) would be INSIGNIFICANT.

Mitigation

A number of mitigation measures are recommended for potential impacts of seismic surveys on turtles:

• All initiation of airgun firing to be carried out as “soft-starts” of at least 20 minutes duration (JNCC 2010).

• A 500 m radius area to be scanned by an independent observer for the presence of turtles prior to the commencement of “soft-starts” and these to be delayed until such time as this area is clear of turtles.

• Daylight observations of the survey region should be carried out by onboard Independent Observers and incidence of turtles and their responses to seismic shooting should be recorded.

• Seismic shooting should be terminated when obvious changes to turtle behaviour is observed from the survey vessel, or animals are observed within the immediate vicinity (within 500 m) of operating airguns and appear to be approaching firing airguns.

• Any obvious mortality or injuries to turtles as a direct result of the survey should result in temporary termination of operations.

• Ensure that ‘turtle-friendly’ tail buoys are used by the survey contractor or that existing tail buoys are fitted with either exclusion or deflector ‘turtle guards’.

Impacts of seismic noise on turtles resulting in physiological injury, or collision and

entanglement with towed equipment




Intensity High Low







Impacts of seismic noise on turtles resulting in behavioural avoidance




Intensity High Low




Confidence High High

Impacts of seismic noise on turtles resulting in indirect impacts on food sources




Intensity Low Low




Confidence Low Low

Impacts of seismic noise on turtles resulting in masking of sounds




Intensity Very Low Very Low

Significance Insignificant Insignificant



Confidence Low Low

5.2.6 Impacts to Seals

Physiological injury or mortality

The physiological effects of loud low frequency sounds on seals have not been well documented. The potential for physiological injury to seals from seismic noise is expected to be low as being highly mobile, fur seals would avoid severe sound sources at levels well below those at which discomfort occurs. Past studies suggest that noise of moderate intensity and duration is sufficient to induce temporary threshold shifts in seals, as individuals did not appear to avoid the immediate survey area. Their tendency to swim at or near the surface will also



expose them to reduced sound levels when in close proximity to an operating airgun array. The breeding colonies closest to the proposed survey are located at Cape Fria and Möwe Bay, approximately 60 km and 200 km south of the southeastern corner of the proposed survey area, respectively. The proposed 3D survey area therefore falls within the foraging range of seals from the nearby colonies. The potential impact of physiological injury to seals as a result of seismic noise is therefore deemed to be of high intensity and would be limited to the immediate survey area, although injury could extend beyond the survey duration. The significance of the impact without mitigation is LOW and VERY LOW with mitigation.


Although partial avoidance (to less than 250 m) of operating airguns has been recorded for some seals species, Cape fur seals appear to be relatively tolerant to loud noise pulses and, despite an initial startle reaction, individuals quickly reverted back to normal behaviour. The potential impact of seal behaviour in response to seismic surveys is thus considered to be of low to medium intensity and limited to the immediate survey area and duration. The significance of behavioural avoidance impacts are consequently deemed VERY LOW, both with and without mitigation. Masking of environmental sounds and communication

The use of underwater sounds for environmental interpretation and communication by Cape fur seals is unknown, although masking is likely to be limited by the low duty cycle of seismic pulses (one firing every 10 to 15 seconds). The impacts of masking are considered VERY LOW, both with and without mitigation. Indirect effects due to the effects of seismic sounds on prey species

As with other vertebrates, the assessment of indirect effects of seismic surveys on Cape fur seals is limited by the complexity of trophic pathways in the marine environment. The impacts are difficult to determine, and would depend on the diet make-up of the species (and the flexibility of the diet), and the effect of seismic surveys on the diet species. The broad ranges of fish prey species (in relation to the avoidance patterns of seismic surveys of such prey species) and the extended foraging ranges of Cape fur seals suggest that indirect impacts due to effects on predators or prey would be VERY LOW, both with and without mitigation. Mitigation

Mitigation measures recommended for potential impacts of seismic surveys on seals are:

• Daylight observations of the survey region should be carried out by onboard Marine Mammal Observers (MMOs) and the presence of seals (including number and position / distance from the vessel) and their behaviour should be recorded prior to “soft start” procedures. All initiation of airgun firing to be carried out as “soft-starts” of at least 20 minutes duration (JNCC 2010).

• “Soft start” procedures should, if possible, only commence once it has been confirmed that there is no seal activity within 500 m of the airguns. If after a period of 30 minutes seals are still within 500 m of the airguns, the normal “soft start” procedure should be allowed to commence for at least a 20-minutes duration.



• The MMO should monitor seal behaviour during “soft-starts” to determine if the seals display any obvious negative responses to the airguns and gear or if there are any signs of injury or mortality to seals as a direct result of seismic shooting operations.

• Seismic shooting should be terminated when obvious negative changes to seal behaviour are observed or there is any obvious mortality or injuries to seals as a direct result of the survey.

• The MMO’s daily report should record general seal activity, numbers and any noticeable change in behaviour.

Impacts of seismic noise on seals resulting in physiological injury




Intensity High Low





Impacts of seismic noise on seals resulting in behavioural avoidance




Intensity Low to medium Low





Impacts of seismic surveys on seals resulting in masking of sounds and communication




Intensity Low Low







Impacts of seismic surveys on seals resulting from indirect effects on their prey




Intensity Low Low





5.2.7 Impacts to Whales and Dolphins

A wide diversity of cetaceans (whales and dolphins) occur off the northern Namibian coast. The majority of migratory cetaceans in southern African waters are baleen whales (mysticetes), while toothed whales (odontocetes) may be resident or migratory. Potential impacts of seismic pulses on whales and dolphins could include physiological injury, behavioural avoidance of seismic survey areas, masking of environmental sounds and communication, and indirect impacts due to effects on prey.

When assessing the potential effects of seismic surveys on marine mammals one should bear in mind the lack of data (uncertainty) concerning the auditory capabilities and thresholds of impacts on the different species encountered and the individual variability in hearing thresholds and behavioural responses, which are likely to influence the degree of impact (Luke et al. 2009; Gedamke et al. 2011). This uncertainty and variability can have a significant bearing on how risk to marine mammals is assessed. Deficiencies in the current data prohibit a full understanding of the encounter frequencies with cetaceans or corresponding impacts of seismic surveys on marine mammals, and high resolution baseline data from the proposed survey area and survey area are necessary to fully understand the effect that seismic exploration may have on Namibia’s cetacean community.


Maximum sound pressure levels at the source of the airgun arrays would be 220-230 dB re 1 µPa @1 m, which exceed the source levels required for hearing damage (PTS and TTS) (see Table 4). Marked differences occur in the hearing capabilities of baleen whales (mysticete cetaceans) and toothed whales and dolphins (odontocete cetaceans). The vocalisation and estimated hearing range of baleen whales (centred at below 1 kHz) overlap the highest peaks of the power spectrum of airgun sounds and consequently these animals may be more affected by disturbance from seismic surveys (Nowacek et al. 2007). In contrast, the hearing of toothed whales and dolphins is centred at frequencies of between 10 and 100 kHz. These species may react to seismic shots at long ranges, but hearing damage from seismic shots is only likely to occur at close range.

Available information suggests that the animal would need to be in close proximity to operating airguns to suffer physiological injury, and being highly mobile it is assumed that they would avoid sound sources at distances well beyond those at which injury is likely to occur. However, avoidance may be complicated by the multipath nature of sound in the ocean.



Mitigation measures involving a “soft-start” procedure would help to alert cetaceans to the increasing sound level and promote movement away from the sound source. Deep-diving cetacean species may, however, be more susceptible to acoustic injury, particularly in the case of seafloor-focussed seismic surveys, where the downward focussed impulses could trap deep diving cetaceans within the survey pulse, as escaping towards the surface would result in exposure to higher sound level pulses.

The impact of physiological injury to both mysticete and odontocete cetaceans as a result of high-amplitude seismic sounds is deemed to be of high intensity, but would be limited to the immediate vicinity of operating airguns within the survey area. The proposed 3D survey is scheduled to commence in the fourth quarter of 2017 and continue for up to 10 months. Thus the proposed survey would extend into the key breeding and migration period between the beginning of June to the end of November, and encounters with humpback mother-calf pairs on their return journey from breeding grounds in equatorial West Africa are highly likely. Numbers of returning whales peak off Namibia in September. Resident whales and those making exploratory trips northwards from summer feeding grounds off Lüderitz may also be encountered. Assuming the survey will be undertaken over a 10-month period through the key migration and breeding period for whales, the impact is therefore considered to be of MEDIUM to HIGH significance without mitigation and LOW significance with mitigation.

Behavioural disturbance

Avoidance of seismic survey activity by cetaceans, particularly mysticete species, begins at distances where levels of approximately 150 to 180 dB are received. More subtle alterations in behaviour may occur at received levels of 110 dB. Although behavioural avoidance of seismic noise in the immediate survey area by baleen whales is highly likely, such avoidance is generally considered of minimal impact in relation to the distances of migrations of the majority of baleen whale species. The proposed 3D survey area overlaps with the migration route of humpback whales and other baleen whale species. As it is proposed to commence with the survey in the fourth quarter of 2017, interactions with migrating whales are thus highly likely.

The timing of the survey relative to seasonal feeding and breeding cycles (such as those observed in migrating baleen whales) may influence the degree of stress induced by noise exposure (Tyack 2008). Displacement from critical habitat is particularly important if the sound source is located at an optimal feeding or breeding ground or areas where mating, calving or nursing occurs. The proposed survey area, which is located beyond the 150 m isobath does not overlap with such known inshore areas, however the paucity of fine scale data from offshore Namibian waters on the distribution and seasonal occurrence of most cetacean species prevents prediction where such critical habitat might be with any certainty. The proposed 3D survey area, however, overlap with migration routes of humpback whales to and from their breeding grounds. Although encounter rates peak in migration periods, humpback and right whales are found in southern African West Coast waters year round, although encounters with the latter will be unlikely. Other baleen whale species are also found year round or have seasonal occurrences which are not well known, but existing data shows year-round presence of mysticetes.

The potential impact of behavioural avoidance of seismic survey areas by mysticete cetaceans is considered to be of high intensity, across the survey area and for the duration of the survey. As the proposed survey (up to 10 months in duration) is scheduled to commence in



the fourth quarter of 2017 and would extend through the key migration and breeding period from the beginning of June and the end of November, encounters with migrating whales, especially mother-calf pairs are highly likely. Resident whales and those making exploratory trips from summer feeding grounds may also be encountered. Considering the distribution ranges of most species of cetaceans, the impact of seismic surveying is considered of MEDIUM to HIGH significance before mitigation. Scheduling surveys to avoid the typical winter migration periods (June to November) of baleen whales, is the most effective mitigation measure proposed for reducing the frequency of encounters with mysticete cetaceans. If possible, the survey exclusion period should be extended to the end of January, as several of the large whale species remain abundant off the southern Namibian coast during this period. If surveying during the December / January period cannot be avoided, additional mitigation measures (PAM and thermal imaging cameras) should be implemented, and although the intensity of potential impacts would remain high, significance with mitigation would be LOW.

Information available on behavioural responses of toothed whales and dolphins to seismic surveys is more limited than that for baleen whales. No seasonal patterns of abundance are known for odontocetes occupying the proposed study area and there is less evidence of avoidance of seismic surveys by toothed whales (including dolphins). A precautionary approach to avoiding impacts is thus recommended, and consequently the impact of seismic survey noise on the behaviour of toothed whales is considered to be of medium intensity over the survey area and duration. The endemic Heaviside’s dolphin has a restricted distribution on the continental shelf in waters <200 m depth and therefore primarily inshore of the proposed survey area, although they do move offshore to feed at night. Encounters with the isolated coastal population of common bottlenose dolphins is also highly likely. A number of other toothed whale species, however, have a more pelagic distribution thus occurring further offshore and potentially within the survey area, with species diversity and encounter rates likely to be highest on the shelf slope. The overall significance will therefore vary between species, and consequently ranges between LOW and VERY LOW before mitigation and VERY LOW with mitigation.


Baleen whales appear to vocalise almost exclusively within the frequency range of the maximum energy of seismic survey noise, while toothed whales vocalise at frequencies higher than these. As the by-product noise in the mid-frequency range can travel far (at least 8 km) and extend up to 22 kHz (Goold & Fish 1998), masking of communication sounds produced by whistling dolphins and blackfish1 is likely. In the migratory baleen whale species, vocalisation increases once they reach the breeding grounds and on the return journey in December – January when accompanied by calves, so is likely to be seasonally high in the impact area. The effect of masking may, however, be reduced by the intermittent nature of seismic pulses (Gordon et al. 2003). Since the proposed survey (up to 10 months in duration) is planned to commence in the fourth quarter of 2017 and would extend through the key migration and breeding period from the beginning of June and the end of November, the intensity of impact on baleen whales is likely to vary seasonally from low (during non-migration periods) to high (during migration periods or when feeding in the area) over the immediate survey area and

1 The term blackfish refers to the delphinids: Melon-headed whale, Killer whale, Pygmy Killer Whale, False Killer Whale, Long-finned Pilot Whale and Short-finned Pilot Whale.



duration, but high in the case of toothed whales. For mysticetes and odontocetes the significance is rated as MEDIUM without mitigation and LOW with mitigation. Indirect impacts due to effects on prey

As with other vertebrates, the assessment of indirect effects of seismic surveys on resident odontocete cetaceans is limited by the complexity of trophic pathways in the marine environment. However, it is likely that both fish and cephalopod prey of toothed whales and dolphins may be affected over limited areas, although the impacts are difficult to determine. Although the majority of baleen whales undertake little feeding within breeding ground waters, there is recent evidence that certain upwelling centres may be utilised as low latitude feeding ground by both Southern Right and Humpback whales during summer. The broad ranges of prey species (in relation to the avoidance patterns of seismic surveys of such prey species) suggest that indirect impacts due to effects on prey would be of VERY LOW significance with and without mitigation. Other potential impacts

Given the slow speed (about 4 - 6 kts) of the vessel while towing the seismic array, ship strikes are also unlikely. Entanglement in gear is, however, possible. Mitigation

Mitigation measures to reduce the impact of seismic survey impulses on cetaceans include:

• Avoid planning seismic surveys during the movement of migratory cetaceans (particularly baleen whales) from their southern feeding grounds into low latitude waters (June to November), and ensure that migration paths are not blocked by seismic operations. Thus it is recommded that the proposed survey be undertaken in two phases avoiding this key breeding and migration period. If possible, the survey exclusion period should be extended to the end of January, as several of the large whale species remain abundant off the Namibian coast during this period. If surveying during the December / January period cannot be avoided, Passive Acoustic Monitoring (PAM) technology (see below) in combination with thermal imaging cameras must be implemented 24-hours a day;

• As no seasonal patterns of abundance are known for odontocetes occupying the proposed study area, a precautionary approach to avoiding impacts throughout the year is recommended.

• Survey vessels should accommodate dedicated independent MMOs with experience in seabird, turtle and marine mammal identification and observation techniques, to carry out daylight observations of the survey region and record incidence of marine mammals, and their responses to seismic shooting. Data collected should include position, distance from the vessel, swimming speed and direction, and obvious changes in behaviour (e.g. startle responses or changes in surfacing/diving frequencies, breathing patterns). The identification and the behaviour of the animals must be recorded accurately along with current seismic noise levels.



• Initiation of firing is only to begin after observations by MMOs2 have deemed the visual area around the vessel to a distance of 500 m to be clear of all large cetacean species for at least 30 minutes3 prior to firing, so that deep- or long-diving species can be detected. In the case of small cetacean (<3 m in overall length), which are common in inshore waters and often attracted to survey vessels, “soft start” procedures should, if possible, only commence once it has been confirmed that there is no small cetacean activity within 500 m of the airguns. If after a period of 30 minutes small cetaceans are still within 500 m of the airguns, the normal “soft start” procedure should be allowed to commence for at least a 20-minutes duration. The MMO should monitor small cetacean behaviour during “soft starts” to determine if the animals display any obvious negative responses to the airguns and gear or if there are any signs of injury or mortality as a direct result of seismic shooting operations.

• All breaks in airgun firing of longer than 20 minutes must be followed by a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks shorter than 20 minutes should be followed by a “soft-start” of similar duration.

• Seismic shooting should be terminated when obvious changes to cetacean behaviour is observed from the survey vessel, or animals are observed within the immediate vicinity (within 500 m) of operating airguns and appear to be approaching firing airgun.

• All data recorded by MMOs should at minimum form part of a survey close–out report. Furthermore, daily or weekly reports should be forwarded to the necessary authorities to ensure compliance with the mitigation measures.

• Marine mammal incidence data and seismic source output data arising from surveys should be made available on request to the Ministry of Fisheries and Marine Resources for analyses of survey impacts in local waters.

• All survey vessels must be fitted with Passive Acoustic Monitoring (PAM) technology, which detects animals through their vocalisations. As the survey is taking place in waters beyond 150 m depth where both inshore species (Heavisides dolphins) and sperm whales are likely to be encountered, the use of PAM 24-h a day is highly recommended. As a minimum, PAM technology must be used during the 30-minute pre-watch period and when surveying at night or during adverse weather conditions and thick fog. The PAM hydrophone streamer should ideally be towed behind the airgun array to minimise the interference of vessel noise, and be fitted with two hydrophones to allow directional detection of cetaceans.

• Survey vessels should also be fitted with thermal imaging cameras, which use infrared (IR) technology to detect the heat contrast between the marine mammal and the ocean. Advanced camera systems are capable of simultaneously monitoring 360° around a vessel and are capable of detecting smaller odontocetes at distances of several 100 m, while blows from large baleen whales can be seen at distances of up several kms. The IR camera system offers observations possibilities at night, improved detection during daylight hours, and also allows precise measurement of the distance of

2 Dec to end June: visually and PAM technology during the day and using PAM and Infra-red technology at night or during

periods of poor daytime visibility; Feb to end June: visually during the day and using PAM technology at night or during

periods of poor daytime visibility). 3 The JNCC Guidelines state this should be extended to 60 minutes for deep-diving species when surveying in deeper water

(>200 m). However, since the proposed survey is largely inshore of the expected range of sperm whales and sightings in the

survey area are expected to be very low, the recommended 30 minute period is considered adequate.



the marine mammal to the seismic vessel (Weissenberger & Zitterbard 2012; Zitterbard et al. 2013).

Potential impact of seismic noise to mysticete cetaceans.

Impacts of seismic noise on baleen whales resulting in physiological injury





Significance Medium to High Low


Probability Highly Probable Probable


Impacts of seismic noise on baleen whales resulting in behavioural avoidance




Intensity High Low

Significance Medium to High Low




Impacts of seismic surveys on baleen whales resulting in masking of sounds and communication




Intensity Low to High Low

Significance Medium Low




Impacts of seismic surveys on baleen whales resulting from indirect effects on their prey




Intensity Low Low







Potential impact of seismic noise to odontocete cetaceans.

Impacts of seismic noise on toothed whales and dolphins resulting in physiological injury





Significance Medium - High Very Low




Impacts of seismic noise on toothed whales and dolphins resulting in behavioural avoidance




Intensity Medium Low to Medium

Significance Very Low – Low (species specific) Very Low




Impacts of seismic surveys on toothed whales and dolphins resulting in masking of sounds and

communication




Intensity High Low

Significance Medium Low




Impacts of seismic surveys on toothed whales and dolphins resulting from indirect effects on

their prey




Intensity Low Low







6. CONCLUSIONS AND RECOMMENDATIONS

6.1. Conclusions

If all environmental guidelines, and appropriate mitigation measures recommended in this report, are implemented, there is no reason why the proposed seismic survey should not proceed. The proposal to conduct the survey over a 10-month period through the key migration and breeding period for whales, however, requires that additional mitigation measures need to be implemented to ensure that potential impacts be minimised. To this end it is recommended that the survey be split over two late-summer/early-winter seasons (February to June) so as to avoid the cetacean migration and breeding periods. It should also be kept in mind that some of the migratory species are now present year round off the Namibian coast. Data collected by independent onboard observers should form part of a survey close–out report to be forwarded to the necessary authorities, and any incidence data and seismic source output data arising from surveys should be made available for analyses of survey impacts in Southern African waters.

The assessments of impacts of seismic sounds provided in the scientific literature usually consider short-term responses at the level of individual animals only, as our understanding of how such short-term effects relate to adverse residual effects at the population level are limited. Data on behavioural reactions acquired over the short-term could, however, easily be misinterpreted as being less significant than the cumulative effects over the long-term, i.e. what is initially interpreted as an impact not having a detrimental effect and thus being of low significance, may turn out to result in a long-term decline in the population. A significant adverse residual environmental effect is considered one that affects marine biota by causing a decline in abundance or change in distribution of a population(s) over more than one generation within an area. Natural recruitment may not re-establish the population(s) to its original level within several generations or avoidance of the area becomes permanent. However, the southern right whale population is reported to be increasing by 7% per annum (Best 2000) and the humpback whale by 5% per annum, over a time when seismic surveying frequency has increased, suggesting that, for these populations at least, there is no evidence of long-term negative change to population size as a direct result of seismic survey activities.

Reactions to sound by marine fauna depend on a multitude of factors including species, state of maturity, experience, current activity, reproductive state, time of day (Wartzok et al. 2004; Southall et al. 2007). If a marine animal does react briefly to an underwater sound by changing its behaviour or moving a small distance, the impacts of the change are unlikely to be significant to the individual, let alone the population as a whole (NRC 2005). However, if a sound source displaces a species from an important feeding or breeding area for a prolonged period, impacts at the population level could be significant.

The significance of the impacts both before and after mitigation are summarised in the table overleaf.

6.2. Recommended Mitigation Measures

Detailed mitigation measures for seismic surveys in other parts of the world are provided by Weir et al. (2006), Compton et al. (2007) and US Department of Interior (2007). Many of the international guidelines presented in these documents are extremely conservative as they are designed for areas experiencing repeated, high intensity surveys and harbouring particularly



Impact Significance

(before mitigation)

Significance

(after mitigation)

Plankton

Physiological injury and mortality Very Low Very Low

Marine Invertebrates

Physiological injury and mortality Very Low Very Low

Behavioural avoidance Very Low Very Low

Fish

Mortality and/or physiological injury Low Very Low

Avoidance behaviour Low Very Low

Reproductive success / spawning Low Very Low

Masking of sounds Very Low Very Low

Indirect impacts on food sources Very Low Very Low

Seabirds

Physiological injury Very Low Very Low



Stranding and oiling Insignificant Insignificant

Turtles

Physiological injury, collision and entanglement Low Very Low



Masking of sounds Insignificant Insignificant

Seals

Physiological injury or mortality Low Very Low

Avoidance behaviour Very Low Very Low

Masking of sounds Very Low Very Low


Whales and dolphins

Baleen whales

Physiological injury Medium - High Low

Avoidance behaviour Medium -High Low

Masking of sounds Medium Low


Toothed whales and dolphins

Physiological injury Medium - High Low

Avoidance behaviour Very Low/Low Very Low

Masking of sounds Medium Low


Other Potential Impacts

Interaction with vessel traffic Insignificant Insignificant



sensitive species, or species with high conservation status. The guidelines currently applied for seismic surveying in South African waters are those proposed in the Generic EMPR (CCA & CMS 2001), and to date these have not resulted in any known or recorded mortalities of marine mammals, turtles or seabirds. The mitigation measures proposed below are based largely on the guidelines currently accepted for seismic surveys in South Africa, but have been revised to include salient points from international guidelines discussed in the documents cited above.

• Avoid planning seismic surveys during the movement of migratory cetaceans (particularly baleen whales) from their southern feeding grounds into low latitude waters (June to November), and ensure that migration paths are not blocked by seismic operations. However, as several of the large whale species are also most abundant off the Namibian coast between September and February, the best time of year to conduct seismic operations is late summer to early winter (February - June). If surveying during this time cannot be avoided all other mitigation measures must be stringently enforced, and PAM technology (see below) in combination with thermal imaging cameras, must be implemented 24-hours a day.

• As no seasonal patterns of abundance are known for odontocetes occupying the proposed study area, a precautionary approach to avoiding impacts throughout the year is recommended.

• All breaks in air-gun firing of longer than 20 minutes must be followed by a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks shorter than 20 minutes should be followed by a “soft-start” of similar duration.

• Prior to the commencement of “soft starts” an area of 500-m radius around the survey vessel (exclusion zone) should be scanned for the presence of diving seabirds, turtles, seals and cetaceans. There should be a dedicated pre-shoot watch of at least 30 minutes for deep-diving species. “Soft starts” should be delayed until such time as this area is clear of individuals of diving seabirds, turtles and cetaceans. Soft-start should not begin until 30 minutes after the animals depart the exclusion zone or 30 minutes after they are last seen. In the case of fur seals and small odontocetes, which may occur commonly around the vessel, the presence of seals and small odontocetes (<3 m) (including number and position / distance from the vessel) and their behaviour should be recorded prior to “soft start” procedures. If possible, “soft starts” should only commence once it has been confirmed that there is no seal and small odontocetes activity within 500 m of the air-guns. However, if after a period of 30 minutes they are still within 500 m of the air-guns, the normal “soft start” procedure should be allowed to commence for at least a 20-minute duration (JNCC 2010). Their activity should be carefully monitored during “soft starts” to determine if they display any obvious negative responses to the air-guns and gear or if there are any signs of injury or mortality as a direct result of the seismic activities.

• The implementation of “soft-start” procedures of a minimum of 20 minutes’ duration on initiation of seismic surveying would mitigate any extent of physiological injury in most mobile vertebrate species as a result of seismic noise and is consequently considered a mandatory management measure for the implementation of the proposed seismic survey. “Soft start” procedures should not be initiated during times of poor visibility or darkness without the use of existing PAM technology to confirm that no cetaceans are present.



• Independent onboard MMOs and PAM operators must be appointed for the duration of the seismic survey4. The MMOs and PAM operators must have experience in seabird, turtle and marine mammal identification and observation techniques. The duties of the MMO would be to:

• Record airgun activities, including sound levels, “soft-start” procedures and pre-firing regimes;

• Observe and record responses of marine fauna to seismic shooting, including seabird, turtle, seal and cetacean incidence and behaviour and any mortality or injuries of marine fauna as a result of the seismic survey. Data captured should include species identification, position (latitude/longitude), distance from the vessel, swimming speed and direction (if applicable) and any obvious changes in behaviour (e.g. startle responses or changes in surfacing/diving frequencies, breathing patterns) as a result of the seismic activities. Both the identification and the behaviour of the animals must be recorded accurately along with current seismic sound levels. Any attraction of predatory seabirds, large pelagic fish or cetaceans (by mass disorientation or stunning of fish as a result of seismic survey activities) and incidents of feeding behaviour among the hydrophone streamers should also be recorded;

• Sightings of any injured or dead protected species (marine mammals, seabirds and sea turtles) should be recorded, regardless of whether the injury or death was caused by the seismic vessel itself. If the injury or death was caused by a collision with the seismic vessel, the date and location (latitude/longitude) of the strike, and the species identification or a description of the animal should be recorded.

• Record meteorological conditions; • Request the temporary termination of the seismic survey or adjusting of seismic

shooting, as appropriate. It is important that MMOs have a full understanding of the financial implications of terminating firing, and that such decisions are made confidently and expediently. A log of all termination decisions must be kept (for inclusion in both daily and “close-out” reports);

• Prepare daily reports of all observations, to be forwarded to the necessary authorities on a daily or weekly basis to ensure compliance with the mitigation measures.

The duties of the PAM operator would be to: • Ensure that hydrophone streamers are optimally placed within the towed array; • Confirm that there is no marine mammal activity within 500 m of the vessel prior

to commencing with the “soft-start” procedures; • Record species identification, position (latitude/longitude) and distance from the

vessel, where possible; • Record airgun activities, including sound levels, “soft-start” procedures and pre-

firing regimes; and • Request the temporary termination of the seismic survey, as appropriate.

4 One observer is the norm, but in high latitudes two are required during summer months due to the longer daylight hours. Brazilian guidelines in contrast require at least three observers to be aboard, in order to allow efficient rotation of duties and maintain full coverage.



• All breaks in airgun firing of longer than 20 minutes must be followed by a “soft-start” procedure of at least 20 minutes prior to the survey operation continuing. Breaks of shorter than 20 minutes should be followed by a “soft-start” of similar duration.

• Ensure that ‘turtle-friendly’ tail buoys are used by the survey contractor or that existing tail buoys are fitted with either exclusion or deflector 'turtle guards'.

• Seabird, turtle and marine mammal incidence data and seismic source output data arising from surveys should be made available on request to Ministry of Fisheries and Marine Resources for analyses of survey impacts in local waters.

• Seismic shooting should be terminated on observation of any obvious mortality or injuries to cetaceans, turtles, seals or large mortalities of invertebrate and fish species as a direct result of the survey. Such mortalities would be of particular concern where a) commercially important species are involved, or b) mortality events attract higher order predator and scavenger species into the seismic area during the survey, thus subjecting them to acoustic impulses. Seismic shooting should also be terminated when obvious changes to turtle, seal or cetacean behaviours are observed from the survey vessel, or turtles and cetaceans (not seals) are observed within the immediate vicinity (within 500 m) of operating airguns and appear to be approaching firing airgun5. The rationale for this is that animals at close distances (i.e. where physiological injury may occur) may be suffering from reduced hearing as a result of seismic sounds, that frequencies of seismic sound energy lies below best hearing frequencies (certain toothed cetaceans and seals), or that animals have become trapped within the ensonified area through diving behaviour.

• Should the survey schedules overlap with the start or end of the sensitive period in terms of large mammals migrating through the area, ensure that PAM technology and thermal imaging cameras are implemented to confirm that no cetaceans are present in the vicinity of the vessel, particularly when surveying at night or during adverse weather conditions and thick fog. The use of PAM is encouraged by most international guidelines as a mitigation tool to detect marine mammals through their vocalisations, particularly if species of particular conservation importance are likely to be

encountered in the proposed survey area, or where a given species or group is difficult to detect by visual observation alone. Such monitoring can provide distance and bearing of the animals from the survey vessel. Although PAM would only identify animals that are calling or vocal, it has the advantage of 24 hour per day availability as opposed to visual monitoring, which can only be confidently carried out during daylight hours, or under adequate visibility conditions. Considering that some of the migrating baleen whale species likely to be encountered offshore are listed as “Endangered” and a proportion of the southern right and humpback populations is present in Namibian waters year-round, and that the survey area overlaps with the inshore distribution of various smaller odontocete species (Heaviside’s, common, common bottlenose, and

5 Recommended safety zones in some of the international guidelines include implementation of an observation zone of 3 km radius, low-power zone of 1.5 - 2 km radius (to cater for cow-calf pairs), and safety shut-down zone of 500 m radius around the survey vessel. Alternatively, a safety zone of 160 dB root mean squared (rms) can be calculated based on site-specific sound speed profiles and airgun parameters. The application of propagation loss models to calculate safety radii based on sound pressure levels represents a more scientific approach than the arbitrary designation of a 500 m radius (see Compton et al. (2007) for details).



right whale dolphins) every effort should be made to ensure that the vessel is fitted with PAM technology.

• Survey vessels should also be fitted with thermal imaging cameras, which use infrared (IR) technology to detect the heat contrast between the marine mammal and the ocean. Advanced camera systems are capable of simultaneously monitoring 360° around a vessel and are capable of detecting smaller odontocetes at distances of several 100 m, while blows from large baleen whales can be seen at distances of up several kms. The IR camera system offers observations possibilities at night, improved detection during daylight hours, and also allows precise measurement of the distance of the marine mammal to the seismic vessel (Weissenberger & Zitterbard 2012; Zitterbard et al. 2013).



7. LITERATURE CITED

ABGRALL, P., MOULTON, V.D. & W.R. RICHARDSON. 2008. Updated Review of Scientific Information

on Impacts of Seismic Survey Sound on Marine Mammals, 2004-present. LGL Rep. SA973-1.

Rep. from LGL Limited, St. John's, NL and King City, ON, for Department of Fisheries and

Oceans, Habitat Science Branch, Ottawa, ON. 27 p. + appendices.

ANDERSEN, S. 1970. Auditory sensitivity of the harbour porpoise, Phocoena phocoena. Invest.

Cetacea 2: 255-259.

ANDRÉ, M., SOLÉ, M., LENOIR, M., DURFORT, M., QUERO, C., MAS, A., LOMBARTE, A., VAN DER

SCHAAR, M., LÓPEZ-BEJAR, M., MORELL, M., ZAUGG, S. & L. HOUÉGNIGAN, 2011. Low-

frequency sounds induce acoustic trauma in cephalopods. Front. Ecol. Environ. 9(9): 489–

493.

ATEMA, J., FAY, R.R., POPPER, A.N. & W.N. TAVOLGA, 1988. Sensory biology of aquatic animals.

Springer-Verlag, New York.

ATKINSON, L.J., 2009. Effects of demersal trawling on marine infaunal, epifaunal and fish

assemblages: studies in the southern Benguela and Oslofjord. PhD Thesis. University of

Cape Town, pp 141

ATKINSON, L.J., FIELD, J.G.& L. HUTCHINGS. 2011. Effects of demersal trawling along the west

coast of southern Africa: multivariate analysis of benthic assemblages. Marine Ecology

Progress Series 430:241-255.

ATTWOOD, C., 2014. Making a lot of noise about the potential blue economy. Through the fish eye

lens. A wide-angle perspective on commercial fishing. Maritime Review Africa: November /

December 2014.

AU, W.W.L. 1993. The Sonar of dolphins. Springer-Verlag, New York. 277p.

AU, W.W.L., NACHTIGALL, P.E. & J.L. POLOWSKI, 1999. Temporary threshold shift in hearing

induced by an octave band of continuous noise in the bottlenose dolphin. J. Acoust. Soc.

Am., 106: 2251.

AUGUSTYN C.J., LIPINSKI, M.R. and M.A.C. ROELEVELD. 1995. Distribution and abundance of

sepioidea off South Africa. S. Afr. J. Mar. Sci. 16: 69-83.

AWBREY, F.T., THOMAS, J.A. & R.A. KASTELIN, 1988. Low frequency underwater hearing sensitivity

in belugas, Delphinapterus leucas. J. Acoust. Soc. Am., 84(6): 2273-2275.

BACKUS, R.H. & W.E. SCHEVILL, 1966. "Physter clicks," In: K. S. Norris (Ed.) Whales, dolphins and

porpoises, University of California Press, Berkeley and Los Angeles.

BAILEY, G.W. 1991. Organic carbon flux and development of oxygen deficiency on the modern

Benguela continental shelf south of 22°S: spatial and temporal variability. In: TYSON,

R.V., PEARSON, T.H. (Eds.), Modern and Ancient Continental Shelf Anoxia. Geol. Soc.

Spec. Publ., 58: 171–183.

BAILEY, G.W. 1999. Severe hypoxia and its effect on marine resources in the southern Benguela

upwelling system. Abstract, International Workshop on Monitoring of Anaerobic

processes in the Benguela Current Ecosystem off Namibia.



BAILEY, G.W., BEYERS, C.J. DE B. & S.R. LIPSCHITZ, 1985. Seasonal variation of oxygen deficiency

in waters off southern South West Africa in 1975 and 1976 and its relation to catchability

and distribution of the Cape rock-lobster Jasus lalandii. S. Afr. J. Mar. Sci., 3: 197-214.

BAILEY G.W. & P. CHAPMAN, 1991. Chemical and physical oceanography. In: Short-term variability

during an Anchor Station Study in the southern Benguela Upwelling system. Prog.

Oceanogr., 28: 9-37.

BAIN, D.E., KREITE, B. & M.E. DAHLHEIM, 1993. Hearing abilities of killer whales (Orcinus orca). J.

Acoust. Soc. Am., 93(3,pt2): 1929.

BALCOMB, K.C. & D.E. CLARIDGE, 2001. A mass stranding of cetaceans caused by naval sonar in the

Bahamas. Bahamas J. Sci., 8(2): 1-12.

BANKS, A. BEST, P.B., GULLAN, A., GUISSAMULO, A., COCKCROFT, V. & K. FINDLAY, 2011. Recent

sightings of southern right whales in Mozambique. Document SC/S11/RW17 submitted to

IWC Southern Right Whale Assessment Workshop, Buenos Aires 13-16 Sept. 2011.

BARENDSE, J., THORNTON, M.T., ELWEN, S.E. & P.B. BEST, 2002. Migrations of humpback whales

on the West Coast of South Africa: preliminary results. Paper SC/54/H21 submitted to the

Scientific Committee of the International Whaling Commission, Shimonoseki, Japan,

April/May 2002.

BARENDSE, J., BEST, P.B., THOMTON, M., POMILLA, C. CARVALHO, I. & H.C. ROSENBAUM, 2010.

Migration redefined ? Seasonality, movements and group composition of humpback whales

Megaptera novaeangliae off the west coast of South Africa. Afr. J. mar. Sci., 32(1): 1-22.

BARENDSE, J., BEST, P.B., THORNTON, M., ELWEN, S.H., ROSENBAUM, H.C., CARVALHO, I.,

POMILLA, C., COLLINS, T.J.Q. & M.A. MEŸER, 2011. Transit station or destination?

Attendance patterns, regional movement, and population estimate of humpback whales

Megaptera novaeangliae off West South Africa based on photographic and genotypic

matching. African Journal of Marine Science, 33(3): 353-373.

BARGER, J.E. & W.R. HAMBLEN. 1980. “The air gun impulsive underwater transducer”. J. Acoust.

Soc. Am., 68(4): 1038-1045.

BARNARD, P., 1998. Biological diversity in Namibia - a country study. Namibian National

Biodiversity Task Force, Windhoek.

BERG, J.A. & R.I.E. NEWELL, 1986. Temporal and spatial variations in the composition of seston

available to the suspension-feeder Crassostrea virginica. Estuar. Coast. Shelf. Sci., 23: 375–

386.

BERGEN, M., WEISBERG, S.B., SMITH, R.W., CADIEN, D.B., DALKEY, A., MONTAGNE, D.E., STULL,

J.K., VELARDE, R.G. & J. ANANDA RANASINGHE. 2001. Relationship between depth,

sediment, latitude and the structure of benthic infaunal assemblages on the mainland shelf

of southern California. Marine Biology 138:637-647.

BEST, P.B., 1990. Trends in the inshore right whale population off South Africa, 1969-1987. Marine

Mammal Science, 6: 93-108.

BEST, P,B., 1994. A review of the catch statistics for modern whaling in Southern Africa, 1908–

1930. Reports to the International Whaling Commission 44: 467–485.



BEST, P.B., 2000. Coastal distribution, movements and site fidelity of right whales (Eubalaena

australis) off South Africa, 1969-1998. S. Afr. J. mar. Sci., 22: 43 – 56.

BEST, P.B., 2001. Distribution and population separation of Bryde’s whale Balaenoptera edeni off

southern Africa. Mar. Ecol. Prog. Ser., 220: 277 – 289.

BEST, P.B., 2007. Whales and Dolphins of the Southern African Subregion. Cambridge University

Press, Cape Town, South Africa.

BEST, P.B. & C. ALLISON, 2010. Catch History, seasonal and temporal trends in the migration of

humpback whales along the west coast of southern Africa. IWC sc/62/SH5.

BEST, P.B., BUTTERWORTH, D.S. & L.H. RICKETT, 1984. An assessment cruise for the South African

inshore stock of Bryde’s whale (Balaenoptera edeni). Report of the International Whaling

Commission, 34: 403-423.

BEST, P.B. & C.H. LOCKYER, 2002. Reproduction, growth and migrations of sei whales Balaenoptera

borealis off the west coast of South Africa in the 1960s. South African Journal of Marine

Science, 24: 111-133.

BEST P.B., MEŸER, M.A. & C. LOCKYER, 2010. Killer whales in South African waters – a review of

their biology. African Journal of Marine Science. 32: 171–186.

BEST, P.B., SEKIGUCHI, K. & K.P. FINDLAY, 1995. A suspended migration of humpback whales

Megaptera novaeangliae on the west coast of South Africa. Marine Ecology Progress Series,

118: 1–12.

BEYERS, C.J. DE B., 1979. Stock assessment and some morphometric and biological characteristics

of the rock lobster Jasus lalandii on Marshall Rocks, its main commercial fishing area off

South West Africa, 1971-1974. Investl. Rep. Sea Fish. Brch S. Afr., 117: 1-26.

BEYERS, C.J. DE B., C.G. WILKE & P.C. GOOSEN, 1994. The effects of oxygen deficiency on growth,

intermoult period, mortality and ingestion rates of aquarium-held juvenile rock lobster

Jasus lalandii. S. Afr. J. Mar. Sci., 14: 79-88.

BIANCHI, G., HAMUKUAYA, H. & O. ALVHEIM, 2001. On the dynamics of demersal fish assemblages

off Namibia in the 1990s. South African Journal of Marine Science 23: 419-428.

BICKERTON, I.B. & R.A. CARTER, 1995. Benthic Macrofauna Distributions on the Inner Continental

Shelf off Lüderitz. In: CSIR, 1995. Environmental Impact Assessment for the proposed

mining of Concession Area M46/3/1607 off Lüderitz Bay: Namibia. CSIR Report EMAS-

C95040b, Stellenbosch, South Africa.

BIRCH G.F., ROGERS J., BREMNER J.M. & G.J. MOIR, 1976. Sedimentation controls on the

continental margin of Southern Africa. First Interdisciplinary Conf. Mar. Freshwater Res. S.

Afr., Fiche 20A: C1-D12.

BOHNE, B.A., THOMAS, J.A. YOHE, E. & S. STONE, 1985. Examination of potential hearing damage

in Weddell seals (Leptonychotes weddellii) in McMurdo Sound, Antarctica. Antarctica

Journal of the United States, 19(5): 174-176.

BOHNE, B.A., BOZZAY, D.G. & J.A. THOMAS, 1986. Evaluation of inner ear pathology in Weddell

seals. Antarctic Journal of the United States, 21(5): 208.



BOOMAN, C., LEIVESTAD, H. & J. DALEN, 1992. Effects of Air-gun Discharges on the Early Life Stages

of Marine Fish. Scandinavian OIL-GAS Magazine, Vol. 20 – No 1/2 1992.

BOOMAN, C., DALEN, J., LEIVESTAD, H., LEVSEN, A., VAN DER MEEREN, T. & K. TOKLUM, 1996.

Effekter av luftkanonskyting på egg, larver og yngel. Undersøkelser ved

Havforskningsinstituttet og Zoologisk Laboratorium, UiB. (Engelsk sammendrag og

figurtekster). Havforskningsinstituttet, Bergen. Fisken og Havet, 3 (1996). 83pp.

BOWLES, A.E., SMULTEA, M., WURSIG, B., DE MASTER, D.P. & D. PALKA, 1991. Biological survey

effort and findings from the Heard Island feasibility test 19 January – 3 February 1991.

Report from Hubbs/Sea World Research Institute, San Diego, California. pp102.

BOWLES, A.E. & S.J. THOMPSON. 1996. A review of nonauditory physiological effects of noise on

animals (A). J. Acoust. Soc. Am., 100(4): 2708-2708.

BOYD, A..J. & G.P.J. OBERHOLSTER, 1994. Currents off the west and south coasts of South Africa.

S. Afr. Shipping News and Fish. Ind. Rev., 49: 26-28.

BRABY, J., 2011. The Biology and Conservation of the Damara Tern in Namibia. PhD thesis,

University of Cape Town, 260pp.

BRANCH, G.M. & C.L. GRIFFITHS, 1988. The Benguela ecosystem part V: the coastal zone.

Oceanog. Mar. Biol. Ann. Rev., 26: 395-486.

BRANCH, G. M., GRIFFITHS, C. L., BRANCH, M. L. & L. E. BECKLEY, 1994. Two Oceans - A Guide to

the Marine Life of Southern Africa. David Philip, Cape Town, pp 353.

BRANCH, T.A., STAFFORD, K.M., PALACIOS, D.M., ALLISON, C., BANNISTER, J.L., BURTON, C.L.K.,

CABRERA, E., CARLSON, C.A., GALLETTI VERNAZZANI, B., GILL, P.C., HUCKE-GAETE, R.,

JENNER, K.C.S., JENNER, M.-N.M., MATSUOKA, K., MIKHALEV, Y.A., MIYASHITA, T.,

MORRICE, M.G., NISHIWAKI, S., STURROCK, V.J., TORMOSOV, D., ANDERSON, R.C., BAKER,

A.N., BEST, P.B., BORSA, P., BROWNELL JR, R.L., CHILDERHOUSE, S., FINDLAY, K.P.,

GERRODETTE, T., ILANGAKOON, A.D., JOERGENSEN, M., KAHN, B., LJUNGBLAD, D.K.,

MAUGHAN, B., MCCAULEY, R.D., MCKAY, S., NORRIS, T.F., OMAN WHALE AND DOLPHIN

RESEARCH GROUP, RANKIN, S., SAMARAN, F., THIELE, D., VAN WAEREBEEK, K. & R.M.

WARNEKE, 2007. Past and present distribution, densities and movements of blue whales in

the Southern Hemisphere and northern Indian Ocean. Mammal Review, 37 (2): 116-175.

BRANDÃO, A., BEST, P.B. & D.S. BUTTERWORTH, 2011. Monitoring the recovery of the southern

right whale in South African waters. Paper SC/S11/RW18 submitted to IWC Southern Right

Whale Assessment Workshop, Buenos Aires 13-16 Sept. 2011.

BREEZE, H., DAVIS, D.S. BUTLER, M. & V. KOSTYLEV, 1997. Distrbution and status of deep sea corals

off Nova Scotia. Marine Issues Special Committee Special Publication No. 1. Halifax, NS:

Ecology Action Centre. 58 p.

BREMNER, J.M., ROGERS, J. & J.P. WILLIS, 1990. Sedimentological aspects of the 1988 Orange River

floods. Trans. Roy. Soc. S. Afr. 47 : 247-294.

BROWN, P.C. 1984. Primary production at two contrasting nearshore sites in the southern Benguela

upwelling region, 1977-1979. S. Afr. J. mar. Sci., 2 : 205-215.



BROWN, P.C. & J.L. HENRY, 1985. Phytoplankton production, chlorophyll a and light penetration in

the southern Benguela region during the period between 1977 and 1980. In: SHANNON, L.V.

(Ed.) South African Ocean Colour and Upwelling Experiment. Cape Town, SFRI : 211-218.

BRICELJ, V.M. & R.E. MALOUF, 1984. Influence of algal and suspended sediment concentrations on

the feeding physiology of the hard clam Mercenaria mercenaria. Mar. Biol., 84: 155–165.

BUDELMANN, B.U., 1988. Morphological diversity of equilibrium receptor systems in aquatic

invertebrates. In: ATEMA, J. et al., (Eds.), Sensory Biology of Aquatic Animals, Springer-

Verlag, New York, : 757-782.

BUDELMANN, B.U., 1992. Hearing in crustacea. In: WEBSTER, D.B. et al. (Eds.), Evolutionary

Biology of Hearing, Springer-Verlag, New York, : 131-139.

BUSCAINO, G., FILICIOTTO, F., BUFFA, G., BELLANTE, A., DI STEFANO, V., ASSENZA, A., FAZIO, F.,

CAOLA, G. & S. MAZZOLA, 2010. Impact of an acoustic stimulus on the motility and blood

parameters of European sea bass (Dicentrarchus labrax L.) and gilthead sea bream (Sparus

aurata L.). Marine Environmental Research, 69(3): 136-142.

BUSTAMANTE, R.H., 1994. Patterns and causes of intertidal community structure around the coast

of southern Africa. University of Cape Town. PhD Thesis.

CARDER, D.A. & S.H. RIDGWAY, 1990. Auditory brainstem response in a neonatal sperm whale,

Physeter spp. J Acoust. Soc. Am., 88(suppl 1): S4.

CARTER, R.A. & S. COLES, 1998. Saldanha Bay General Cargo Quay Construction: Monitoring of

suspended sediment distributions generated by dredging in Small Bay. CSIR Report Env-

S98100. 26pp.

CARVALHO, I., LOO, J., COLLINS, T., POMILLA, C., BEST, P.B., HERSCH, R., LESLIE, M.S., & H.C.

ROSENBAUM, 2010. Temporal patterns of population structure of humpback whales in West

coast of Africa (B stock). Paper SC/62/SH8 Submitted to the Scientific Committee of the

International Whaling Commission. 1–13.

CETUS PROJECTS CC, 2007. Specialist report on the environmental impacts of the proposed

Ibhubesi Gas Field on marine flora and fauna. Document prepared for CCA Environmental

(Pty) Ltd., 35 Roeland Square, 30 Drury Lane, Cape Town, 8001.

CETUS PROJECTS CC, 2008. Specialist Report - Potential Environmental Impacts of Proposed 2D and

3D Seismic Surveys, Namibia. Document prepared for CCA Environmental (Pty) Ltd., 35

Roeland Square, 30 Drury Lane, Cape Town, 8001.

CHAPMAN, C.J. & A.D. HAWKINS, 1973. A field study of hearing in the cod, Gadus morhua. Journal

of Comparative Physiology, 85:147-167.

CHAPMAN, P. & L.V. SHANNON, 1985. The Benguela Ecosystem. Part II. Chemistry and related

processes. Oceanogr. Mar. Biol. Ann. Rev., 23: 183-251.

CHIVERS, S., LEDUC, R., ROBERTSON, K., BARROS, N. & A. DIZON, 2004. Genetic variation of Kogia

spp. With preliminary evidence for two species of Kogia sima. Marine Mammal Science, 21:

619-634.



CHRISTIAN, J.R., MATHIEU, A., THOMSON, D.H., WHITE, D. & R.A. BUCHANAN, 2003. Effects of

Seismic Energy on Snow Crab (Chionoecetes opilio). Report from LGL Ltd. Og Oceans Ltd.

for the National Energy Board, File No.: CAL-1-00364, 11 April 2003. 91pp.

CHRISTIE, N.D., 1974. Distribution patterns of the benthic fauna along a transect across the

continental shelf off Lamberts Bay, South Africa. Ph.D. Thesis, University of Cape Town, 110

pp & Appendices.

CHRISTIE, N.D., 1976. A numerical analysis of the distribution of a shallow sublittoral sand

macrofauna along a transect at Lambert’s Bay, South Africa. Transactions of the Royal

Society of South Africa, 42: 149-172.

CHRISTIE N.D. & A.G. MOLDAN, 1977. Effects of fish factory effluent on the benthic macro-fauna of

Saldanha Bay. Marine Pollution Bulletin, 8: 41-45.

CLARK, M.R., O’SHEA, S., TRACEY, D. & B. GLASBY, 1999. New Zealand region seamounts. Aspects

of their biology, ecology and fisheries. Report prepared for the Department of Conservation,

Wellington, New Zealand, August 1999. 107 pp.

CLIFF, G., 1982. Seasonal variation in the contribution by phytoplankton, bacteria, detritus and

inorganic nutrients to a rocky shore ecosystem. Trans. roy. Soc. S. Afr. 44: 523-538.

COCKCROFT, A.C, SCHOEMAN, D.S., PITCHER, G.C., BAILEY, G.W.& D.L. VAN ZYL, 2000. A mass

stranding, or ‘walk out’ of west coast rock lobster, Jasus lalandii, in Elands Bay, South

Africa: Causes, results and implications. In: VON VAUPEL KLEIN, J.C.& F.R. SCHRAM (Eds),

The Biodiversity Crisis and Crustacea: Proceedings of the Fourth International Crustacean

Congress, Published by CRC press.

CODARIN, A., WYSOCKI, L. E., LADICH, F. & M. PICCIULIN, 2009. Effects of ambient and boat noise

on hearing and communication in three fish species living in a Marine Protected Area

(Miramare, Italy). Mar. Poll. Bull. 58: 1880-1887.

COETZEE, J.C., VAN DER LINGEN, C.D., HUTCHINGS, L. & T.P. FAIRWEATHER, 2008. Has the fishery

contributed to a major shift in the distribution of South African sardine? ICES Journal of

Marine Science 65: 1676–1688.

COLEY, N.P. 1994. Environmental impact study: Underwater radiated noise. Institute for Maritime

Technology, Simon's Town, South Africa. pp. 30.

COLEY, N.P. 1995. Environmental impact study: Underwater radiated noise II. Institute for

Maritime Technology, Simon's Town, South Africa. pp. 31.

COLLINS, T., CERCHIO, S., POMILLA, C., LOO, J., CARVALHO, I., NGOUESSONO, S. & H.C.

ROSENBAUM, 2008. Revised estimates of abundance for humpback whale breeding stock B1:

Gabon. Paper SC60/SH28 submitted to the 60th Meeting of the Scientific Committee of the

International Whaling Commission. www.iwcoffice.org

COMPAGNO, L.J.V., EBERT, D.A. and P.D. COWLEY. 1991. Distribution of offshore demersal

cartilaginous fish (Class Chondrichthyes) off the West Coast of southern Africa, with notes

on their systematics. S. Afr. J. Mar. Sci. 11: 43-139.

COMPTON, R, GOODWIN, L., HANDY, R. & V. ABBOTT, 2007. A critical examination of worldwide

guidelines for minimising the disturbance to marine mammals during seismic surveys.

Marine Policy, doi:10.1016/j.marpol.2007.05.005



COX, T.M. and 35 others. 2006. Understanding the impacts of anthropogenic sound on beaked

whales. J. Cetacean Res. Manage., 7(3): 177-187.

CRAWFORD R.J.M., RYAN P.G. and A.J. WILLIAMS. 1991. Seabird consumption and production in the

Benguela and western Agulhas ecosystems. S. Afr. J. Mar. Sci. 11: 357-375.

CRAWFORD, R.J.M., SHANNON, L.V. & D.E. POLLOCK, 1987. The Benguela ecosystem. 4. The major

fish and invertebrate resources. Oceanogr. Mar. Biol. Ann. Rev., 25: 353 - 505.

CROWTHER CAMPBELL & ASSOCIATES CC & CENTRE FOR MARINE STUDIES (CCA & CMS). 2001.

Generic Environmental Management Programme Reports for Oil and Gas Prospecting off the

Coast of South Africa. Prepared for Petroleum Agency SA, October 2001.

CRUIKSHANK, R.A., 1990. Anchovy distribution off Namibiadeduced from acoustic surveys with an

interpretation of migration by adults and recruits. S. Afr. J. Mar. Sci., 9: 53-68.

CRUM, L.A. & Y. MAO, 1996. Acoustically induced bubble growth at low frequencies and its

implication for human diver and marine mammal safety. J Acoust. Soc. Am., 99(5): 2898-

2907.

CSIR, 1996. Elizabeth Bay monitoring project: 1995 review. CSIR Report ENV/S-96066.

CSIR, 1998. Environmental Impact Assessment for the Proposed Exploration Drilling in Petroleum

Exploration Lease 17/18 on the Continental Shelf of KwaZulu-Natal, South Africa. CSIR

Report ENV/S-C 98045.

CSIR, 2009. Environmental Impact Assessment for the Proposed Desalination Project at Mile 6 Near

Swakopmund, Namibia, Draft EIR Report. Stellenbosch: CSIR.

CURRIE, H., GROBLER, K. & J. KEMPER (eds), 2009. Namibian Islands’ Marine Protected Area.

Ministry of Fisheries and Marine Resources, Namibia. http://www.nacoma.org.na/

key_Activities/Marine Protected Areas.htm.

DAHLHEIM, M.E. & D.K. LJUNGBLAD, 1990. Preliminary hearing study on gray whales (Eschrichtius

robustus) in the field. pp 335-346. In: Thomas, J.A. and Kastelin, R.A. (Eds.) Sensory

abilities of cetaceans, laboratory and field evidence. NATO ASI Series A: Life Sciences Vol.

196, Plenum Press, New York 710 pp.

DALEN, J. 1973. Stimulering av sildestimer. Forsøk i Hopavågen og Imsterfjorden/Verrafjorden 1973.

Rapport for NTNF. NTH, nr. 73-143-T, Trondheim. 36 s.

DALEN, J. & G.M. KNUTSEN, 1986. Scaring effects in fish and harmful effects on eggs. Larvae and

fry by offshore seismic explorations. P. 93-102 In: Merklinger, H.M. (ed.) Progress in

underwater acoustics. Plenum Press, London. 835pp

DALEN, J. & A. RAKNESS, 1985. Scaring effects on fish from 3D seismic surveys. Rep P.O. 8504.

Institute of Marine Research, Bergen Norway.

DALEN, J., ONA, E., VOLD SOLDAL, A. & R. SÆTRE, 1996. Seismiske undersøkeleser til havs: En

vurdering av konsekvenser for fisk og fiskerier. Fisken og Havet, 9: 1-26.

DAVID, J.H.M, 1989., Seals. In: Oceans of Life off Southern Africa, Eds. Payne, A.I.L. and Crawford,

R.J.M. Vlaeberg Publishers. Halfway House, South Africa.

DAVIS, R.W., EVANS, W.E. & B. WÜRSIG, 2000. Cetaceans, sea turtles and seabirds in the Northern

Gulf of Mexico: distribution, abundance and habitat associations. OCS Study MMS 2000-03,



US Dept of the Interior, Geological Survey, Biological Resources Division and Minerals

Management Service, Gulf of Mexico OCS Region, New Orleans, LA.

DAY, J.H., FIELD, J.G. & M. MONTGOMEREY. 1971. The use of numerical methods to determine the

distribution of the benthic fauna across the continental shelf of North Carolina. Journal of

Animal Ecology 40:93-126.

DE DECKER, A.H., 1970. Notes on an oxygen-depleted subsurface current off the west coast of

South Africa. Invest. Rep. Div. Sea Fish. South Africa, 84, 24 pp.

DESPREZ, M., 2000. Physical and biological impact of marine aggregate extraction along the French

coast of the Eastern English Channel: short-and long-term post-dredging restoration. ICES

Journal of Marine Science, 57: 1428–1438.

DFO, 2004. Potential impacts of seismic energy on snow crab. DFO Can. Sci. Advis. Sec. Habitat

Status Report 2004/003.

DI LORIO, L. & C.W. CLARKE, 2010. Exposure to seismic survey alters blue whale acoustic

communication, Biol. Lett., 6: 51-54.

DINGLE, R.V., 1973. The Geology of the Continental Shelf between Lüderitz (South West Africa) and

Cape Town with special reference to Tertiary Strata. J. Geol. Soc. Lond., 129: 337-263.

DRAKE, D.E., CACCHIONE, D.A. & H.A. KARL, 1985. Bottom currents and sediment transport on San

Pedro Shelf, California. J. Sed. Petr., 55: 15-28.

DUNCAN, P.M. 1985. Seismic sources in a marine environment. pp. 56-88 In : Proceedings of the

workshop on the effects of explosives use in the marine environment, Jan 29-31, 1985.

Tech. Rep. 5. Can. Oil and Gas Admin. Environ. Protection Branch, Ottawa, Canada. 398

pp.

DUNCOMBE RAE, C.M., 2005. A demonstration of the hydrographic partition of the Benguela

upwelling ecosystem at 26°40’S. Afr. J. mar. Sci., 27(3): 617–628.

DUNDEE, B.L., 2006. The diet and foraging ecology of chick-rearing gannets on the Namibian

islands in relation to environmental features: a study using telemetry. MSc thesis,

University of Cape Town, South Africa.

DUNLOP, R.A., NOAD, M.J., CATO, D.H. & D. STOKES, 2007. The social vocalization repertoire of

east Australian migrating humpback whales (Megaptera novaeangliae), Journal of the

Acoustical Society of America, 122: 2893-2905.

EKAU, W. & H. M. VERHEYE, 2005. Influence of oceanographic fronts and low oxygen on the

distribution of ichthyoplankton in the Benguela and southern Angola currents. Afr. J. mar.

Sci., 27(3): 629–639.

ELLINGSEN, K.E., 2002. Soft-sediment benthic biodiversity on the continental shelf in relation to

environmental variability. Marine Ecology Progress Series, 232: 15-27.

ELWEN, S.H., 2008. The distribution, movements and abundance of Heaviside’s dolphins in the

nearshore waters of the Western Cape, South Africa. Ph.D. dissertation, University of

Pretoria, Pretoria, South Africa. 211 pp.



ELWEN, S. & P.B. BEST, 2004. Environmental factors influencing the distribution of southern right

whales (Eubalaena australis) on the South Coast of South Africa I: Broad scale patterns.

Mar. Mammal Sci., 20 (3): 567-582.

ELWEN, S.H., GRIDLEY, T., ROUX, J.-P., BEST, P.B. & M.J. SMALE, 2013. Records of Kogiid whales in

Namibia, including the first record of the dwarf sperm whale (K. sima). Marine Biodiversity

Records. 6, e45 doi:10.1017/S1755267213000213.

ELWEN, S.H., BEST, P.B., REEB, D. & M. THORNTON, 2009. Near-shore diurnal movements and

behaviour of Heaviside’s dolphins (Cephalorhynchus heavisidii), with some comparative data

for dusky dolphins (Lagenorhynchus obscurus). South African Journal of Wildlife Research,

39(2): 143-154.

ELWEN, S.H., BEST, P.B., THORNTON, M., & D. REEB, 2010. Near-shore distribution of Heaviside's

(Cephalorhynchus heavisidii) and dusky dolphins (Lagenorhynchus obscurus) at the southern

limit of their range in South Africa. African Zoology, 45(1).

ELWEN, S.H. & R.H. LEENEY, 2011. Interactions between leatherback turtles and killer whales in

Namibian waters, including predation. South African Journal of Wildlife Research, 41(2):

205-209.

ELWEN, S.H. MEŸER, M.A.M, BEST, P.B., KOTZE, P.G.H, THORNTON, M. & S. SWANSON, 2006. Range

and movements of a nearshore delphinid, Heaviside's dolphin Cephalorhynchus heavisidii a

determined from satellite telemetry. Journal of Mammalogy, 87(5): 866–877.

ELWEN, S.H., REEB, D., THORNTON, M. & P.B. BEST, 2009. A population estimate of Heaviside's

dolphins Cephalorhynchus heavisidii in the southern end of their range. Marine Mammal

Science 25: 107-124.

ELWEN, S.H., SNYMAN, L. & R.H. LEENEY, 2010a. Report of the Nambian Dolphin Project 2010:

Ecology and consevation of coastal dolphins in Namibia. Submitted to the Ministry of

Fisheries and Marine Resources, Namibia. Pp. 1-36.

ELWEN, S.H., THORNTON, M., REEB, D. & P.B. BEST, 2010b. Near-shore distribution of Heaviside’s

(Cephalorhynchus heavisidii) and dusky dolphins (Lagenorhynchus obscurus) at the southern

limit of their range in South Africa. African Journal of Zoology 45: 78-91.

ELWEN, S.H., TONACHELLA, N., BARENDSE, J,. COLLINS, T.J.Q., BEST, P.B., ROSENBAUM, H.C.,

LEENEY, R.H. & T. GRIDLEY, 2014. Humpback whales in Namibia 2005-2012: occurrence,

seasonality and a regional comparison of photographic catalogues and scarring rates with

Gabon and West South Africa. Paper SC/65a/SH24 to the Scientific Committee of the

International Whaling Commission.

EMANUEL, B.P., BUSTAMANTE, R.H., BRANCH, G.M., EEKHOUT, S. & F.J. ODENDAAL, 1992. A

zoogeographic and functional approach to the selection of marine reserves on the west

coast of South Africa. S. Afr. J. Mar. Sci., 12: 341-354.

EMERY, J.M., MILLIMAN, J.D. & E. UCHUPI, 1973. Physical properties and suspended matter of

surface waters in the Southeastern Atlantic Ocean. J. Sed. Petr. 43: 822-837.

ENGÅS, A. & S. LØKKEBORG, 2002. Effects of seismic shooting and vessel-generated noise on fish

behaviour and catch rates. Bioacoustics, 12: 313-315.



ENGÅS, A., LØKKEBORG, S., ONA, E. & A.V. SODAL, 1996. Effects of seismic shooting on local

abundance and catch rates of cod (Gadus morhua) and haddock (Melanogrammus

aeglefinus). Can J. Fish. Aquat. Sci., 53(10): 2238-2249.

ENGER, P.S. 1981. Frequency discrimination in teleosts - Central or peripheral ? pp 243-255. In :

Tavolga, W.N., Popper, A.N. and Fay, R.R. (Eds.) Hearing and sound communication in

fishes. Springer-Verlag, New York. 608 pp.

ENVIRONMENTAL EVALUATION UNIT, 1996. Impacts of Deep Sea Diamond Mining, in the Atlantic 1

Mining Licence Area in Namibia, on the Natural Systems of the Marine Environment.

Environmental Evaluation Unit Report No. 11/96/158, University of Cape Town. Prepared

for De Beers Marine (Pty) Ltd. 370 pp.

ESCARAVAGE, V., HERMAN, P.M.J., MERCKX, B., WŁODARSKA-KOWALCZUK, M., AMOUROUX, J.M.,

DEGRAER, S., GRÉMARE, A., HEIP, C.H.R., HUMMEL, H., KARAKASSIS, I., LABRUNE, C. & W.

WILLEMS. 2009. Distribution patterns of macrofaunal species diversity in subtidal soft

sediments: biodiversity-productivity relationships from the MacroBen database. Marine

Ecology Progress Series 382: 253-264.

EVANS, D.L. & G.R. ENGLAND, 2001. Joint Interim Report Bahamas Marine Mammal Stranding Event

of 15-16 March 2000. U.S. Department of Commerce and U.S. Navy.

http://www.nmfs.noaa.gov/prot_res/overview/Interim_Bahamas_Report.pdf.

EVANS, P.G.H. & H. NICE, 1996. Review of the effects of underwater sound generated by seismic

surveys on cetaceans. Rep. from Sea Watch Foundation for UKOOA. 50 pp.

FALK, M.R. & M.J. LAWRENCE, 1973. Seismic exploration : its nature and effect on fish. Tech. Rep.

No. CENT/T-73-9. Resource Management Branch, Fisheries Operations Directorate, central

region Winnipeg. 51 pp.

FAO, 2008. International Guidelines for the Management of Deep-Sea Fisheries in the High Seas.

SPRFMO-VI-SWG-INF01

FAY, R.R., 1988. Hearing in vertebrates: a psychophysic databook. Hill-Fay associates, Winetka, IL.

FEGLEY, S.R., MACDONALD, B.A. & T.R. JACOBSEN, 1992. Short-term variation in the quantity and

quality of seston available to benthic suspension feeders. Estuar. Coast. Shelf Sci., 34: 393–

412.

FERNANDEZ, A., EDWARDS, J.F., RODRIGUEZ, F., ESPINOSA DE LOS MONEROS, A., HERRAEZ, P.,

CASTRO, P., JABER, J., et al., 2005. “‘Gas and Fat Embolic Syndrome’” Involving a Mass

Stranding of Beaked Whales ( Family Ziphiidae ) Exposed to Anthropogenic Sonar Signals.

Veterinary Pathology, 457: 446–457.

FINDLAY K.P., BEST P.B., ROSS G.J.B. and V.C. COCKROFT. 1992. The distribution of small

odontocete cetaceans off the coasts of South Africa and Namibia. S. Afr. J. Mar. Sci. 12:

237-270.

FINNERAN, J.J., SCHLUNDT, C.E., CARDER, D.A., CLARK, J.A., YOUNG, J.A., GASPIN, J.B. & S.H.

RIDGWAY, 2000. Auditory and behavioural responses of bottlenose dolphins (Tursiops

truncatus) and a beluga whale (Delphinapterus leucas) to impulsive sounds resembling

distant signatures of underwater explosions. J. Acoust. Soc. Am., 108(1): 417–431.



FINNERAN, J.J., CARDER, D.A. & S.H. RIDGWAY, 2001. Temporary threshold shift (TTS) in

bottlenose dolphins (Tursiops truncatus) exposed to tonal signals, J. Acoust. Soc. Am.

110(5), 2749(A), 142nd Meeting of the Acoustical Society of America, Fort Lauderdale, FL,

December 2001.

FINNERAN, J.J., CARDER, D.A. & S.H. RIDGWAY, 2003. Temporary threshold shift (TTS)

measurements in bottlenose dolphins (Tursiops truncatus), belugas (Delphinapterus

leucas), and California sea lions (Zalophus califomianus), Environmental Consequences of

Underwater Sound (ECOUS) Symposium, San Antonio, TX, 12-16 May 2003.

FINNERAN, J.J., SCHLUNDT, C.E., DEAR, R., CARDER, D.A. & S.H. RIDGWAY, 2002. Temporary shift

in masked hearing thresholds (MTTS) in odontocetes after exposure to single underwater

impulses from a seismic watergun, J. Acoust. Soc. Am. 111: 2929-2940.

FLACH, E. & L. THOMSEN, 1998. Do physical and chemical factors structure the macrobenthic

community at a continental slope in the NE Atlantic? Hydrobiologia, 375/376: 265-285.

FLEISCHER, G., 1976. Hearing in extinct cetaceans as determined by cochlear structure. J

Paleontol., 50 (1): 133-52.

FLEISCHER, G., 1978. Evolutionary principles of the mammalian ear. Advances in anatomy,

embryology and cell biology. 55(5): 1-70, Springer-Verlag, Berlin.

FOBES, J.L. & C.C. SMOCK, 1981. Sensory capabilities of marine mammals. Psychol. Bull., 89(2):

288-307.

FOSSING, H., FERDELMAN, T.G. & P. BERG, 2000. Sulfate reduction and methane oxidation in

continental margin sediments influenced by irrigation (South-East Atlantic off Namibia).

Geochim. Cosmochim. Acta. 64(5): 897–910.

FRANTZIS. A., 1998. Does acoustic testing strand whales? Nature, 392 (6671): 29.

GEDAMKE, J., GALES, N. & S. FRYDMAN, 2011. Assessing risk of baleen whale hearing loss from

seismic surveys: The effect of uncertainty and individual variation, The Journal of the

Acoustical Society of America, 129: 496-506.

GOOLD, J.C. & P.J. FISH, 1998. Broadband spectra of seismic survey air-gun emissions, with

reference to dolphin auditory thresholds. J. Acoust. Soc. Am., 103 (4): 2177- 2184.

GOOSEN, A.J.J., GIBBONS, M.J., MCMILLAN, I.K., DALE, D.C. & P.A. WICKENS, 2000. Benthic

biological study of the Marshall Fork and Elephant Basin areas off Lüderitz. Prepared by De

Beers Marine (Pty) Ltd. for Diamond Fields Namibia, January 2000. 62 pp.

GORDON, J.C., GILLESPIE, D., POTTER, J.R., FRANTZIS, A., SIMMONDS, M.P., SWIFT, R. & D.

THOMPSON, 2004. A review of the Effects of Seismic Surveys on Marine Mammals. Marine

Technology Society Journal, 37: 16-34.

GORDON, J. & A. MOSCROP, 1996. Underwater noise pollution and its significance for whales and

dolphins. pp 281-319 In Simmonds. M.P. and Hutchinson, J.D. (eds.) The conservation of

whales and dolphins. John Wiley and Sons, London.

GRAY, J.S., 1974. Animal-sediment relationships. Oceanography and Marine Biology Annual Reviews

12: 223-261.



GRAY, J.S., 1981. The ecology of marine sediments: an introduction to the structure and function

of benthic communities. Cambridge University Press, Cambridge.

GREENLAW, C.F., 1987. Psychoacoustics and pinnipeds. In MATE, B.R. and HARVEY, J.T. (Eds.)

Acoustic deterrents in marine mammal conflicts with fisheries. US National Technical

Information Service, Springfield VA. 116 pp NTIS PB-178439.

GUERRA, A., A.F. GONZÁLEZ, F. ROCHA, J. GRACIA & M. VERRHIONE. 2004. Calamares gigantes

varados: victimas de exploraciones acústicas. Investigacion y Ciencia 2004: 35-37.

HALL, J.D. & C.S. JOHNSON, 1972. Auditory thresholds of a killer whale (Orcinus orca) Linnaeus. J

Acoust. Soc. Am., 52(2): 515-517.

HAMPTON, I., 1992. The role of acoustic surveys in the assessment of pelagic fish resources on the

South African continental shelf. South African Journal of Marine Science, 12: 1031-1050.

HAMPTON, I., 2003. Harvesting the Sea. In: MOLLOY, F. & T. REINIKAINEN (Eds), 2003. Namibia`s

Marine Environment. Directorate of Environmental Affairs, Ministry of Environment &

Tourism, Namibia, 31-69.

HAMPTON, I., BOYER, D.C., PENNEY, A.J., PEREIRA, A.F. & M. SARDINHA, 1999. BCLME Thematic

Report 1: Integrated Overview of Fisheries of the Benguela Current Region. Unpublished

Report, 89pp.

HANEY, J.C., HAURY, L.R., MULLINEAUX, L.S. & C.L. FEY, 1995. Sea-bird aggregation at a deep

North Pacific seamount. Marine Biology, 123: 1-9.

HANLON, R.H. & B.U. BUDELMANN, 1987. Why cephalopods are probably not “deaf”. American

Naturalist 129: 312–17.

HANSEN. F.C., CLOETE. R.R. & H.M. VERHEYE, 2005. Seasonal and spatial variability of dominant

copepods along a transect off Walvis Bay (23ºS), Namibia. African Journal of Marine

Science, 27: 55-63.

HARRIS, R. E., MILLER, G.W. & W.E. RICHARDSON, 2001. Seal responses to airgun sounds during

summer seismic surveys in the Alaskan Beaufort Sea. Mar. Mamm. Sci., 17(4): 795-812.

HASSEL, A., KNUTSEN, T., DALEN, J., SKAAR, K., LØKKEBORG, S., MISUND, O.A., ØSTENSEN, Ø.,

FONN, M. & E.K. HAUGLAND, 2004. Influence of seismic shooting on the lesser sandeel

(Ammodytes marinus). ICES J. Mar. Sci., 61: 1165-1173.

HASTINGS, M.C., POPPER, A.N., FINNERAN, J.J. & P.J. LANFORD, 1996. Effect of low frequency

underwater sound on hair cells of the inner ear and lateral line of the teleost fish

Astronotus ocellatus. J. Acoust. Soc. Am., 99: 1759-1766.

HAWKINS, A.D., 1973. The sensitivity of fish to sounds. Oceanogr. Mar. Biol. Ann. Rev., 11: 291-

340.

HAWKINS, A.D. & A.A. MYRBERG, 1983. Hearing and sound communication under water. pp 347-405

In: Bioacoustics a comparative approach. Lewis, B. (ed.). Academic Press, Sydney 491 pp.

HAYS, G.C. HOUGHTON, J.D.R., ISAACS, C. KING, R.S. LLOYD, C. & P. LOVELL, 2004. First records

of oceanic dive profiles for leatherback turtles, Dermochelys coriacea, indicate behavioural

plasticity associated with long-distance migration. Animal Behaviour, 67: 733-743.



HOLLIDAY, D.V., PIEPER, R.E., CLARKE, M.E. & C.F. GREENLAW, 1987. Effects of airgun energy

releases on the northern anchovy. API Publ. No 4453, American Petr. Inst. Health and

Environmental Sciences Dept., Washington DC. 108pp.

HOLTZHAUZEN, J.A., 2000. Population dynamics and life history of westcoast steenbras

Lithognathus aureti (Sparidae), and management options for the sustainable exploitation of

the steenbras resource in Namibian waters. PhD Thesis, University of Port Elizabeth: 233

pages.

HOLTZHAUSEN, J.A., KIRCHNER, C.H. & S.F. VOGES, 2001. Observations on the linefish resources of

Namibia, 1999-2000, with special reference to West Coast steenbras and silver kob. South

African Journal of Marine Science 23: 135-144.

HORRIDGE, G.A., 1965. Non-motile sensory cilia and neuromuscular junctions in a ctenophore

independent effector organ. Proc. R. Soc. Lond. B, 162: 333-350.

HORRIDGE, G.A., 1966. Some recently discovered underwater vibration receptors in invertebrates.

In: BARNES, H. (Ed). Some contemporary studies in marine science. Allen and Unwin,

London. Pp. 395-405.

HORRIDGE, G.A. & P.S. BOULTON, 1967. Prey detection by chaetognaths via a vibration sense.

Proc. R. Soc. Lond. B, 168: 413-419.

HOVLAND, M., VASSHUS, S., INDREEIDE, A., AUSTDAL, L. & Ø. NILSEN, 2002. Mapping and imaging

deep-sea coral reefs off Norway, 1982-2000. Hydrobiol. 471: 13-17.

HOWARD, J.A.E., JARRE, A., CLARK, A.E. & C.L. MOLONEY, 2007. Application of the sequential t-

test algorithm or analyzing regime shifts to the southern Benguela ecosystem. African

Journal of Marine Science 29(3): 437-451.

HU, M.Y., YAN, H.Y., CHUNG, W., et al. 2009. Acoustically evoked potentials in two cephalopods

inferred using the auditory brainstem response (ABR) approach. Comp. Biochem. Phys. A

153: 278–84.

HUGHES, G.R. 1974. The Sea Turtles of South East Africa I. Status, morphology and distributions.

Investl. Rep. Oceanogr. Res. Inst. 35.

HUI, C,A., 1985. Undersea topography and the comparative distributions of two pelagic cetaceans.

Fishery Bulletin, 83(3): 472-475.

HUTCHINGS L., NELSON G., HORSTMANN D.A. & R. TARR, 1983. Interactions between coastal

plankton and sand mussels along the Cape coast, South Africa. In: Sandy Beaches as

Ecosystems. Mclachlan A and T E Erasmus (eds). Junk, The Hague. pp 481-500.

IUCN, 2011. IUCN Red List of Threatened Species. Version 2011.2. www.iucnredlist.org.

Downloaded on 5 June 2012.

IWC, 2012. Report of the Scientific Committee. Annex H: Other Southern Hemisphere Whale Stocks

Committee 11–23.

JACKSON, L.F. & S. McGIBBON, 1991. Human activities and factors affecting the distribution of

macro-benthic fauna in Saldanha Bay. S. Afr. J. Aquat. Sci., 17: 89-102.

JACOBS, D.W. & J.D. HALL, 1972. Auditory thresholds of a freshwater dolphin, Inia geoffrensis

Blaineville. J. Acoust. Soc. Am., 51(2,pt2): 530-533.



JEPSON, P.D., ARBELO, M., DEAVILLE,R., PATTERSON, I.A.P., CASTRO, P., BAKER, J.R., DEGOLLADA,

E., ROSS, H.M., HERRÁEZ, P., POCKNELL, A.M., RODRÍGUEZ, F., HOWIE, F.E., ESPINOSA, A.,

REID, R.J., JABER, J.R., MARTIN, V., CUNNINGHAM, A.A. & A. FERNÁNDEZ, 2003. Gas–

bubble lesions in stranded cetaceans. Nature, 425: 575.

JOHNSON, C.S., 1967. Sound detection thresholds in marine mammals. pp. 247-260. In: Tavolga,

W.N. (ed.) Marine bioacoustics, Vol. 2. Pergammon, Oxford, U.K. 353 pp.

JOHNSON, C.S., 1986. Masked tonal thresholds in the bottlenosed porpoise. J. Acoust. Soc. Am.,

44(4): 965-967.

JOINT NATURE CONSERVATION COMMITTEE (JNCC), 2010. JNCC guidelines for minimising the risk of

disturbance and injury to marine mammals from seismic surveys. August 2010

KAIFU, K., AKAMATSU, T. & S. SEGAWA, 2008. Underwater sound detection by cephalopod

statocyst. Fisheries Sci. 74: 781–86.

KASTAK, D., SCHUSTERMAN, R.J., SOUTHALL, B.L. & C.J. REICHMUTH, 1999. ‘‘Underwater

temporary threshold shift in three species of pinniped,’’ J. Acoust. Soc. Am., 106: 1142–

1148.

KENDALL, M.A. & S. WIDDICOMBE, 1999. Small scale patterns in the structure of macrofaunal

assemblages of shallow soft sediments. Journal of Experimental Marine Biology & Ecology,

237:127-140.

KENNY, A. J., REES, H. L., GREENING, J., & S. CAMPBELL, 1998. The effects of marine gravel

extraction on the macrobenthos at an experimental dredge site off north Norfolk, U.K.

(Results 3 years post-dredging). ICES CM 1998/V:14, pp. 1-8.

KENSLEY, B., 1980. Decapod and Isopod Crustaceans From the West Coast of Southern Africa,

Including Seamounts Vema and Tripp. Annals of the South African Museum, 83(2): 13-32.

KENSLEY, B., 1981. On the Zoogeography of Southern African Decapod Crustacea, With a

Distributional Checklist. Smithsonian Contributions to Zoology, 338: 1-64.

KETOS ECOLOGY, 2009. 'Turtle Guards': A method to reduce the marine turtle mortality occurring

in certain seismic survey equipment. www.ketosecology.co.uk.

KETTEN, D.R., LIEN, J. & S. TODD, 1993. Blast injury in humpback whale ears: evidence and

implications. J. Acoust. Soc. Am., 94(3 Pt 2): 1849-1850.

KINOSHITA, I. & S. FUJITA, 1988. Larvae and juveniles of blue drum, Nibea mitsukurii, occurring in

the surf zone of Tosa Bay, Japan. Japanese Journal of Ichthyology, 35: 25-30.

KIRCHNER, C.H., 2001. Fisheries regulations based on yield per recruit analysis for the linefish

silver kob Argyrosomus inodorus in Namibian waters. Fisheries Research, 52: 155–167.

KIRCHNER, C.H., HOLTZHAUSEN, J.A. & S.F. VOGES, 2001. Introducing size limits as a management

tool for the recreational linefishery of silver kob, Argyrosomus inodorus (Griffiths and

Heemstra), in Namibian waters Fisheries Management and Ecology 8: 227-237.

KIRCHNER, C.H., SAKKO, A. & J.I. BARNES, 2000. Estimation of the economic value of the Namibian

recreational rock-and-surf fishery. South African Journal of Marine Science 22: 17-25.



KIRKMAN, S.P., OOSTHUIZEN, W.H., MEŸER, M.A., KOTZE, P.G.H., ROUX, J.-P. & L.G. UNDERHILL,

2007. Making sense out of censuses and dealing with missing data: trends in pup counts of

Cape Fur Seals between 1972–2004. African Journal of Marine Science 29(2): 161–176.

KIRKMAN, S.P., YEMANE, D., OOSTHUIZEN, W.H., MEYER, M.A., KOTZE, P.G.H, SKRYPZECK, H., VAZ

VELHO, F. & L.G. UNDERHILL, 2012. Spatio-temporal shifts of the dynamic Cape fur seal

population in southern Africa, based on aerial censuses (1972–2009). Marine mammal

Science, doi: 10.1111/j.1748-7692.2012.00584.x

KOLSKI, W.R. & S.R. JOHNSON, 1987. Behavioral studies and aerial photogrammetry. Sect. 4 In :

Responses of bowhead whales to an offshore drilling operation in the Alaskan Beaufort Sea,

autumn 1986. Rep. from LGL Ltd., King City, Ont., for Dep. Indian Affairs & Northern Dev.,

Hull, Que. 150 p.

KOSHELEVA, V., 1992. The impact of air guns used in marine seismic explorations on organisms

living in the Barents Sea. Contr. Petro Piscis II `92 Conference F-5, Bergen, 6-8 April, 1992.

6p.

KOSLOW, J.A., 1996. Energetic and life history patterns of deep-sea benthic, benthopelagic and

seamount associated fish. Journal of Fish Biology, 49A: 54-74.

KOSTYUCHENKO, L.P., 1971. Effects of elastic waves generated in marine seismic prospecting of

fish eggs in the Black Sea. Hydrobiol. J., 9 (5): 45-48.

LACROIX, D. L., R. B. LANCTOT, J. A. REED & T. L. MCDONALD, 2003. Effect of underwater seismic

surveys on molting male Long-tailed Ducks in the Beaufort Sea, Alaska. Canadian Journal of

Zoology 81(11): 1862-1875.

LAIST, D.W., KNOWLTON, A.R., MEAD, J.G., COLLET, A.S. & M. PODESTA, 2001. Collisions between

ships and whales. Marine Mammal Science 17(1): 35-75.

LAMBARDI, P., LUTJEHARMS, J.R.E., MENACCI, R., HAYS, G.C. & P. LUSCHI, 2008. Influence of

ocean currents on long-distance movement of leatherback sea turtles in the Southwest

Indian Ocean. Marine Ecology Progress Series, 353: 289–301.

LAMMERS, M.O., AU, W.W.L. & D.L. HERZING, 2003. The broadband social acoustic signaling

behavior of spinner and spotted dolphins, Journal of the Acoustical Society of America,

114: 1629-1639.

LANE, S.B. & R.A. CARTER, 1999. Generic Environmental Management Programme for Marine

Diamond MIning off the West Coast of South Africa. Marine Diamond Mines Association,

Cape Town, South Africa. 6 Volumes.

LANGE, L., 2012. Use of demersal bycatch data to determine the distribution of soft-bottom

assemblages off the West and South Coasts of South Africa. PhD thesis, University of Cape

Town.

LE ROUX, L., 1998. Research on Deepsea Red Crab after more than 20 years of Exploitation.

Namibia Brief, 20: 126-128.

LEENEY, R.H., POST, K., HAZEVOET, C.J. AND S.H. ELWEN, 2013. Pygmy right whale records from

Namibia. African Journal of Marine Science 35(1): 133-139.



LENHARDT, M.L., BELLMUND, S., BYLES, R.A., HARKINS, S.W. & J.A. MUSICK, 1983. Marine turtle

reception of bone conducted sound. J. Aud. Res., 23: 119-125.

LETT, C., VEITCH, J., VAN DER LINGEN, C.D. & L. HUTCHINGS, 2007. Assessment of an

environmental barrier to transport of ichthyoplankton from the southern to the northern

Benguela ecosystems. Mar.Ecol. Prog. Ser., 347: 247–259.

LEUNG-NG, S. & S. LEUNG, 2003. Behavioral response of Indo-Pacific humpback dolphin (Sousa

chinensis) to vessel traffic. Mar. Env. Res., 56: 555-567.

LEVIN, L.A., 2003. Oxygen minimum zone benthos: adaptation and community response to hypoxia.

Oceanography and Marine Biology: an Annual Review 41: 1-45.

LEVIN, L.A., WHITCRAFT, C.R., MENDOZA, G.F., GONZALEZ, J.P. & G. COWIE, 2009. Oxygen and

organic matter thresholds for benthic faunal activity on the Pakistan margin oxygen

minimum zone (700 - 1100 m). Deep-Sea Reserach II 56: 449-471.

LEWIS, B., 1983. Bioacoustics - a comparative approach. Academic Press, Sydney 491 pp.

LIEN, J., TODD, S. STEVICK, P., MARQUES, F. & D. KETTEN, 1993. The reaction of humpback whales

to underwater explosions: orientation, movements and behaviour. J. Acoust. Soc. Am.,

94(3, Pt. 2): 1849.

LIPINSKI, M.R., 1992. Cephalopods and the Benguela ecosystem: trophic relationships and impacts.

S. Afr. J. Mar. Sci., 12 : 791-802.

LJUNGBLAD, D.K., WURSIG, B., SWARTZ, S.L. & J.M. KEENE, 1988. Observations on the behavioural

responses of bowhead whales (Balaena mysticetus) to active geophysical vessels in the

Alaskan Beaufort Sea. Arctic, 41(3): 183-194.

LØKKEBORG, S., 1991. Effects of a geophysical survey on catching success in longline fishing ICES

CM. 40: 1-9.

LØKKEBORG S. & A.V. SOLDAL, 1993. The influence of seismic exploration with airguns on cod

(Gadus morhua) behaviour and catch rates. ICES mar. Sci Symp., 196: 62-67.

LOMBARD, A.T., STRAUSS, T., HARRIS, J., SINK, K., ATTWOOD, C. & HUTCHINGS, L. (2004) National

Spatial Biodiversity Assessment 2004: South African Technical Report Volume 4: Marine

Component

LOMBARTE, A.,YAN, H.Y, POPPER, A.N., CHANG, J.C. & C. PLATT 1993. Damage and regeneration of

hair cell ciliary bundles in a fish ear following treatment with gentamicin. Hearing

Research, 66:166-174.

LONGHURST, A. R., 2006. Ecological Geography of the Sea. 2nd edition. Academic Press, San Diego.

pp. 560.

LUDYNIA, K., 2007. Identification and characterisation of foraging areas of seabirds in upwelling

systems: biological and hydrographic implications for foraging at sea. PhD thesis, University

of Kiel, Germany.

LUKE, K., SEIBERT, U., LEPPER, P.A. & M.A. BLANCHET, 2009. Temporary shift in masked hearing

thresholds in a harbor porpoise (Phocoena phocoena) after exposure to seismic airgun

stimuli, Journal of the Acoustical Society of America, 125: 4060-4070.



MAARTENS, L., 2003. Biodiversity. In: MOLLOY, F. & T. REINIKAINEN (Eds). Namibia’s Marine

Environment. Directorate of Environmental Affairs, Ministry of Environment and Tourism,

Namibia: 103-135.

MacISSAC, K., BOURBONNAIS, C., KENCHINGTON, E.D., GORDON JR. & S. GASS, 2001. Observations

on the occurrence and habitat preference of corals in Atlantic Canada. In: (eds.) J.H.M.

WILLISON, J. HALL, S.E. GASS, E.L.R. KENCHINGTON, M. BUTLER, AND P. DOHERTY.

Proceedings of the First International Symposium on Deep-Sea Corals. Ecology Action Centre

and Nova Scotia Museum, Halifax, Nova Scotia.

MacLEOD, C.D. & A. D’AMICO, 2006. A review of beaked whale behaviour and ecology in relation to

assessing and mitigating impacts of anthropogenic noise. Journal of Cetacean Research and

Management 7(3): 211–221.

MacPHERSON, E. & A. GORDOA, 1992. Trends in the demersal fish community off Namibia from 1983

to 1990. South African Journal of Marine Science 12: 635-649.

MADSEN, P.T., CARDER, D.A., AU, W.W.L., NACHTIGALL, P.E., MOHL, B. & S. RIDGWAY, 2003.

Sound production in sperm whale (L), Jounal of the Acoustical Society of America, 113:

2988.

MADSEN, P.T., CARDER, D.A., BEDHOLM, K. & S.H. RIDGWAY, 2005a. Porpoise clicks from a sperm

whale nose - Convergent evolution of 130 kHz pulses in toothed whale sonars?, Bioacoustics,

15: 195-206.

MADSEN, P.T., JOHNSON, M., DE SOTO, N.A., ZIMMER, W.M.X. & P. TYACK, 2005b. Biosonar

performance of foraging beaked whales (Mesoplodon densirostris), Journal Of Experimental

Biology, 208: 181-194.

MADSEN, P.T., JOHNSON, M., MILLER, P.J.O., AGUILAR SOTO, N., LYNCH, J. & P. TYACK, 2006.

Quantative measures of air gun pulses recorded on sperm whales (Physeter macrocephalus)

using acoustic tags during controlled exposure experiments. J. Acoust. Soc. Am.

MADSEN, P.T., MØHL, B., NIELSEN, K. & M. WAHLBERG, 2002. Male sperm whale behaviour during

exposures to distant seismic survey pulses. Aquatic Mammals 28: 231–240.

MADSEN, P.T., WAHLBERG, M. & B. MOHL, 2002. Male sperm whale (Physeter macrocephalus)

acoustics in a high-latitude habitat: implications for echolocation and communication,

Behav. Ecol. Sociobiol., 53: 31-41.

MALME , C.I. MILES, P.R., CLARK, C.W., TYACK, P. & J.E. BIRD, 1983. Investigations of the potential

effects of underwater noise from petroleum industry activities on migrating gray whale

behaviour. BBN Rep. 5366. Rep. from Bolt Beranek and Newman Inc., Cambridge, MA, for

U.S. Minerals Manage. Serv. Anchorage, AK, USA.

MALME , C.I. MILES, P.R., CLARK, C.W., TYACK, P. & J.E. BIRD, 1984. Investigations of the potential

effects of underwater noise from petroleum industry activities on migrating gray whale

behaviour. Phase II: January 1984 migration. BBN Rep. 5586. Rep. from Bolt Beranek and

Newman Inc., Cambridge, MA, for U.S. Minerals Manage. Serv. Anchorage, AK, USA.

MALME, C.I., MILES, P.R., TYACK, P., CLARK, C.W. & J.E. BIRD, 1985. Investigation of the potential

effects of underwater noise from petroleum industry activities on feeding humpback whale

behavior. BBN Report 5851, OCS Study MMS 85-0019. Report from BBN Laboratories Inc.,



Cambridge, MA, for U.S. Minerals Management Service, NTIS PB86-218385. Bolt, Beranek,

and Newman, Anchorage, AK.

MALME, C. I., WURSIG, B., BIRD, J.E. & P. TYACK, 1986. Behavioural responses of gray whales to

industrial noise: Feeding observations and predictive modelling. BBN Rep 6265. Outer Cont.

Shelf Environ. Assess. Progr., Final Rep. Princ. Invest., NOAA, Anchorage AK, USA.

MANIWA, Y., 1976. Attraction of bony fish, squid and crab by sound. Pp 271-283. In: SCHUIJF, A.

and HAWKINS, A.D. (Eds.) Sound reception in fish. Elsevier, New York.

MANN, D.A., HIGGS, D.M., TAVOLGA, W.N., SOUZA, M.J. & A.N. POPPER, 2001. Ultrasound

detection by clupeiform fishes. J. Acoust. Soc. Am., 109: 3048-3054.

MATE, B.R., BEST, P.B., LAGERQUIST, B.A. & , M.H. WINSOR, 2011. Coastal, offshore and migratory

movements of South African right whales revealed by satellite telemetry. Marine Mammal

Science, 27(3): 455-476.

MATE, B.R., LAGERQUIST, B.A., WINDSOR, M., GERACI, J. & J.H. PRESCOTT, 2005. Movements and

dive habits of a satellite-monitoring longfinned pilot whales (Globicephala melas) in the

northwet Atlantic. Marine Mammal Science 21(10): 136-144.

MATISHOV, G.G., 1992. The reaction of bottom-fish larvae to airgun pulses in the context of the

vulnerable Barents Sea ecosystem. Contr. Petro Piscis II ‘92 F-5, Bergen, Norway, 6-8 April,

1992. 2pp.

MATTHEWS, S.G. & G.C. PITCHER, 1996. Worst recorded marine mortality on the South African

coast. In: YASUMOTO, T, OSHIMA, Y. & Y. FUKUYO (Eds), Harmful and Toxic Algal Blooms.

Intergovernmental Oceanographic Commission of UNESCO, pp 89-92.

McCAULEY, R.D. 1994. Seismic surveys. In: Swan, J.M., Neff, J.M., Young, P.C. (Eds.).

Environmental implications of offshore oil and gas development in Australia - The findings of

an Independent Scientific Review. APEA, Sydney, Australia, 695 pp.

McCAULEY, R.D., CATO, D.H. & A.F. JEFFREY, 1996. A study on the impacts of vessel noise on

humpback whales in Hervey Bay. Rep from Department of Marine Biology, James Cook

University, Townsville, Australia to Department of Environment and Heritage, Qld,

Australia. 137 pp.

McCAULEY, R.D., FEWTRELL, J., DUNCAN, A.J., JENNER, C., JENNER, M-N, PENROSE, J.D., PRINCE,

R.I.T., ADHITYA, A., MURDOCH, J. & K. MCCABE, 2000. Marine seismic surveys: Analysis and

propagation of air-gun signals; and effects of air-gun exposure on humpback whales, sea

turtles, fishes and squid. Report produced for the Australian Petroleum Production

Exploration Association. 198 pp.

McCAULEY, R.D., FEWTRELL J. & A.N. POPPER, 2003. High intensity anthropogenic sound damages

fish ears. J. Acoust. Soc. Am., 113: 638-642.

McDONALD, M.A., HILDEBRAND, J.A. & S.C. WEBB, 1995. Blue and fin whales observed on a seafloor

array in the Northeast Pacific. J. Acoust. Soc. Am., 98(2,pt1): 712-721.

McDONALD, M.A., HILDEBRAND, J.A., WEBB, S., DORMAN, L. & C.G. FOX, 1993. Vocalisations of

blue and fin whales during a mid-ocean airgun experiment. J. Acoust. Soc. Am., 94(3, Pt.

2): 1894.



McLACHLAN, A., 1980. The definition of sandy beaches in relation to exposure: a simple rating

system. S. Afr. J. Sci., 76: 137-138.

MELCÓN, M.L., CIMMINS, A.J., KEROSKY, S.M., ROCHE, L.K., WIGGINS, S.M. & J.A. HILDERBRAND,

2012. Blue whales respond to anthropogenic noise, PLoS One, 7: e32681.

MITCHELL-INNES, B.A. and D.R. WALKER. 1991. Short-term variability during an Anchor Station study

in the southern Benguela upwelling system. Phytoplankton production and biomass in

relation to species changes. Prog. Oceanogr., 28: 65-89.

MOEIN, S.E., MUSICK, J.A., KEINATH, J.A., BARNARD, D.E., LENHARDT, M. & R. GEORGE, 1994.

Evaluation of seismic sources for repelling sea turtles from hopper dredges. Report for US

Army Corps of Engineers, from Virginia Institute of Marine Science, VA USA.

MOEIN-BARTOL, S., J.A. MUSICK & M.L. LENHARDT, 1999. Auditory evoked potentials of the

loggerhead sea turtle (Caretta caretta). Copeia, 1999: 836-840.

MOLDAN, A.G.S., 1978. A study of the effects of dredging on the benthic macrofauna in Saldanha

Bay. South African Journal of Science, 74: 106-108.

MONTEIRO, P.M.S. & A.K. VAN DER PLAS, 2006. Low Oxygen Water (LOW) variability in the Benguela

System: Key processes and forcing scales relevant to forecasting. In: SHANNON, V.,

HEMPEL, G., MALANOTTE-RIZZOLI, P., MOLONEY, C. & J. WOODS (Eds). Large Marine

Ecosystems, Vol. 15, pp 91-109.

MOONEY, A.T., HANLON, R.T., CHRISTENSEN-DALSGAARD, J., et al., 2010. Sound detection by the

longfin squid (Loligo pealei) studied with auditory evoked potentials: sensitivity to low-

frequency particle motion and not pressure. J. Exp. Biol., 213: 3748–59.

MOORE, A. & J.L.S. COBB, 1986. Neurophysiological studies on the detection of mechanical stimuli

in Ophiura ophiura. J. Exp. Mar. Biol. Ecol. 104: 125-141.

MOORE, P.W.B. & R.J. SCHUSTERMAN, 1987. Audiometric responses of northern fur seals,

Callorhinus ursinus. Mar. Mamm. Sci., 3(1): 31 - 53.

MORANT, P.D., 2006. Environmental Management Programme Report for Exploration/Appraisal

Drilling in the Kudu Gas Production Licence No 001 on the Continental Shelf of Namibia.

Prepared for Energy Africa Kudu Limited. CSIR Report CSIR/NRE/ECO/2006/0085/C.

MORISAKA, T., KARCZMARSKI, L., AKAMATSU, T., SAKAI, M., DAWSON, S. & M. THORNTON, 2011.

Echolocation signals of Heaviside’s dolphins (Cephalorhynchus heavisidii), Journal of the

Acoustical Society of America 129: 449-457.

MUSSOLINE, S.E., RISCH, D., HATCH, L.T., WEINRICH, M.T., WILEY, D.N., THOMPSON, M.A.,

CORKERON, P.J. & S.M. VAN PARIJS, 2012. Seasonal and diel variation in North Atlantic

right whale up-calls: implications for management and conservation in the northwestern

Atlantic Ocean, Endangered Species Research 17: 17-26.

NACHTIGALL, P.E, AU, W.W.L., PALOWSKI, J.L. & P.W.B. MOORE, 1995. Risso’s dolphin (Grampus

griseus) hearing thresholds in Kaneohe Bay, Hawaii. In: Kastelin, R.A., Thomas, J.A., and

Nachtigall, P.E. (Eds.). Sensory systems of aquatic mammals. De Spil Publ. Woerden,

Netherlands.



NACHTIGALL, P.E., AU, W.W.L. & J. PALOWSKII, 1996. Low frequency hearing in three species of

odontocete. J. Acoust. Soc. Am., 100(4;pt2): 2611.

NELSON G. & L. HUTCHINGS, 1983. The Benguela upwelling area. Prog. Oceanogr., 12: 333-356.

NEWMAN, G.G. & D.E. POLLOCK, 1971. Biology and migration of rock lobster Jasus lalandii and

their effect on availability at Elands Bay, South Africa. Investl. Rep. Div. Sea Fish. S. Afr.,

94: 1-24.

NIEUKIRK, S.L., MELLINGER, D.K. et al., 2012. Sounds from airguns and fin whales recorded in the

mid-Atlantic Ocean, 1999--2009. The Journal of the Acoustical Society of America 131(2):

1102-1112.

NORRIS, J.C. & S. LEATHERWOOD, 1981. Hearing in the bowhead whale, Balaena mysticetus, as

estimated from cochlear morphology. Pp 745-787. In: Albert, T.F. (ed.). Tissue structural

studies and other investigations on the biology of endangered whales in the Beaufort Sea,

Vol. II. Rep. from Dept. Vet. Sci., Univ. Maryland, College Park, MD, for US Bur. Land

manage., Anchorage, AK. 953 pp (2 vol.) NTIS PB86-153566.

NOWACEK, D.P., THORNE, L.H., JOHNSTON, D.W. & P.L. TYACK, 2007. Responses of cetaceans to

anthropogenic noise. Mammal Rev., 37(2): 81-115.

NRC, 2003. Ocean noise and marine mammals. National Academy Press, Washington, DC.

NRC, 2005. Marine mammal populations and ocean noise, determining when noise causes

biologically significant effects. The National Academy Press, Washington, DC.

OFFUT, G.C., 1970. Acoustic stimulus perception by the American lobster Homarus americanus

(Decapoda). Experentia, 26: 1276-1278.

O'HARA, J., 1990. Avoidance responses of loggerhead turtles, Caretta caretta, to low frequency

sound. Copeia, 1990(2): 564-567.

O’HARA, J. & J.R. WILCOX, 1990. Avoidance responses of loggerhead turtles, Caretta caretta, to

low frequency sound. Copeia, 1990: 564-567.

OOSTHUIZEN W.H., 1991. General movements of South African (Cape) fur seals Arctocephalus

pusillus pusillus from analysis of recoveries of tagged animals. S. Afr. J. Mar. Sci., 11: 21-

30.

PACKARD, A., KARLSEN, H.E. & O. SAND, 1990. Low frequency hearing in cephalopods. J. Comp.

Physiol., 166: 501-505.

PARENTE, C.L., LONTRA. J.D. & M.E. ARAÚJO, 2006. Ocurrence of sea turtles during seismic surveys

in northeastern Brazil. Biota Neotrop., 6(1), www.biotaneotropica.org.br/

v6n1/pt/abstract?article+bn00306012006. ISSN 1676-0611

PARKINS, C.A. & J. G. FIELD, 1997. A baseline study of the benthic communities of the unmined

sediments of the De Beers Marine SASA Grid. Unpublished Report to De Beers Marine,

October 1997, pp 29.

PARKINS, C.A. & J.G.FIELD, 1998. The effects of deep sea diamond mining on the benthic

community structure of the Atlantic 1 Mining Licence Area. Annual Monitoring Report –

1997. Prepared for De Beers Marine (Pty) Ltd by Marine Biology Research Institute, Zoology

Department, University of Cape Town. pp. 44.



PARRY, D.M., KENDALL, M.A., PILGRIM, D.A. & M.B. JONES, 2003. Identification of patch structure

within marine benthic landscapes using a remotely operated vehicle. J. Exp. Mar. Biol.

Ecol., 285– 286: 497–511.

PARRY, G.D. & A. GASSON, 2006. The effect of seismic surveys on catch rates of rock lobsters in

western Victoria, Australia, Fish. Res., 79: 272–284.

PAYNE A.I.L., 1985. The sole fishery off the Orange River, Southern Africa. Int. Symp. Upw. W.

Afr. Inst. Pesq., Barcelona vii: 1063-1079.

PAYNE A.I.L. & A. BADENHORST, 1989. Other Groundfish resources. In: PAYNE A.I.L. & R.J.M.

CRAWFORD (Eds), Oceans of Life off Southern Africa, Vlaeberg, Cape Town, pp. 148-156.

PAYNE, A.I.L. & R.J.M. CRAWFORD, 1989. Oceans of Life off Southern Africa. Vlaeberg, Cape

Town, 380 pp.

PEARSON, W.H., SKALSKI, J.R. & C.I. MALME, 1992. Effects of sounds from a geophysical survey

device on behaviour of captive rockfish (Sebastes spp.). Can J. Fish. Aquat. Sci., 49: 1343-

1356.

PENNEY, A.J., KROHN, R.G. & C.G. WILKE. 1992. A description of the South African tuna fishery in

the southern Atlantic Ocean. ICCAT Col. Vol. Sci. Pap. XXIX(1) : 247-253.

PENNEY, A.J., PULFRICH, A., ROGERS, J., STEFFANI, N. & V. MABILLE, 2007. Project:

BEHP/CEA/03/02: Data Gathering and Gap Analysis for Assessment of Cumulative Effects of

Marine Diamond Mining Activities on the BCLME Region. Final Report to the BCLME mining

and petroleum activities task group. December 2007. 410pp.

PENRY, G.S., 2010. Biology of South African Bryde’s whales. PhD Thesis. University of St Andrews,

Scotland, UK.

PERRY, C., 1998. A review of the impacts of anthropogenic noise on cetaceans. Document SC/50/E9

submitted to the scientific committee of the International Whaling Commission, Muscat,

Oman, 1998. 28 pp + 8 pp appendices.

PETERS, I., BEST, P.B. & M. THORNTON, 2011. Abundance estimates of right whales on a feeding

ground off the west coast of South Africa. Paper SC/S11/RW11 submitted to the IWC

Southern Right Whale Assessment Workshop, Buenos Aires 13-16 Sept. 2011.

PIDCOCK, S., BURTON, C. & M. LUNNEY, 2003. The potential sensitivity of marine mammals to

mining and exploration in the Great Australian Bight Marine Park Marine Mammal

Protection Zone. An independent review and risk assessment report to Environment

Australia. Marine Conservation Branch. Environment Australia, Cranberra, Australia. pp. 85.

PILLAR, S.C., 1986. Temporal and spatial variations in copepod and euphausid biomass off the

southern and and south-western coasts of South Africa in 1977/78. S. Afr. J. mar. Sci., 4:

219-229.

PILLAR, S.C., BARANGE, M. & L. HUTCHINGS, 1991. Influence of the frontal sydtem on the cross-

shelf distribution of Euphausia lucens and Euphausia recurva (Euphausiacea) in the Southern

Benguela System. S. Afr. J. mar. Sci., 11 : 475-481.

PITCHER, G.C., 1998. Harmful algal blooms of the Benguela Current. IOC, World Bank and Sea

Fisheries Research Institute Publication. 20 pp.



PLÖN, S., 2004. The status and natural history of pygmy (Kogia breviceps) and dwarf (K. sima)

sperm whales off Southern Africa. PhD Thesis. Department of Zoology & Entomology

(Rhodes University), p. 551.

POPPER, A.N., 1980. Sound emission and detection by delphinids. Pp 1-52. In: Herman M. (ed.)

Cetacean behaviour; Mechanisms and functions. John Wiley and Sons, New York. 463 pp.

POPPER, A.N., 2003. Effects of anthropogenic sounds on fishes. Fisheries, 28: 24-31.

POPPER, A.N., 2008. Effects of Mid- and High-Frequency Sonars on Fish. Environmental

BioAcoustics, LLC Rockville, Maryland 20853. Contract N66604-07M-6056 Naval Undersea

Warfare Center Division Newport, Rhode Island. 52pp.

POPPER, A.N. & R.R. FAY, 1973. Sound detection and processing by fish: critical review and major

research questions. Brain Behav. Evol., 41: 14-38.

POPPER, A.N. & R.R. FAY, 1999. The auditory periphery in fishes. In: FAY, R.R. & A.N. POPPER

(Eds.) Comparative hearing: Fish and amphibians. Springer, Sydney, pp.43-100

POPPER, A.N., FAY, R.R., PLATT, C. & O. SAND, 2003. Sound detection mechanisms and capabilities

of teleost fishes. In: COLLIN, S.P. & N.J. MARSHALL, (Eds.) Sensory processing in aquatic

environments. Springer-Verlag, New York. Pp. 3-38.

POPPER, A.N., SALMON, M. & K.W. HORCH, 2001. Acoustic detection and communication by

decapod crustaceans. J. Comp. Physiol. A, 187: 83-89.

POPPER, A.N., FEWTRELL, J., SMITH, M.E. & R.D. McCAULEY, 2004. Anthropogenic sound: Effects

on the behavior and physiology of fishes. J. Mar. Technol. Soc., 37: 35-40.

POPPER, A.N., SMITH, M.E., COTT, P.A., HANNA, B.W, MACGILLIVRAY, A.O., AUSTIN, M.E and MANN,

D.A. 2005. Effects of exposure to airgun use on three fish species. J. Acoust. Soc. Am.,

117: 3958 – 3971.

POST, A.L., WASSENBERG, T.J. & V. PASSLOW. 2006. Physical surrogates for macrofaunal

distributions and abundance in a tropical gulf. Marine and Freshwater Research 57:469-483.

POTTS, W.M., SAUER, W.H.H., HENRIQUES, R., SEQUESSEQUE, S., SANTOS, C.V. & P.W. SHAW. 2010.

The biology, life history and management needs of a large sciaenid fish, Argyrosomus

coronus in Angola. African Journal of Marine Science 32 (2): 247 — 258.

PRDW, 2008. Nampower Walvis Bay ESEIA Specialist Study: Hydrodynamic modelling of heated

effluent in marine environment, PRDW Report No. 1024/001, Prestedge Retief Dresner

Wijnberg (Pty) Ltd Consulting Port and Coastal Engineers, 23 pp + 63 pp Figs.

PULFRICH, A. & A.J. PENNEY, 1999. The effects of deep-sea diamond mining on the benthic

community structure of the Atlantic 1 Mining Licence Area. Annual Monitoring Report –

1998. Prepared for De Beers Marine (Pty) Ltd by Marine Biology Research Institute, Zoology

Department, University of Cape Town and Pisces Research and Management Consultants CC.

pp 49.

PULFRICH A. & A.J. PENNEY, 2001. Assessment of the impact of diver-operated nearshore diamond

mining on marine benthic communities near Lüderitz, Namibia. Phase III Report to NAMDEB

Diamond Corporation (Pty) Ltd., Oranjemund, Namibia, 50 pp.



PULFRICH, A., PENNEY, A.J., BRANDÃO, A., BUTTERWORTH, D.S. & M. NOFFKE, 2006. Marine

Dredging Project: FIMS Final Report. Monitoring of Rock Lobster Abundance, Recruitment

and Migration on the Southern Namibian Coast. Prepared for De Beers Marine Namibia, July

2006. 149pp.

RANKIN, S. & W.E. EVANS, 1998. Effect of low frequency seismic exploration signals on the

cetaceans of the Gulf of Mexico. In: The World Marine Mammal Science Conference,

Monaco, 20-24 January 1998, Society for Marine Mammalogy and the European Cetacean

Society, Centre de Recherche sur les Mammifères Marins, La Rochelle, France, p. 110.

RANKIN, S., BAUMANN-PICKERING, S., YACK, T. & J. BARLOW, 2011. Description of sounds recorded

from Longman’s beaked whale, Indopacetus pacificus, Journal of the Acoustical Society of

America: express letters, 130.

RICHARDSON, W.J., WURSIG, B. & C.R. GREENE, 1986. Reactions of bowhead whales, Balaena

mysticetus, to seismic explorations in the Canadian Beaufort sea. J Acoust. Soc. Am., 79(4):

1117-1128.

RICHARDSON, W.J., FRAKER, M.A., WURSIG, B. & R.S. WELLS, 1985. Behaviour of bowhead whales

Balaena mysticetus summering in the Beaufort Sea : Reactions to industrial activities. Biol.

Conserv., 32(3): 195 - 230.

RICHARDSON, W.J., WELLS, R.S. & B. WURSIG, 1985b. Disturbance responses of bowheads, 1980-84.

In: Richardson, W.J. (ed.) Behaviour, disturbance responses and distribution of bowhead

whales Balaena mysticetus in the eastern Beaufort Sea, 1980-84. OCS Study

RICHARDSON, W.J., GREENE, C.R., MALME, C.I. and THOMSON, D.H. 1995. Marine Mammals and

Noise. Academic Press, San Diego, CA.

RIDGWAY, S.H., 1983. Dolphin hearing and sound production in health and illness. pp.247-296. In:

Far, R.R and Gourevitch, G. (Eds.). Hearing and other senses. Amphora press, Groton, CT.

405 pp.

RIDGWAY, S.H., E.G. WEVER, J.G. MCCORMICK, J. PALIN & J.H. ANDERSON, 1969. Hearing in the

giant sea turtle, Chelonia mydas. Proceedings of the National Academy of Sciences USA, 64:

884-890.

ROEL, B.A., 1987. Demersal communities off the west coast of South Africa. South African Journal

of Marine Science 5: 575-584.

ROGERS, A.D., 1994. The biology of seamounts. Advances in Marine Biology, 30: 305–350.

ROGERS, A.D., 2004. The biology, ecology and vulnerability of seamount communities. IUCN, Gland,

Switzerland. Available at: www.iucn.org/themes/ marine/pubs/pubs.htm 12 pp.

ROGERS, A.D., CLARK, M.R., HALL-SPENCER, J.M. & K.M. GJERDE, 2008. The Science behind the

Guidelines: A Scientific Guide to the FAO Draft International Guidelines (December 2007)

For the Management of Deep-Sea Fisheries in the High Seas and Examples of How the

Guidelines May Be Practically Implemented. IUCN, Switzerland, 2008.

ROGERS, J., 1977. Sedimentation on the continental margin off the Orange River and the Namib

Desert. Unpubl. Ph.D. Thesis, Geol. Dept., Univ. Cape Town. 212 pp.



ROGERS, J. & J.M. BREMNER, 1991. The Benguela Ecosystem. Part VII. Marine-geological aspects.

Oceanogr. Mar. Biol. Ann. Rev., 29: 1-85.

ROLLAND, R.M., PARKS, S.E., et al. 2012. Evidence that ship noise increases stress in right whales.

Proceedings of the Royal Society B Available online: 1-7. doi:10.1098/rspb.2011.2429

ROMANO, T.A., KEOGH, M.J., KELLY, C., FENG, P., BERK, L., SCHLUNDT, C.E., CARDER, D.A. & J.J.

FINNERAN, 2004. Anthropogenic sound and marine mammal health: measures of the

nervous and immune systems before and after intense sound exposure., Canadian Journal of

Fisheries and Aquatic Sciences, 61: 1124–1134.

ROSE, B. & A. PAYNE, (1991). Occurrence and behavior of the Southern right whale dolphin

Lissodelphis peronii off Namibia. Marine Mammal Science 7: 25-34.

ROSENBAUM, H.C., POMILLA, C., MENDEZ, M., LESLIE, M.S., BEST, P.B., FINDLAY, K.P., MINTON, G.,

ERSTS, P.J., COLLINS, T., ENGEL, M.H., BONATTO, S., KOTZE, P.G.H., MEŸER, M.,

BARENDSE, J., THORNTON, M., RAZAFINDRAKOTO, Y., NGOUESSONO, S., VELY, M. & J.

KISZKA, 2009. Population structure of humpback whales from their breeding grounds in the

South Atlantic and Indian Oceans. PLoS One, 4 (10): 1-11.

ROSENBAUM, H.C., MAXWELL, S., KERSHAW, F. & B.R. MATE, 2014. Quantifying long-range

movements and potential overlap with anthropogenic activities of humpback whales in the

South Atlantic Ocean. In press. Conservation Biology.

ROSS, G.J.B., 1979. Records of pygmy and dwarf sperm whales, genus Kogia, from southern Africa,

with biological notes and some comparisons. Annals of the Cape Province Museum (Natural

History) 11: 259-327.

ROUX, J-P., BEST, P.B. & P.E. STANDER. 2001. Sightings of southern right whales (Eubalaena

australis) in Namibian waters, 1971-1999. J. Cetacean Res. Manage. (Special Issue). 2: 181–

185.

ROUX, J-P., BRADY, R. & P.B. BEST, 2011. Southern right whales off Namibian and their relationship

with those off South Africa. Paper SC/S11/RW16 submitted to IWC Southern Right Whale

Assessment Workshop, Buenos Aires 13-16 Sept. 2011.

SÆTRE, R. & E. ONA, 1996. Seismiske undersøkelser og skader på fiskeegg og -larver; en vurdering

av mulige effekter på bestandsnivå. Havforskningsinstituttet, Fisken og Havet, 8 - 1996.

25pp.

SALAS, F., MARCOS, C., NETO, J.M., PATRICIO, J., PÉREZ-RUZAFA, A. & J.C. MARQUES. 2006. User-

friendly guide for using benthic ecological indicators in coastal and marine quality

assessment. Ocean and Coastal management 49: 308-331.

SALTER, E. & J. FORD, 2001. Holistic Environmental Assessment and Offshore Oil Field Exploration

and Production. Mar Poll. Bull., 42(1): 45-58.

SAMARRA, F.I.P., DEECKE, V.B., VINDING, K., RASMUSSEN, M.H., SWIFT, R.J. & P.J.O. MILLER, 2010.

Killer whales (Orcinus orca) produce ultrasonic whistles, Journal of the Acoustical Society of

America, 128.

SANTULLI, A., MODICA, A., MESSINA, C., CEFFA, L., CURATOLO, A., RIVAS, G., FABI, G. & V.

D’AMELIO, 1999. Biochemical Responses of European Sea Bass (Dicentrarchus labrax L.) to



the Stress Induced by Off Shore Experimental Seismic Prospecting. Mar. Poll. Bull., 38(12):

1105-1114.

SAVAGE, C., FIELD, J.G. & R.M. WARWICK, 2001. Comparative meta-analysis of the impact of

offshore marine mining on macrobenthic communities versus organic pollution studies. Mar

Ecol Prog Ser., 221: 265-275.

SCHLUNDT, C.E., FINNERAN, J.J., CARDER, D., & S.H. RIDGWAY, 2000. Temporary shifts in masked

hearing thresholds (MTTS) of bottlenose dolphins, Tursiops truncatus, and white whales,

Delphinapterus leucas, after exposure to intense tones. J. Acoust. Soc. Am., 107: 3496–

3508.

SCHNEIDER, G. & MUYONGO, A., 2013. Hydrocarbon exploration and Albacore Tuna fisheries – A

classical example for the role of BCC in joint and transboundary management of the BCLME.

Presented at the Benguela Current Commission Science Forum, 24 September 2013.

SCHOLIK, A.R. & H.Y. YAN, 2001. Effects of underwater noise on auditory sensitivity of a cyprinid

fish. Hearing Res., 152: 17-24.

SCHOLIK, A.R. & H.Y. YAN, 2002. The effects of noise on the auditory sensitivity of the bluegill

sunfish, Lepomis macrochirus. Comp. Biochem. Physiol., 133A: 43-52.

SCHUSTERMAN, R.J., 1981. Behavioral capabilities of seals and sea lions: A review of their hearing,

visual, learning and diving skills. Psychol. Rec., 31(2): 125-143.

SHANNON, L.J., C.L. MOLONEY, A. JARRE & J.G. FIELD, 2003. Trophic flows in the southern

Benguela during the 1980s and 1990s. Journal of Marine Systems, 39: 83 - 116.

SHANNON, L.V., 1985. The Benguela Ecosystem. Part 1. Evolution of the Benguela, physical

features and processes. Oceanogr. Mar. Biol. Ann. Rev., 23: 105-182.

SHANNON, L.V. & F.P. ANDERSON, 1982. Application of satellite ocean colour imagery in the study

of the Benguela Current system. S. Afr. J. Photogrammetry, Remote Sensing and

Cartography, 13(3): 153-169.

SHANNON, L.V. & J.G. FIELD, 1985. Are fish stocks food-limited in the southern Benguela pelagic

ecosystem ? Mar. Ecol. Prog. Ser., 22(1) : 7-19.

SHANNON, L.V. & G. NELSON, 1996. The Benguela: Large scale features and processes and system

variability. In: The South Atlantic: Present and Past Circulation. WEFER, G., BERGER, W.

H., SIEDLER, G. & D. J. WELLS (eds.). Berlin; Springer: 163-210.

SHANNON L.V. & S. PILLAR, 1985. The Benguela Ecosystem III. Plankton. Oceanography & Marine

Biology: An Annual Review, 24: 65-170.

SHANNON, L.V. & M.J. O’TOOLE, 1998. BCLME Thematic Report 2: Integrated overview of the

oceanography and environmental variability of the Benguela Current region. Unpublished

BCLME Report, 58ppSIMMONDS, M.P., and LOPEZ – JURADO, L.F. 1991. Nature. 337: 448.

SHAUGHNESSY P.D., 1979. Cape (South African) fur seal. In: Mammals in the Seas. F.A.O. Fish. Ser.,

5, 2: 37-40.

SHILLINGTON, F. A., PETERSON, W. T., HUTCHINGS, L., PROBYN, T. A., WALDRON, H. N. & J. J.

AGENBAG, 1990. A cool upwelling filament off Namibia, South West Africa: Preliminary

measurements of physical and biological properties. Deep-Sea Res., 37 (11A): 1753-1772.



SHINE, K., 2006. Biogeographic patterns and diversity in demersal fish off the south and west coasts

of south Africa: Implications for conservation. MSc thesis, Universty of Cape Town.

SIMRAD, P., LACE, N., GOWANS, S., QUINTANA-RIZZO, E., KUCZAJ II, S.A., WELLS, R.S. & D.A. MANN,

2012. Low frequency narrow-band calls in bottlenose dolphins (Tursiops truncatus): Signal

properties, function, and conservation implications, Journal of the Acoustical Society of

America 130: 3068-3076.

SINK, K. & T. SAMAAI, 2009. Identifying Offshore Vulnerable Marine Ecosystems in South Africa.

Unpublished Report for South African National Biodiversity Institute, 29 pp.

SIMMONDS, M.P. & L.F. LOPEZ – JURADO, 1991. Nature. 337: 448.

SKALSKI, J.R., PEARSON, W.H. & C.I. MALME, 1992. Effects of sounds from a geophysical survey

device on catch-per-unit-effort in a hook-and -line fishery for Rockfish (Sebastes spp.) Can

J. Fish. Aquat. Sci., 49: 1357-1365.

SLOTTE, A., HANSEN, K., DALEN, J. & E. ONA, 2004. Acoustic mapping of pelagic fish distribution

and abundance in relation to a seismic shooting area off the Norwegian west coast.

Fisheries Research, 67: 143–150.

SMALE, M.J., ROEL, B.A., BADENHORST, A. & J.G. FIELD, 1993. Analysis of demersal community of

fish and cephalopods on the Agulhas Bank, South Africa. Journal of Fisheries Biology 43:169-

191.

SMITH, G.G & G.P. MOCKE, 2002. Interaction between breaking/broken waves and infragravity-

scale phenomena to control sediment sediment suspension and transport in the surf zone.

Marine Geology, 187: 320-345.

SMITH, M.E., KANE, A.S. & A.N. POPPER, 2004. Noise-induced stress response and hearing loss in

goldfish (Carassius auratus). J. Exp. Biol., 207: 427-435.

SMITH, M.E., A.B. COFFIN, D.L. MILLER, & A.N. POPPER, 2006. Anatomical and functional recovery

of the goldfish (Carassius auratus) ear following noise exposure. Journal of Experimental

Biology, 209: 4193-4202.

SOUTHALL, B.L., A.E. BOWLES, W.T. ELLISON, J.J. FINNERAN, R.L. GENTRY, C.R. GREENE, JR., D.

KASTAK, D.R. KETTEN, J.H., MILLER, P.E. NACHTIGALL, W.J. RICHARDSON, J.A. THOMAS &

P.L. TYACK, 2007. Marine mammal noise exposure criteria: initial scientific

recommendations. Aquatic Mammals, 33(4): 411-522.

SPRFMA, 2007: Information describing seamount habitat relevant to the South Pacific Regional

Fisheries Management Organisation.

STEFFANI, N., 2007a. Biological Baseline Survey of the Benthic Macrofaunal Communities in the

Atlantic 1 Mining Licence Area and the Inshore Area off Pomona for the Marine Dredging

Project. Prepared for De Beers Marine Namibia (Pty) Ltd. pp. 42 + Appendices.

STEFFANI, N., 2007b. Biological Monitoring Survey of the Macrofaunal Communities in the Atlantic 1

Mining Licence Area and the Inshore Area between Kerbehuk and Bogenfels. 2005 Survey.

Prepared for De Beers Marine Namibia (Pty) Ltd. pp. 51 + Appendices.



STEFFANI, N., 2009a. Biological Monitoring Surveys of the Benthic Macrofaunal Communities in the

Atlantic 1 Mining Licence Area and the Inshore Area – 2006/2007. Prepared for De Beers

Marine Namibia (Pty) Ltd. (Confidential Report) pp. 81 + Appendices.

STEFFANI, N., 2009b. Assessment of Mining Impacts on Macrofaunal Benthic Communities in the

Northern Inshore Area of the De Beers ML3 Mining Licence Area - 18 Months Post-mining.

Prepared for De Beers Marine. pp. 47 + Appendices.

STEFFANI, N., 2009c. Baseline Study on Benthic Macrofaunal Communities in the Inner Shelf Region

and Assessment of Mining Impacts off Chameis. November 2009. Prepared for Namdeb. pp.

45 + Appendices.

STEFFANI, C.N., 2010. Assessment of mining impacts on macrofaunal benthic communities in the

northern inshore area of the De Beers Mining Licence Area 3 – 2010 . Prepared for De Beers

Marine (South Africa). pp 30 + Appendices.

STEFFANI, N., 2011. Environmental Impact Assessment for the dredging of Marine Phosphate

Enriched Sediments from Mining Licence Area No. 170. Specialist Study No. 1c: Marine

Benthic Specialist Study for a Proposed Development of Phosphate Deposits in the Sandpiper

Phosphate Licence Area off the Coast of Central Namibia. Prepared for Namibian Marine

Phosphate (Pty) Ltd. November 2011. 72 pp.

STEFFANI, C.N., 2012. Assessment of Mining Impacts on Macrofaunal Benthic Communities in the

Northern Inshore Area of the ML3 Mining Licence Area - 2011. Prepared for De Beers Marine

(South Africa), July 2012, 54pp.

STEFFANI, C.N. & A. PULFRICH, 2004a. Environmental Baseline Survey of the Macrofaunal Benthic

Communities in the De Beers ML3/2003 Mining Licence Area. Prepared for De Beers Marine

South Africa, April 2004., 34pp.

STEFFANI, N. & A. PULFRICH, 2004b. The potential impacts of marine dredging operations on

benthic communities in unconsolidated sediments. Specialist Study 2. Specialist Study for

the Environmental Impact Report for the Pre-feasibility Phase of the Marine Dredging

Project in Namdeb’s Atlantic 1 Mining Licence Area and in the nearshore areas off Chameis.

Prepared for PISCES Environmental Services (Pty) Ltd, September 2004.

STEFFANI, C.N. & A. PULFRICH, 2007. Biological Survey of the Macrofaunal Communities in the

Atlantic 1 Mining Licence Area and the Inshore Area between Kerbehuk and Lüderitz 2001 –

2004 Surveys. Prepared for De Beers Marine Namibia, March 2007, 288pp.

STONE, C.J., 2003. The effects of seismic activity on marine mammals in UK waters, 1998-2000.

JNCC Report No 323. Joint Nature Conservation Committee, Aberdeen. ISSN 0963-8091.

STUART, V. 1982. Absorbed ration, respiratory costs and resultant scope for growth in the mussel

Aulacomya ater (Molina) fed on a diet of kelp detritus of different ages. Mar. Biol. Letters.

3: 289–306.

STUART, V., FIELD, J.G., & R.C. NEWELL, 1982. Evidence for the absorption of kelp detritus by the

ribbed mussel Aulacomya ater using a new 51Cr-labelled microsphere technique. Mar. Ecol.

Prog. Ser. 9: 263–271.

SUZUKI, H., HAMADA, E., SAITO, K., MANIWA, Y. & Y. SHIRAI, 1980. The influence of underwater

sound on marine organisms. J. Navig., 33: 291-295.



TAUNTON-CLARK J. 1985. The formation, growth and decay of upwelling tongues in response to the

mesoscale windfield during summer. In: South African Ocean Colour and Upwelling

Experiment. Shannon L.V. (ed.). Sea Fisheries Research Institute, Cape Town. pp 47-62.

TAVOLGA, W.N. & J. WOODINSKY, 1963. Auditory capacities in fish. Pure tone thresholds in nine

species of marine teleosts. Bull. Am. Mus. Nat. Hist., 126: 177-239.

TAVOLGA, W.N., POPPER, A.N. & R.R. FAY, 1981. Hearing and sound communication in fishes.

Springer-Verlag, New York. 608 pp.

THOMAS, J., CHUN, N., AU, W.W.L. & K. PUGH, 1988. Underwater audiogram of a false killer whale

(Pseudorca crassidens). J. Acoust. Soc. Am., 84(3): 936-940.

THOMISCH, K., BOEBEL, O., CLARK, C.W., HAGEN, W., SPIESECKE, S., ZITTERBART, D.P. & I. VAN

OPZEELAND, 2016. Spatio-temporal patterns in acoustic presence and distribution of

Antarctic blue whales Balaenoptera musculus intermedia in the Weddell Sea. Endangered

Species Research, 30: 239-253.

TIMONIN, A.G., ARASHKEVICH, E.G., DRITS, A.V. & T.N. SEMENOVA, 1992. Zooplankton dynamics in

the northern Benguela ecosystem, with special reference to the copepod Calanoides

carinatus. In: PAYNE, A.I.L., BRINK, K.H., MANN, K.H. & R. HILBORN (Eds). Benguela Trophic

Functioning. S. Afr. J. mar. Sci. 12: 545–560.

TOMALIN, B.J., 1993. Migrations of spiny rock lobsters, Jasus lalandii, at Lüderitz : Environmental

causes, and effects on the fishery and benthic ecology. M.Sc thesis, University of Cape

Town, pp 1-99.

TURL, C.W., 1993. Low-frequency sound detection by a bottlenose dolphin. J. Acoust. Soc. Am.,

94(5): 3006-3008.

TURNPENNY, A.W.H. & J.R. NEDWELL, 1994. The effects on marine fish, diving mammals and birds

of underwater sound generated by seismic surveys. Rep. from Fawley Aquatic Research

Laboratories Ltd. 40 pp + 9 pp appendices.

TYACK, P.L., 2008. Implications from marine mammals of large-scale changes in the marine

acoustic environment, Journal of Mammalogy, 89: 549-558.

TYACK, P.L. & C.W. CLARK, 2000. Communication and acoustic behavior of dolphins and whales.

In: Au, W.W.L. & R.R. Fay (Eds) Hearing by Whales and Dolphins, Springer, New York, pp.

156-224.

TYACK, P.L., ZIMMER, W.M.X., MORETTI, D., SOUTHALL, B.L., CLARIDGE, D.E., DURBAN, J.W.,

CLARK, C.W., et al., 2011. Beaked Whales Respond to Simulated and Actual Navy Sonar,

6(3). doi:10.1371/journal.pone.0017009

UNITED STATES DEPARTMENT OF THE INTERIOR, 2007. Notice to Lessees and Operators (NTL) of

federal oil, gas, and sulphur leases in the outer continental shelf, Gulf of Mexico OCS

Region: Implementation of Seismic Survey Mitigation Measures and Protected Species

Observer Program. NTL No. 2007-G02.

VAN DALFSEN, J.A., ESSINK, K., TOXVIG MADSEN, H., BIRKLUND, J., ROMERO, J. & M. MANZANERA,

2000. Differential response of macrozoobenthos to marine sand extraction in the North Sea

and the Western Mediterranean. ICES J. Mar. Sci., 57: 1439–1445.



VAN DER WOUDE, S.E., 2009. Bottlenose dolphins (Tursiops truncatus) moan as low in frequency as

baleen whales, Journal of the Acoustical Society of America, 126: 1552-1562.

VASCONCELOS, R.O., AMORIM, M.C.P. & F. LADICH, 2007. Effects of ship noise on the detectability

of communication signals in the Lusitanian toadfish. J. Exp. Biol. 210: 2104–2112.

VISSER, G.A., 1969. Analysis of Atlantic waters off the coast of southern Africa. Investigational

Report Division of Sea Fisheries, South Africa, 75: 26 pp.

VU, E. T., RISCH, D., CLARK, C.W., GAYLORD, S., HATCH, L.T., THOMPSON, M.A., WILEY, D.N. &

S.M. VAN PARIJS, 2012. Humpback whale song occurs extensively on feeding grounds in the

western North Atlantic Ocean, Aquatic Biology, 14: 175-183.

WARD, L.G., 1985. The influence of wind waves and tidal currents on sediment resuspension in

Middle Chesapeake Bay. Geo-Mar. Letters, 5: 1-75.

WALKER, D.R & W.T. PETERSON, 1991. Relationships between hydrography, phytoplankton

production, biomass, cell size and species composition, and copepod production in the

southern Benguela upwelling system in April 1988. S. Afr. J. mar. Sci., 11: 289-306

WARDLE, C.S., CARTER, T.J., URQUHART, G.G., JOHNSTONE, A.D.F., ZIOLKOWSKI, A.M., HAMPSON,

G. & D. MACKIE, 2001. Effects of seismic air guns on marine fish. Cont. Shelf Res., 21:

1005-1027.

WARWICK, R.M., 1993. Environmental impact studies on marine communities: Pragmatical

considerations. Australian Journal of Ecology. 18: 63-80.

WARWICK, R.M., GOSS-CUSTARD, J.D., KIRBY, R., GEORGE, C.L., POPE, N.D. & A.A. ROWDEN, 1991.

Static and dynamic environmental factors determining the community structure of estuarine

macrobenthos in SW Britain: why is the Severn estuary different? J. Appl. Ecol., 28: 329–

345.

WARTZOK, D., A.N. POPPER, J. GORDON, & J. MERRILL, 2004. Factors affecting the responses of

marine mammals to acoustic disturbance. Mar. Technology Soc. J., 37(4): 6-15.

WATKINS, W.A. 1986. Whale reactions to human activities in Cape Cod waters. Mar. Mamm. Sci.,

2(4): 251-262.

WATKINS, W.A. & D. WARTZOK, 1985. Sensory biophysics of marine mammals. Mar. Mamm. Sci.,

1(3): 219-260.

WEBB, C.L.F. & N.J. KEMPF, 1998. The impact of shallow water seismic surveys in sensitive areas.

Society for Petroleum Engineers Technical Paper SPE46722.

WEILGART, L.S., 2007. A brief review of known effects of noise on marine mammals, International

Journal of Comparative Psychology, 20: 159-168.

WEIR, C.R., 2007. Observations of Marine Turtles in Relation to Seismic Airgun Sound off Angola.

Marine Turtle Newsletter, 116: 17-20.

WEIR C.R., 2008. Bottlenose dolphins (Tursiops truncatus) off flamingos, Angola. Photo-

identification catalogue. Ketos Ecology Version 1, August 2008. www.ketosecology.co.uk.

WEIR, C.R. 2008. Short-Finned Pilot Whales (Globicephala macrorhynchus) Respond to an Airgun

Ramp-up Procedure off Gabon. Aquatic Mammals, 34(3): 349-354,



WEIR, C.R., 2011. Distribution and seasonality of cetaceans in tropical waters between Angola and

the Gulf of Guinea. African Journal of Marine Science 33(1): 1-15.

WEIR, C.R., COLLINS, T., CARVALHO, I. & H.C. ROSENBAUM, 2010. Killer whales (Orcinus orca) in

Angolan and Gulf of Guinea waters, tropical West Africa. Journal of the Marine Biological

Association of the U.K. 90: 1601– 1611.

WEIR, C.R, DOLMAN, S.J. & M.P. SIMMONDS, 2006. Marine mammal mitigation during seismic

surveys and recommendations for worldwide standard mitigation guidance. Paper presented

to IWC SC, SC/58/E12.

WEISSENBERGER, J. & D.P. ZITTERBARD, 2012. Surveillance of Marine Mammals in the Safety Zone

Around an Air Gun Array With the Help ofa 360° Infrared Camera System. SPE/APPEA

International Conference on Health, Safety, and Environment in Oil and Gas Exploration and

Production, Perth, Australia, 11–13 September 2012

WELLER, D.W., IVASHCHENKO, Y.V., TSIDULKO, G.A., BURDIN, A.M., & R.L. BROWNELL, 2002.

Influence of seismic surveys on western gray whales off Sakhalin Island, Russia in 2001.

Document SC/54/BRG14 submitted to the Scientific Committee of the International Whaling

Commission, 2002.

WEVER, E., HERMAN, P., SIMMONS, J. & D. HERTZLER, 1969. Hearing in the Blackfooted Penguin,

Spheniscus demersus, as Represented by the Cochlear Potentials. PNAS 63(3): 676-680.

WHITE, M.J., NORRIS, J., LJUNGBLAD, D., BARON, K. & G. DI SCIARRA, 1978. Auditory thresholds of

two beluga whales (Delphinapterus leucas). HSWRI Tech Rep. 78-109. Report from Hubbs/

Sea World Res. Inst., San Diego, Ca. 35pp.

WHITEHEAD, H., 2002. Estimates of the current global population size and historical trajectory for

sperm whales. Marine Ecology Progress Series, 242: 295-304.

WICKENS, P., 1994. Interactions between South African Fur Seals and the Purse-Seine Fishery.

Marine Mammal Science, 10: 442–457.

WILKINSON, S. & D.W. JAPP, 2009. Specialist Study on the Impact on the Fishing Industry. In: CCA

Environmental (Pty) Ltd. 2009. Environmental Impact Report for Proposed Exploration Well

Drilling Programme Block 1 (West Coast, South Africa) by PetroSA (Pty) Ltd.

WINN, H.E. & L.K. WINN, 1978. The song of the humpback whale Megaptera novaeangliae in West-

Indies, Marine Biology, 47: 97-114.

WRIGHT, A.J. et al. 2007. Anthropogenic Noise as a Stressor in Animals: A Multidisciplinary

Perspective, International Journal of Comparative Psychology, 20: 250-273.

YATES, M.G., GOSS-CUSTARD, J.D., MCGRORTY, S.M., LAKHANI, DIT DURRELL, S.E.A., LEVIT,

CLARKE, R.T., RISPIN, W.E., MOY, I., YATES, T., PLANT, R.A. & A.J. FROST, 1993. Sediment

characteristics, invertebrate densities and shorebird densities on the inner banks of the

Wash. J. Appl. Ecol., 30: 599– 614.

ZAJAC, R.N., LEWIS, R.S., POPPE, L.J., TWICHELL, D.C., VOZARIK, J., & M.L. DIGIACOMO-COHEN,

2000. Relationships among sea-floor structure and benthic communities in Long Island

Sound at regional and benthoscape scales. J. Coast. Res., 16: 627– 640.



ZETTLER, M.L., BOCHERT, R. & F. POLLEHNE. 2009. Macrozoobenthos diversity in an oxygen

minimum zone off northern Namibia. Marine Biology 156:1949-1961.

ZEYBRANDT, F. & J.I. BARNES, 2001. Economic characteristics of demand in Namibia's marine

recreational shore fishery. South African Journal of Marine Science, 23: 145-156.

ZITTERBART, D.P., KINDERMANN, L., BURKHARDT, E. & O. BOEBEL, 2013. Automatic Round-the-

Clock Detection of Whales for Mitigation from Underwater Noise Impacts. PLoS ONE 8(8):

e71217. doi:10.1371/journal.pone.0071217

ZOUTENDYK, P., 1992. Turbid water in the Elizabeth Bay region: A review of the relevant

literature. CSIR Report EMAS-I 92004.

ZOUTENDYK, P., 1995. Turbid water literature review: a supplement to the 1992 Elizabeth Bay

Study. CSIR Report EMAS-I 95008.

Other sources consulted during this study include:

ANON (date Unknown). Western Australian Department of Mineral and Petroleum Resources

Petroleum Information Series – Guidelines Sheet 1. www.anp.gov.br/brnd/round5

/round5/guias/sismica/biblio/Guidelines.pdf

ANON, 2009. CGGVeritas 2D Marine Seismic Survey Exploration Permit Area W09-1, Browse Basin,

Western Australia. Environmental Plan: Public Summary. www.ret.gov.au/.../

24335_CGGVeritas_2DMSS_PublicSummary.pdf.

FUGRO (date Unknown). Zeemeermin MC3D Marine Seismic Survey. Environment Plan: Public

Summary. www.docstoc.com/.../ZEEMEERMIN-MC3D-MARINE-SEISMIC-SURVEY-ENVIRONMENT

-PLAN-PUBLIC-SUMMARY

HEYNEN, T., 2008. Bicuda 2D Seismic Survey [Draft] Environmental Management Plan. Compiled

for Eni Timor Leste S.p.A. TL-HSE-PL-001 (Rev 0). www.laohamutuk.org.

UNITED STATES DEPARTMENT OF THE INTERIOR - MINERALS MANAGEMENT SERVICE, 2008. Site-

specific Environmental Assessment of Geological & Geophysical Prospecting for mineral

resources Application No. E-8-01 for Post, Buckley, Schuh, and Jernigan’s (PBS&J).

www.cspinet.org/new/pdf/e-8-01_sea.pdf

WOODSIDE, 2005. Trim 3D Marine Seismic Survey Environment Plan. www.pir.sa.gov.au

/__.../epp29_woodside_trim3d_envplan_www.pdf.

WOODSIDE, 2007. Environment Plan Summary: Maxima 3D Marine Seismic Survey, Scott Reef.

APPENDIX 4

PUBLIC PARTICIPATION PROCESS

Appendix 4.1: I&AP database

Appendix 4.2: I&AP notification letter

Appendix 4.3: Advertisements

Appendix 4.4: I&AP correspondence on the EIA Report

Appendix 4.5: Comments and Responses Report

APPENDIX 4.1

I&AP DATABASE

CCA Environmental (Pty) Ltd

Page 1 of 2

SPEC13N3D - DATABASE

2017/10/16

Selected Clients Organisation and Name List (2 column)

- - - - - - - - - -

Mr J Burgess- - - - - - - - - -

Mr S Kadhila- - - - - - - - - -

Dr J Kemper- - - - - - - - - -

Mr A Lebis- - - - - - - - - -

Ms C Mannheimer- - - - - - - - - -

Ms S Master- - - - - - - - - -

Ms S Neumbo- - - - - - - - - -

Dr B Oelofsen- - - - - - - - - -

Mr P Pahl- - - - - - - - - -

Mr J Pretorius- - - - - - - - - -

Mr R Shimooshili- - - - - - - - - -

Mr P LeveilleAfri-Can Marine Minerals Corp.

Mr D DiamantinoAgatha Bay

Mr B VuAlberta Oilsands Inc

DR J-P RouxAnimal Demography Unit

Mr A SalmanArcadia

Mr I MbiliAtab Fishing

Mr H HamukuayaBenguela Current Commission

Ms A OlivierBenguella Sea Products

Mr R EyeroCadilu Fishing

Mr A MillhollandCanadian Overseas Petroleum Ltd

Mr D JappCapricon Marine Environment (CapMarine)

Ms S WilkinsonCapricon Marine Environment (CapMarine)

Mr BaumgartnerChariot Oil & Gas

Mr R MwanachilengaChariot Oil & Gas

Mr I ThomasChariot Oil & Gas

Ms S RouxCoastal Environmental Trust of Namibia

Ms N GreenConfederation of Namibian Fishing Association

Mr H TheronConsortium Fishing

Mr G SantanaCowan Petroleo e Gas

CPT NiftyCrab Association

Mr Y NishikawaCrab Association

TAFCO OverseasCrab Association

Mr S TikawaCrab Association

Mr D RusselDavid Russel Fisheries Consultancy

Mr R GrayDe Beers Consolidated Diamond Mines

Mrs R Van der MerweDe Beers Marine Namibia/Namdeb

Mr N HaganDebmarine Namibia

Mr E PataDemersal Fishing

Mr D DiazDiaz Fishing

Mr B KohrsEarthlife Namibia

Mr C KinleyECO Oil & Gas

Mr E EhangaEhanga Fishing

The ManagerEnergulf Resource Inc

Mr P ConradieEtosha Fishing Corp (Pty) Ltd

Mr P GreeffEtosha Fishing Corp (Pty) Ltd

Ms Y GreeffFreddie Fish Processors

Mr K HatutungaHatutunga Fishing

Mr D DiamantinoHelgoland Fishing

Mr T AitkenHRT America Inc

Mr F de Oliveira FilhoHRT Oil & Gas

The ManagerHuab Fishing

Mr H KauneKodago Fishing

Mr H TheronKuiseb Fish Products

Mr A WarneKunene

Mr JP MalherbeLalandi (Namfish)

Mr M MatLalandii Holdings

Mr M HambudaLarge Pelagic and Hake Longlining Ass. of Namibia

Mr K LauferLarge Pelagic and Hake Longlining Ass. of Namibia

Mr D RussellLarge Pelagic and Hake Longlining Ass. of Namibia

Mr J van ZylLarge Pelagic and Hake Longlining Ass. of Namibia

Mr H BurgerMarco Fishing (Pty) Ltd

Mr AJ LouwMarco Fishing (Pty) Ltd

Mr D PelerinMaurel Et Prom SA

Mr J MoutonMidwater Trawling Association of Namibia (MTA)

Ms S AngulaMinistry of Environment and Tourism

Mr SN NegumboMinistry of Environment and Tourism

Mr T NghitilaMinistry of Environment and Tourism

Mr P AmutenyaMinistry of Fisheries and Marine Resources (MFMR)

Mr M BlockMinistry of Fisheries and Marine Resources (MFMR)

Mr B CurrieMinistry of Fisheries and Marine Resources (MFMR)

Ms D'almeidaMinistry of Fisheries and Marine Resources (MFMR)

DirectorMinistry of Fisheries and Marine Resources (MFMR)

Ms L DulaMinistry of Fisheries and Marine Resources (MFMR)

Ms A ErastusMinistry of Fisheries and Marine Resources (MFMR)

Ms K GroblerMinistry of Fisheries and Marine Resources (MFMR)

Mrs U HiveluahMinistry of Fisheries and Marine Resources (MFMR)

Dr H HoltzhausenMinistry of Fisheries and Marine Resources (MFMR)

Mr T IlendeMinistry of Fisheries and Marine Resources (MFMR)

Mr P KaingeMinistry of Fisheries and Marine Resources (MFMR)

Mr J KathenaMinistry of Fisheries and Marine Resources (MFMR)

Ms A KreinerMinistry of Fisheries and Marine Resources (MFMR)

Mr M MaurihungirireMinistry of Fisheries and Marine Resources (MFMR)

Mr P SchivuteMinistry of Fisheries and Marine Resources (MFMR)

CCA Environmental (Pty) Ltd

Page 2 of 2

SPEC13N3D - DATABASE

2017/10/16

Selected Clients Organisation and Name List (2 column)

Ms J SheyadivaMinistry of Fisheries and Marine Resources (MFMR)

Mr B TjizooMinistry of Fisheries and Marine Resources (MFMR)

Mr C McleodMinistry of Mines and Energy

Ms G SchneiderMinistry of Mines and Energy

Ms M ShinoMinistry of Mines and Energy

Mr J MuzanimaMinistry of Works and Transport and Communication

Mr P MwatileMinistry of Works, Transport and Communication

Mr MM NangoloMinistry of Works, Transport and Communication

DirectorMorcar Fishing

Namboty Group

Mr I MulungaNamcor

Mr C AugustNamdeb Diamond Corporation

Mr A BaumannNamdeb Diamond Corporation

M A MalherbeNamibia Nature Foundation

Mr A MansinhoNamibian Crab Association

Mr S ElwinNamibian Dolphin Project

Ms H-M BothaNamibian Environment & Wildlife Society

Mr P CunninghamNamibian Environment & Wildlife Society

Namibian Fisherman Association

Mr LouwNamibian Hake & Tuna Longline Assoc

Mr M AmukwaNamibian Hake Association

Mr GoagosebNamibian Hake Association

Mr T KathindiNamibian Hake Association

The SecretaryNamibian Hake Association

Mr M AmbundaNamibian Large Pelagic Association

Mr R CoppinNamibian Large Pelagic Association

Mr du PlessisNamibian Mariculture Association

Mr T NambahuNamibian Marine Resources

Mr C JacobsNamibian Midwater Trawling Association

Mr P HitulaNamibian Monk and Sole Association

Mrs L MareeNamibian Monk and Sole Association

Mr E Van DykNamibian Pelagic Fishing Association

Ms M Van WykNamibian Pelagic Fishing Association

Mr H ViljoenNamibian Pelagic Fishing Association

Mr D SchoombeNamibian Rock Lobster Fishing Association

RD ShanjengangeNamibian Rock Lobster Fishing Association

Mr R WoltersNamibian Rock Lobster Fishing Association

Mr M CooperNAMPORT

Mr W MutwaNAMPORT

Mr B UirabNAMPORT

Mr J ArnoldNamsov Fishing Enterprises(Pty) Ltd

Mr M NghipunyaNational Fishing Corporation

Mr OM KandjozeNational Petroleum Corporation of Namibia

The ManagerNautilus Fishing

Mr E ReedNewsbase Limited

Mr JR CanosaNovanam Namibia

Mr J MagdalenaNovanam Namibia

Mr M TordesillasNovanam Namibia

Mr O ShigwanaOmakete Investments

Mr O SandroOmpangona Fishing

Mr O OmuhukaOmuhuka Holdings

Mr R de CastroOndjaba Fisheries cc

Ms M HlasekOndjaba Fisheries cc

Mr E EnegbulieOranto Petroleum Limited

Mr O DiamantinoOryx Fisheries

Mr G KeggePancontinental Namibia (Pty) Ltd

Mr B RushworthPancontinental Namibia (Pty) Ltd

Mr A TordesillasPescanova Group

Mr G De FrancescoPetro Viking Energy Inc.

Mr L GlimhagenPetro Viking Energy Inc.

Mr J RizzoPetrobras

Dr A PulfrichPisces Environmental Services

Dr S ElwenSea Search Africa

Ms K ChestertonSerica Energy Namibia

Mr M FleggSerica Energy Namibia

Mr K KarimShoreline Energy Internationa

Ms PS KaulingeSkeleton Coast Trawling

Ms PS KaulingeSkeleton Coast Trawling

Mr G KesslerSouth Namibia Hake Fishing

Ms M HlasekSouth Rock Investments cc

Ms B MathiasSouthern Namibia Hake Fishing

Mr J HallSpectrum ASA

Mr P OwensTullow Kudu Limited

Mr K StallbomTullow Kudu Limited

Mr MarinoTunacor

Mr J YounieWestbridge Energy Corp

Ms S DamensWhitefish Corporation

Mr J PretoriusrWhitefish Corporation

Mr C GraneWoker Freight Services (Pty) Ltd

Mr S ShoopalaWoker Freighting Services

APPENDIX 4.2

I&AP NOTIFICATION LETTER

1

Jeremy Blood

Subject: FW: SPECTRUM GEO LIMITED - PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE

BASIN OFF THE COAST OF NORTHERN NAMIBIA: NOTIFICATION OF AVAILABILITY

OF ENVIRONMENTAL IMPACT ASSESSMENT REPORT FOR REVIEW AND COMMENT

Attachments: Let I&APs - EIA Report Rev 2 (7 August 2017).pdf; Let IAPs - EIA Report Rev 2 (7

August 2017) AFR.PDF; Spectrum_EIR_ExecSum_only.pdf

From: Marvin Sanzila

Sent: 07 August 2017 02:14 PM Subject: SPECTRUM GEO LIMITED - PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE BASIN OFF THE COAST OF

NORTHERN NAMIBIA: NOTIFICATION OF AVAILABILITY OF ENVIRONMENTAL IMPACT ASSESSMENT REPORT FOR REVIEW AND COMMENT

Dear Sir/ Madam.

SPECTRUM GEO LIMITED - PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE BASIN OFF THE COAST OF NORTHERN

NAMIBIA: NOTIFICATION OF AVAILABILITY OF ENVIRONMENTAL IMPACT ASSESSMENT REPORT FOR REVIEW AND

COMMENT

This email provides formal notification that Spectrum Geo Limited (Pty) Ltd (“Spectrum”) has applied to undertake a

3D seismic survey in the Namibe Basin off the coast of northern Namibia under a Multi-Client Agreement with the

National Petroleum Corporation of Namibia (NAMCOR).

SLR Environmental Consulting (Namibia) (Pty) Ltd (“SLR”) has been appointed to investigate the baseline

environmental conditions to assess the potential impacts of the proposed seismic survey and present

the findings in an Environmental Impact Assessment (EIA) Report.

Notice is hereby given that the EIA Report is available for a 30-day review and comment period from 7 August to 7

September 2017.

• A copy of the full report has been made available on the SLR website (http://slrconsulting.com/za/slr-

documents/spectrum-namibia)

• A copy of the Executive Summary of the EIA Report is attached for your reference.

For comments to be included in the revised EIA Report, comments should reach SLR (contact details below) no later

than 7 September 2017.

Kind Regards

Marvin Sanzila

Marvin Sanzila

Environmental Assessment Practitioner -

+264 64 402 317

[email protected] -



House Schumacher

6 Tobias Hainyeko Street, Swakopmund, Erongo, -

ZAEXC1S

Project Reference: 7NA.19097.00003 File Ref. Spec12/Let I&APs - EIA Report Rev 2 (7 August 2017)

7 August 2017

Dear Sir / Madam

SPECTRUM GEO LIMITED - PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE BASIN OFF THE COAST OF

NORTHERN NAMIBIA: NOTIFICATION OF AVAILABILITY OF ENVIRONMENTAL IMPACT ASSESSMENT REPORT

FOR REVIEW AND COMMENT

This letter provides formal notification that Spectrum Geo Limited (Pty) Ltd (“Spectrum”) has applied to undertake a 3D

seismic survey in the Namibe Basin off the coast of northern Namibia under a Multi-Client Agreement with the National

Petroleum Corporation of Namibia (NAMCOR).

The proposed 3D seismic survey is 12 940 km2 in extent and is situated roughly between the Namibian – Angolan border

and 18º 08’ S. Water depths in the survey area range from approximately 150 m in the east to depths greater than 4 000

m in the west. The survey area is located 27 km from shore at its closest point.

SLR Environmental Consulting (Namibia) (Pty) Ltd (“SLR”) has been appointed to investigate the baseline environmental

conditions in the proposed survey area and to assess the potential impacts of the proposed seismic survey and present

the findings in an Environmental Impact Assessment (EIA) Report.

Notice is hereby given that the EIA Report is available for a 30-day review and comment period from

7 August to 7 September 2017. A copy of the full report has been made available on the SLR website

(http://slrconsulting.com/za/slr-documents/spectrum-namibia). A copy of the Executive Summary of the EIA Report is

enclosed for your reference.

For comments to be included in the revised EIA Report, comments should reach SLR (contact details below) no later

than 7 September 2017.

Should you have any queries in this regard please do not hesitate to contact the undersigned.

Yours sincerely

Marvin Sanzila

SLR CONSULTING (NAMIBIA) (PTY) LTD

Encl.

P:\Jobs\Spec13N3D\Corresp. Out\public\DEIR\Let I&APs - EIA Report Rev 2 (7 August 2017).doc


Attention: Marvin Sanzila

Schumacher House, 6 Tobias Hainyeko Street, SWAKOPMUND

Tel: +264 64 402 317; Fax: +264 64 403 327


Projekverwysing: 7NA.19097.00003 Verw. Spec12/Let I&APs - EIA Report Rev 2 (7 August 2017) AFR

7 Augustus 2017

Geagte Heer / Dame

SPECTRUM GEO LIMITED – VOORGESTELDE 3D SEISMIESE OPNAME IN DIE NAMIBE KOM LANGS DIE

NAMIBIESE NOORDKUS: KENNIS VAN BESKIKBAARHEID VAN ‘N OMGEWINGSIMPAKSTUDIEVERSLAG VIR

OORSIG EN KOMMENTAAR

Hierdie brief dien as formele kennisgewing dat Spectrum Geo Limited (Edms) Bpk (“Spectrum”) aansoek gedoen het om

‘n 3D seismiese opname in die Namibe Kom langs die noordelike kus van Namibië te onderneem onder ‘n Multi-Kliënt

Ooreenkoms met die Nationale Petroleum Korporasie van Namibië (NAMCOR).

Die voorgestelde 3D seismiese opname beslaan ‘n area van 12 940 km2 en is rowweg tussen die Namibiese grens met

Angola en 18º 08’ S geleë. Waterdieptes in die opnamegebied wissel tussen ongeveer 150 m in die ooste en dieper as

4 000 m in die weste. Die opnamegebied is by die naaste punt sowat 27 km van die kus geleë.

SLR Environmental Consulting (Namibia) (Pty) Ltd (“SLR”) is aangestel om die huidige omgewingskondisies in die

voorgestelde opnamegebied na te vors, die potensiële impakte van die voorgestelde siesmiese opname te assesseer en

die bevindinge in ‘n Omgewingsimpakstudieverslag (OIS verslag) weer te gee.

Kennis geskied hiermee dat die OIS verslag beskikbaar is vir ‘n 30-dae oorsig- en kommentaarperiode

vanaf 7 Augustus tot 7 September 2017. Die volledige verslag is beskikbaar op die SLR webblad

(http://slrconsulting.com/za/slr-documents/spectrum-namibia). ‘n Eksemplaar van die Bestuursoorsig van die OIS

verslag is vir verwysing hierby ingesluit.

Vir kommentaar om ingesluit te word in die aangepaste OIS verslag moet dit SLR (onderstaande kontakbesonderhede)

teen 7 September 2017 bereik.

U is welkom om met die ondergetekende te skakel sou u enige vrae aangaande bostaande hê.

Vriendelike groete

Marvin Sanzila

SLR CONSULTING (NAMIBIA) (PTY) LTD

Ingesl.

P:\Jobs\Spec13N3D\Corresp. Out\public\DEIR\Let I&APs - EIA Report Rev 2 (7 August 2017).doc


Aandag: Marvin Sanzila

Schumacher House, Tobias Hainyekostraat 6, SWAKOPMUND

Tel: +264 64 402 317; Faks: +264 64 403 327

E-pos: [email protected]

APPENDIX 4.3

ADVERTISEMENTS

25THE NAMIBIAN MONDAY 7 AUGUST 2017

PURPOSE OF THE JOB:Responsible for the coordinating, facilitation and day-to-day management of operations of the market, provide information to traders about procedures on how to conduct themselves in the market as well as act as a linkage between traders and council.

JOB SUMMARY:

open market.

of traders at the open market in collaboration with finance Department.

enforcement street trading regulations

23 of 1992).

conduct within the market at all times.

themselves in a safe, secure and orderly manner as per the provision of general regulations.

upon traders in case of defaults or contraventions.

its day to day activities relating to the upkeep of the market.

maintain correspondences related to the open market.

on the operations of the market

REQUIREMENTS:

added.

BENEFITS:

Pension

Transport allowance

HELAO NAFIDI TOWN COUNCIL

VACANCYProspective candidates are hereby invited to apply for the following position:

OPEN MARKET CLERK

THE CHIEF EXECUTIVE OFFICERATTENTION: THE HUMAN RESOURCES OFFICERHELAO NAFIDI TOWN COUNCIL, PRIVATE BAG 503, OHANGWENA

NB: Faxed or e-mailed applications will not be considered and only short listed applicants will be notified for interview.

CLOSING DATE: 25 AUGUST 2017

Enquiries can be directed to Mr N.A Mushaki Tel: 065- 260000

Career Opportunities at NAMIBIA AIRPORTS COMPANY

TRAINEES FIRE & RESCUE OFFICER:JOB GRADE – B3

Primary Purpose of Position:� ;V� \UKLYNV� [YHPUPUN� PU� VYKLY� [V� LUZ\YL�

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NOTICE OF ENVIRONMENTAL

IMPACT ASSESSMENT (EIA) PROCESS

PROPOSED 3D SEISMIC SURVEY OFF THE COAST OF NORTHERN NAMIBIA

Spectrum Geo Limited (Pty) Ltd (“Spectrum”) is proposing to undertake a 3D seismic survey in the Namibe Basin off the coast of northern Namibia under a Multi-Client Agreement with the National Petroleum Corporation of Namibia (NAMCOR). The purpose of this survey is to investigate the subsea geology to determine for the presence of oil and gas prospects. The proposed 3D seismic survey is 12 940 km2 in extent and is situated roughly between the Namibian – Angolan border and 18º 08’ S. Water depths in the survey area range from approximately 150 m in the east to depths greater than 4 000 m in the west. The survey area is located 27 km from shore at its closest point.

SLR Environmental Consulting (Namibia) (Pty) Ltd (“SLR”) has been appointed to investigate the baseline environmental conditions in the proposed survey area and to assess the potential impacts of the proposed seismic survey and present the findings in an Environmental Impact Assessment (EIA) Report.

Notice is hereby given that the EIA Report is available for a 30-day review and comment period from 7 August to 7 September 2017. A copy of the full report has been made available on the SLR website (http://slrconsulting.com/za/slr-documents/spectrum-namibia).

If you or your organisation wish to register as an Interested and Affected Party (I&AP) and/or wish to raise any issues or concerns regarding the proposed project, please contact Marvin Sanzila at the contact details below. For comment to be included in the revised EIA Report it should be forwarded to SLR no later than 7 September 2017.

SLR contact details:

Contact person: Marvin SanzilaAddress: Schumacher House,6 Tobias Hainyeko Street,SWAKOPMUNDTel: +264 64 402 317Fax: +264 64 403 [email protected]

Republikein18 Maandag 7 Augustus 2017Die MArk

Lobbyists’ fears that Presi-dent Donald Trump could mis handle an inquiry into

Chinese intellctual property and trade practices as he searched for ways to increase pressure on China to do more about reining in North Korea’s nuclear and missile pro-grammes, with trade policy viewed as a useful lever.

Lobbyists said Trump was right to criticize China on trade, but they expressed concern about general disorganization and inconsistency at the White House and warned that Trump might make matters worse with China if he follows through.

“Companies, I think, are rightly concerned about how this admin-istration will handle any sort of

enforcement action or investiga-tion given that we have not seen this administration be particular-ly nuanced or strategic in its ap-proach,” said a technology indus-try source who asked not to be identified because the issue is still under consideration by the White House ahead of a public announce-ment.

Trump is expected to issue a pres-idential memorandum declaring Chinese theft of intellectual prop-erty a problem that requires a US re-sponse. At the same time, US Trade Representative Robert Lighthiz-er is expected to launch an investi-gation based on Section 301 of the Trade Act of 1974.

Section 301, a popular trade tool in the 1980s that has been rarely used in the past decade, could lead to the president unilaterally slap-ping tariffs or other trade limits on China. The Section 301 process also can bypass the World Trade Organ-ization procedures for adjudicat-ing global trade grievances. Though widely used worldwide, the WTO process is viewed unfavorably by the Trump administration.

Trump’s willingness to use “ob-solete US trade law,” could create problems, said Chad Bown, a trade expert at the Peterson Institute for International Economics, a private think tank. “While the adminis-tration has identified a legitimate policy problem, Trump’s proposed

solution may only make matters worse.”

As speculation of a Section 301 probe rippled through Washing-ton, a diplomatic deal that includes China appeared to be taking shape at the United Nations on Thurs-day that would impose stronger UN sanctions against North Korea.

In addition to the United States, the European Union, Japan, Germany and Canada have all ex-pressed concern about China’s be-havior on intellectual property theft. The technology sector has been especially hard hit in IP dis-putes.

“Our members generally support trade enforcement, but want the administration to be careful those actions don’t lead to a trade war,” said an official with one business trade group, asking not to be iden-tified because the White House had not yet made an announcement.

Business lobbyists have been in talks with the White House on the issue, but some reported uncer-tainties.

“We’ve been talking with (Nation-al Security Council) but frankly for us even, it’s difficult to deter-mine exactly who are the decision makers,” the technology industry source said.

“We just don’t know exactly what the mentality will be or . . . the deci-sion making or calculus.”

– Nampa/Reuters

» Fear of trade war looming

Trump’s mishandling of China IP worrisomeUS President Donald Trump’s threat to investigate China’s intellectual property and trade practices is valid, but his administration may not be up to the delicate task of carrying out a new China probe without sparking a damaging trade war, US business lobbyists told Reuters.

Toyota, Mazda plan EV partnershipJapanese automakers Toyota Motor Corp. and Mazda Motor Corp. are partnering in electric vehicles with a deal that may lead to setting up an assembly plant in the US.

The Japanese Nikkei business daily re-ported Friday the agreement will include working toward setting up a US joint-venture plant and cooperation on elec-tric vehicle technology.

Toyota said in a statement that it plans to propose to its board a partnership with Mazda. It gave no further details.

A person briefed on the matter, who did not want to be identified because an official announcement hasn’t been made, confirmed the partnership, but no details.

President Donald Trump has been urging Toyota and other Japanese automakers to invest and build more vehicles in the US. EVs have become

an increasingly competitive market segment.

– Nampa/AP

Japanese automakers Toyota Motor Corp. and Mazda Motor Corp. are partnering in electric vehicles with a deal that may lead to setting up an assembly plant in the US. Photo NamPa/ReuteRs

A Toyota automaker employee moves an engine at the Toyota engine assembly line in Huntsville, Alabama, US. Photo NamPa/ReuteRs

KENNIS VAN OMGEWINGSIMPAKSTUDIEPROSES

VOORGESTELDE 3D SEISMIESE OPNAME LANGS DIE NAMIBIESE NOORDKUS

Spectrum Geo Limited (Pty) Ltd (“Spectrum”) stel voor om ‘n 3D seismiese opname in die Namibe Kom langs die noordelike kus van Namibië te onderneem. Die doel van die opname is om uit die subsee geologie vas te stel of daar enige olie en gasbronne is. Die voorgestelde 3D seismiese opname beslaan ‘n area van 12 940 km2 en is rowweg tussen die Namibië – Angola grens en 18º 08’ S geleë. Waterdieptes in die opnamegebied wissel van ongeveer 150 m in die ooste tot dieper as 4 000 m in die weste. Die opnamegebied is by die naaste punt sowat 27 km van die kus geleë.

SLR Environmental Consulting (Namibië) (Edms) Bpk (“SLR) is aangestel om die huidige omgewingskondisies in die voorgestelde opnamegebied na te vors, die potensiële impakte van die voorgestelde seismiese opname te assesseer en die bevindinge in ‘n Omgewingsimpakstudieverslag (OIS verslag) weer te gee.

Kennis geskied hiermee dat die OIS verslag beskikbaar is vir ‘n 30-dae oorsig- en kommentaarperiode vanaf 7 Augustus tot 7 September 2017. Die volledige verslag is beskikbaar op die SLR webblad (http://slrconsulting.com/za/slr-documents/spectrum-namibia).

Indien u of u organisasie wil registreer as ‘n Belanghebbende Party en/of u enige kwessies of bekommernisse het aangaande die voorgestelde projek, skakel asseblief met Marvin Sanzila by die onderstaande kontakbesonderhede. Vir kommentaar om ingesluit te word by ‘n aangepaste OIS verslag moet dit aan SLR gestuur word teen 7 September 2017.

SLR kontakbesonderhede:Kontakpersoon: Marvin SanzilaAdres: Schumacher House, Tobias Hainyekostraat 6, SWAKOPMUNDTel: +264 64 402 317; Faks: +264 64 403 327E-pos: [email protected] Datum van advertensie: 7 Augustus 2017

DM0201700278028 JN

APPENDIX 4.4

I&AP CORRESPONDENCE ON THE EIA REPORT

1

Jeremy Blood




From: Andrew Malherbe [mailto:[email protected]]

Sent: 31 August 2017 02:18 PM To: Marvin Sanzila

Cc: Sarah Yates Subject: RE: SPECTRUM GEO LIMITED - PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE BASIN OFF THE COAST

OF NORTHERN NAMIBIA: NOTIFICATION OF AVAILABILITY OF ENVIRONMENTAL IMPACT ASSESSMENT REPORT

FOR REVIEW AND COMMENT

Dear Marvin,

My colleague Sarah has provided a number of comments to the EIA:

1. Phytoplankton blooms are not just seasonal but also have an active and quiescent phase usually over a 10 day period,

where there is an input of nutrients during the active phase and an enhancement of primary production during the

quiescent phase of upwelling.

2. Who will ensure that seismic activities will cease if there is adverse effects to marine fauna?

3. Are there any underwater light sources? Green LED lights deter turtles (http://www.businessinsider.com/endangered-

sea-turtles-green-leds-nets-2016-3)

4. Invertebrates to large cetaceans make extensive use of underwater sounds for important biological activities (Caroll et

al., 2017):

a. Intraspecific communication

b. Predator avoidance

c. Navigation

d. Larval orientation

e. Foraging

f. Reproduction

5. High-intensity acute sounds affect cephalopods and can cause displacement, auditory damage, tissue trauma and

mortality (Caroll et al., 2017).

6. 3D seismic surveys (airgun): have predominant frequency range of seismic airgun emissions is within the detectable

hearing range of most fishes and elasmobranchs and can also elicit a neurological response in cephalopods and decapods

(Caroll et al., 2017).

Once again, thanks for getting in touch with NNF.

Regards,

Andrew.

1

Jeremy Blood




From: Beau Tjizoo [mailto:[email protected]]

Sent: 07 September 2017 05:26 PM To: Marvin Sanzila

Cc: Chris Bartholomae; Taimi Shikongo; Uatjavi Uanivi; Moses Kalola; Lavinia Nghimwatya; Titus Iilende; Chris Bartholomae; Anja Kreiner; Graca D'Almeida

Subject: RE: SPECTRUM GEO LIMITED - PROPOSED 3D SEISMIC SURVEY IN THE NAMIBE BASIN OFF THE COAST

OF NORTHERN NAMIBIA: NOTIFICATION OF AVAILABILITY OF ENVIRONMENTAL IMPACT ASSESSMENT REPORT FOR REVIEW AND COMMENT

Afternoon Marvin

I noticed that mitigation measures are proposed to minimize noise impact on marine live in the executive report.

However, the proposed “soft start” method is only applicable to large marine fauna and not known for small pelagic

fauna. Thus, I suggest that an additional measure to reduce impact on small pelagic stocks is to restrict seismic

surveys to day time within the 1000 bottom depth zone. The proposed PAM would not effectively detect small

pelagic stock and operators will not be able to see any surface activities at night.

I also think that a 9 to 10 months survey is a very long period (2/3 of a year). As alternative to your proposal of

separating seismic survey into two phases, I suggest that the survey area is divided into sections such the survey can

be conducted over a number of years (2 to 3 years) for a fixed period of a year (e.g. July to Sept) only.

Regards

Beau

APPENDIX 4.5

COMMENTS AND RESPONSES REPORT

Spectrum: Proposed 3D seismic survey in the Namibe Basin off the coast of northern Namibia:

SLR Comments & Responses Report 1

COMMENTS AND RESPONSES REPORT

NO. ISSUE

METHOD OF

COMMUNICATION

AND DATE

COMMENT RESPONSE

1. Beau Tjizoo, Ministry of Fisheries and Marine Resources

1.1 Soft-start

procedure and

night time

surveying

E-mail,

7 September 2017

I noticed that mitigation measures are proposed to

minimise noise impact on marine life in the

executive report. However, the proposed “soft

start” method is only applicable to large marine

fauna and not known for small pelagic fauna.

Thus, I suggest that an additional measure to

reduce impact on small pelagic stocks is to restrict

seismic surveys to day time within the 1 000

bottom depth zone. The proposed PAM would not

effectively detect small pelagic stock and

operators will not be able to see any surface

activities at night.

The implementation of a “soft-start” procedure is not just applicable to

large marine fauna, but also smaller fish species (see Section 5.3.3 of the

main report). Thus, a “soft-start” procedure would also allow fish to move

out of the survey area and thus avoid potential physiological injury as a

result of seismic noise.

The small pelagic purse-seine sector operates primarily northwards of

Walvis Bay to the Angolan border, inshore of the 200 m isobaths (i.e. on

the eastern boundary of the survey area). The proposed survey area

covers a very small portion (0.7%) of the fishing grounds used by the

small pelagic purse-seine fishery. Thus, the potential of impacting this

sector is considered to be highly unlikely (or improbable). In order to

avoid any unlikely interaction it is recommended that the operator engage

timeously with the fishing industry prior to and during the surveys. In this

regard, it is recommended that the fishing industry is informed of the

proposed survey activity (including navigational coordinates of the survey

area, timing and duration the proposed activities) and the likely

implications thereof (500 m safety zone and proposed safe operational

limits).

Since the implementation of a “soft-start” procedure would allow fish to

move out of the area, as well as the limited fishing activity (purse-seine)

in the area, no further mitigating is considered necessary over and above

that proposed.



NO. ISSUE

METHOD OF

COMMUNICATION

AND DATE

COMMENT RESPONSE

1.2 Survey scheduling E-mail,

7 September 2017

I also think that a 9 to 10 months survey is a very

long period (2/3 of a year). As alternative to your

proposal of separating seismic survey into two

phases, I suggest that the survey area is divided

into sections such the survey can be conducted

over a number of years (2 to 3 years) for a fixed

period of a year (e.g. July to Sept) only.

As noted, it is recommended that the survey is split into two seasons in

order to avoid the key cetacean migration and breeding period, which

extends from the beginning of June to the end of November, and if

possible until January (see Section 6.2.2 of the main report). This would

ensure that there is at least a six-month break between survey periods.

The marine fauna specialist is of the opinion that a six month break is

sufficient, and that a longer period would not make much sense.

2. Andrew Malherbe, Namibian Nature Foundation

2.1 Phytoplankton E-mail, 31 August,

2017

Phytoplankton blooms are not just seasonal but

also have an active and quiescent phase usually

over a 10 day period, where there is an input of

nutrients during the active phase and an

enhancement of primary production during the

quiescent phase of upwelling.

This comment is noted.

2.2 Termination of

surveying

E-mail, 31 August,

2017

Who will ensure that seismic activities will cease if

there is adverse effects to marine fauna?

It is recommended that an independent Marine Mammal Observer (MMO)

and a Passive Acoustic Monitoring (PAM) operator be appointed for the

duration of the seismic survey. The MMP and PAM operator will be

responsible for, inter alia, requesting the temporary termination of the

seismic survey should any adverse effect on marine fauna be observed.

The duties of the MMO and PAM operator are presented in full in Section

6.2.3.4 of the main report.

2.3 Turtles E-mail, 31 August,

2017

Are there any underwater light sources? Green

LED lights deter turtles

(http://www.businessinsider.com/endangered-sea-

turtles-green-leds-nets-2016-3).

Each tail buoy would have a light (above water) for navigational safety

reasons. The tail buoys would be fitted with turtle guards to prevent turtle

entrapment.



NO. ISSUE

METHOD OF

COMMUNICATION

AND DATE

COMMENT RESPONSE

2.4 Noise impact on

marine fauna

E-mail, 31 August,

2017

Invertebrates to large cetaceans make extensive

use of underwater sounds for important biological

activities (Caroll et al., 2017):

a. Intraspecific communication

b. Predator avoidance

c. Navigation

d. Larval orientation

e. Foraging

f. Reproduction

The potential impact of seismic noise on marine fauna is summarised in

Section 5.3 of the main report. The full Marine Faunal Assessment is

presented in Appendix 3 of the main report.

2.5 Noise impact on

cephalopods

E-mail, 31 August,

2017

High-intensity acute sounds affect cephalopods

and can cause displacement, auditory damage,

tissue trauma and mortality (Caroll et al., 2017).

2.6 Noise impact on

fish, cephalopods

and decapods

E-mail, 31 August,

2017

3D seismic surveys (airgun) have predominant

frequency range of seismic airgun emissions is

within the detectable hearing range of most fishes

and elasmobranchs and can also elicit a

neurological response in cephalopods and

decapods (Caroll et al., 2017).

APPENDIX 5

VESSEL SPECIFICATIONS

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