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Australian sea lion populations at Seal Bay and the Seal Slide (Kangaroo Island): continuation of the monitoring program

Photo: R McIntosh Report to the Department for Environment & Heritage

Wildlife Conservation Fund Project No. 3723

Simon D Goldsworthy1, Peter D Shaughnessy2, Rebecca R McIntosh3, Clarence Kennedy4, Janet Simpson4 and Brad Page1 1South Australian Research and Development Institute (SARDI), 2 Hamra Avenue, West Beach SA 5024 2South Australian Museum, North Terrace, Adelaide, SA 5000 3Zoology Department, La Trobe University, Bundoora, Victoria, 3086 4Department of Environment and Heritage, Kingscote, Kangaroo Island, SA

Australian sea lion populations at Seal Bay and the Seal Slide (Kangaroo Island): continuation of the monitoring program SD Goldsworthy, PD Shaughnessy, RR McIntosh, C Kennedy, J Simpson, B Page South Australian Research and Development Institute SARDI Aquatic Sciences 2 Hamra Avenue West Beach SA 5024 Telephone: (08) 8207 5400 Facsimile: (08) 8207 5481 http://www.sardi.sa.gov.au/ Disclaimer The authors warrant that they have taken all reasonable care in producing this report. The report has been through the SARDI Aquatic Sciences internal review process, and has been formally approved for release by the Chief Scientist. Although all reasonable efforts have been made to ensure quality, SARDI Aquatic Sciences does not warrant that the information in this report is free from errors or omissions. SARDI Aquatic Sciences does not accept any liability for the contents of this report or for any consequences arising from its use or any reliance placed upon it. Copyright South Australian Department for the Environment and Heritage and South Australian Research and Development Institute 2008. This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission from the author. Printed in Adelaide, July 2008 SARDI Aquatic Sciences Publication Number F2008/000645-1 SARDI Research Report Series No. 293 Authors: SD Goldsworthy, PD Shaughnessy, RR McIntosh, C Kennedy, J

Simpson, B Page Reviewers: J. Nichols, Ib Svane Approved by: J Tanner

Signed: Date: 11 August 2008 Circulation: Public Domain

http://www.sardi.sa.gov.au/

Table of contents 1

TABLE OF CONTENTS

TABLE OF CONTENTS...........................................................................................................1 1 EXECUTIVE SUMMARY....................................................................................................2 2 INTRODUCTION ................................................................................................................3

AIMS AND OBJECTIVES .........................................................................................................6 3 PUP PRODUCTION ESTIMATES FOR THE 2007 BREEDING SEASON AT SEAL BAY

............................................................................................................................................8 INTRODUCTION .....................................................................................................................8 METHODS.............................................................................................................................8

Field site.............................................................................................................8 Pup production estimates...................................................................................8 Cumulative births and deaths surveys................................................................8 Mark-recapture...................................................................................................9

RESULTS............................................................................................................................11 Cumulative births and deaths surveys..............................................................11 Mark-recapture estimates of pup production ....................................................11 Trends in pup abundance and pup production at Seal Bay ..............................12 Pup mortality ....................................................................................................13

DISCUSSION .......................................................................................................................19 4 PUP PRODUCTION ESTIMATES AT THE SEAL SLIDE................................................22

INTRODUCTION ...................................................................................................................22 METHODS...........................................................................................................................22 RESULTS............................................................................................................................23 DISCUSSION .......................................................................................................................23

5 MAINTENANCE OF MICRO-CHIPPING PROGRAM ........................................................27 INTRODUCTION ...................................................................................................................27 METHODS...........................................................................................................................27 RESULTS............................................................................................................................27 DISCUSSION .......................................................................................................................28

6 FUTURE OF POPULATION MONITORING AND RESEARCH PROGRAM AT SEAL BAY..........................................................................................................................................30

7 ACKNOWLEDGMENTS .....................................................................................................36 8 REFERENCES....................................................................................................................37 9 APPENDIX..........................................................................................................................41

Introduction 2

1 EXECUTIVE SUMMARY

Seals are one of the premier tourism attractions on Kangaroo Island and they underpin a

regional multimillion dollar tourism industry. Its centrepiece is the Australian sea lion

population at Seal Bay Conservation Park. The aims of this project were to ensure that

continuity in monitoring of the Seal Bay Australian sea lion population be maintained, until

the resources required to implement an ongoing research and monitoring program can be

secured.

Pup production for the 2007 breeding season at Seal Bay was estimated to be 260 (± 95%

CL 254-272), based upon a range of methods including, twice-weekly surveys of new pup

births and deaths, the total number of tagged (micro-chipped) pups, mark-recapture methods

using the Petersen estimate and surveys of pups in Pup Cove.

A survey was also undertaken of pup production at the Seal Slide population of Australian

sea lions using a capture-mark and count method in conjunction with the Petersen estimate.

The estimate of pup production for the 2007 breeding season at this colony was 16 (± 95%

CL15-18).

This report provides additional evidence of the ongoing decline in the Seal Bay Australian

sea lion population. The current rate of this decline is estimated to be between 3.3-4.5% per

18 month breeding season. This rate of decline would see the population more than halve

within 24-32 years. Although there is corroboration in this result from the estimates of pup

production over the last four breeding seasons and from a model of the Seal Bay population,

both the time-series of pup production estimates and the demographic factors upon which

the population model were developed are limited. As such there is a high degree of

uncertainty in the actual and current rates of decline, and in the expected trajectory of the

population into the near future. This provides significant challenges for State and

Commonwealth threatened species managers, managers of the Seal Bay Conservation

Park, and the Kangaroo Island regional tourism industry.

The absence of ongoing funding to support a population monitoring and research program

remains a critical issue for the future management and sustainability of Seal Bay. Such

support is needed to ensure that the status and health of the population is adequately

monitored; that the population decline is arrested; and that threatening processes are

identified, monitored and managed.

Introduction 3

2 INTRODUCTION

Background The Australian sea lion (ASL), Neophoca cinerea, is one of five sea lion species in the world.

Sea lions form around one-third of species in the Otariidae family of seals that includes all of

the fur seals and sea lions. Over recent decades there has been growing concern over the

status of all five sea lion species. In the North Pacific Ocean, the Steller sea lion, Eumetopias

jubatus, has been declared endangered in parts of its range and is considered threatened

with extinction in other parts (Trites et al. 2007). Although the total population of California

sea lions in California and Mexico is increasing (Caretta et al. 2004), the Mexican stock is in

decline (Szteren et al. 2006). There have also been reductions in numbers of the Galapagos

subspecies of the Californian sea lion, Zalophus californianus wollebaeki (Alava and Salazar

2006), and the Japanese subspecies, Z. c. japonicus, is possibly extinct (Mate 1982).

Numbers of South American sea lions, Otaria flavescens, have declined considerably in

recent years (Crespo and Pedraza 1991, Reyes et al. 1999, Shiavini et al. 2004), especially

in the Falkland Islands (Thompson et al. 2005), and numbers of New Zealand sea lions,

Phocarctos hookeri (Lalas and Bradshaw 2003), and ASL (McKenzie et al. 2005) have not

recovered from historic sealing, and form the smallest populations of all sea lion species.

Australian sea lions were listed as a threatened species under the Environment Protection

and Biodiversity Conservation (EPBC) Act in February 2005. In South Australia, they were

listed in February 2008 as Vulnerable under the National Parks and Wildlife Act of 1972.

Recently the Pinniped Specialist Group of the IUCN have upgraded the listing of Australian

sea lions to the endangered category.

The ASL is Australia’s only endemic and least-abundant seal species. It is unique among

pinnipeds in being the only species that has a non-annual breeding cycle (Gales et al. 1994).

Furthermore, breeding is temporally asynchronous across its range (Gales et al. 1994, Gales

and Costa 1997). It has the longest gestation period of any pinniped, and a protracted

breeding and lactation period (Higgins and Gass 1993, Gales and Costa1997). The

evolutionary determinates of this atypical life-history remain enigmatic. Recent population

genetic studies have indicated little or no interchange of females among breeding colonies,

even those separated by short (20 km) distances (Campbell 2003, Campbell 2008). The

important management implication of extreme levels of female natal site-fidelity (philopatry)

is that each colony effectively represents a closed population.

There are 73 known breeding locations for ASLs, 47 of which occur in South Australia (SA)

where the species is most numerous (80% of pups counted), with the remainder (26

Introduction 4

colonies) in Western Australia (McKenzie et al. 2005). The species was subject to sealing in

the late 18th, the 19th and early 20th centuries, resulting in a reduction in overall population

size and extinction of populations in Bass Strait and other localities within its current range.

Total pup production for the entire species during each breeding cycle has been estimated at

about 2,500 with an estimated overall population size based on a demographic model

developed by Goldsworthy et al. (2003), of around 9,800 (McKenzie et al. 2005). A re-

analysis of this demographic model, in conjunction with improved estimates of pup

production for some sites, increased pup production estimates for SA to 2,674 (10,905

individuals) (Goldsworthy and Page 2007). With more recent estimates for The Pages

(Shaughnessy and Goldsworthy 2007), Olive Island (Goldsworthy et al. 2007a) and

Dangerous Reef (Goldsworthy et al. 2007b), pup production in SA is now estimated at 3,087

per breeding cycle with a total population size of 12,959 individuals, using a pup production

to total population multiplication factor of 4.08 developed by Goldsworthy and Page (2007).

Adding to this the pup production estimate of 706 for WA sites (Goldsworthy et al. 2003), the

total pup production for the species is currently estimated at about 3,793 per breeding cycle,

with an overall population estimate of around 15,475.

There are 39 ASL breeding sites in SA, when the criterion for classification as a breeding

colony is set at ≥ 5 pups present per breeding cycle (McKenzie et al. 2005, see Fig. 2.1). Of

these, only eight (21%) produce more than 100 pups, and these account for 66% of the

State’s pup production. The largest population is Dangerous Reef in Southern Spencer Gulf

(709 pups from 2007 survey, Goldsworthy et al. 2007b), followed by The Pages (North and

South Page Islands combine, 589 pups from 2005 survey; Shaughnessy and Goldsworthy

2007) in Backstairs Passage between Kangaroo Island and mainland Australia. The next

largest populations are Seal Bay (260 pups from the 2007 survey in this report) on Kangaroo

Island, West Waldegrave (157 pups; Shaughnessy et al. 2005) and Olive Islands (206 pups;

Goldsworthy et al. 2007a) off the west coast of the Eyre Peninsula, and Purdie Island in the

Nuyts Archipelago (132 pups; Goldsworthy et al. in review). The median pup production for

SA is 27 per colony, with 60% of breeding sites producing fewer than 30 pups per season, 42

% fewer than 20 pups, and 13% fewer than 10 pups (Goldsworthy and Page 2007). These

analyses do not take into account at least another 11 breeding sites (termed ‘haul-out sites’

with occasional pupping), where fewer than 5 pups have been recorded at some time

(McKenzie et al. 2005).

There are two main ASL colonies on Kangaroo Island; Seal Bay situated on the south coast

in the Seal Bay Conservation Park, and the Seal Slide situated on the south-east coast of the

Cape Gantheaume Conservation Park (Figure 2.1). Seal populations on Kangaroo Island

Introduction 5

form the basis of a valuable tourism industry, worth an estimated $72 million in 2001.

Approximately 150,000 visitors come to the island each year (Kangaroo Island Tourism

Optimisation Management Model (TOMM) Annual Report 2004-2005,

http://tomm.info/reports_factsheets/annual_reports.aspx), most (~110,000) visit Seal Bay

Conservation Park (referred to as Seal Bay hereon) and Flinders Chase National Park for

opportunities to view populations of ASL and New Zealand fur seals (Arctocephalus forsteri).

As a consequence, observing wildlife forms the main activity of tourists on the island,

involving 82% of all tourists surveyed in 2005/06, with 78% visiting Seal Bay (KI TOMM

Visitor Exit Survey Report 2005/2006,

http://tomm.info/media/contentresources/docs/TOMM_VES_2005-2006_FinalReport.pdf).

At Seal Bay, for the 13 pupping seasons between 1985 and 2002-03, analysis of data for the

maximum count of live pups each season showed an annual decrease of 0.77% per year, or

1.14% per breeding cycle, which amounted to a decrease of 12.6% for the period

(Shaughnessy et al. 2006). The average count of live pups for that period was 144 per

season. By including the highest live pup counts for the next two seasons, 2004 and 2005-

06, McIntosh (2007) showed that the general decline was still apparent, although less than

that reported by Shaughnessy et al. (2006) at 0.69% per year. In three recent breeding

seasons (2002-3, 2004, 2005-06), pup production has also been estimated by mark-

recapture, which gives a better estimate of abundance than direct counting. These estimates,

that included cumulative dead pups and an estimate of the number of pups in Pup Cove

(outside the mark-recapture area), were on average 1.28 times greater than the best

estimates based upon direct counts of live and dead pups (McIntosh 2007). However,

because of access restrictions to the Eastern Prohibited Area (EPA), accurate counts of

births and deaths there made it difficult to meet all the assumptions of the mark-recapture

estimates (McIntosh 2007). Given this and physical limitations on access to Pup Cove, there

is still uncertainty about the accuracy of these recent surveys of pup production.

Given the uncertainties in historic pup abundance data, McIntosh (2007) developed a

demographic model based upon tagged and micro-chipped seals, to provide estimates of

survival, recruitment, fecundity and longevity. The most conservative model produced that

was most representative of the Seal Bay population, estimated the population to be declining

by 4.5% per breeding season, much greater than the rate detected based upon live pup

counts. This rate of decline would see the population more than halve within 26 years (~17

breeding seasons) (McIntosh 2007).

Introduction 6

Aims and Objectives

The monitoring that has been achieved at Seal Bay of the ASL population over the last three

breeding seasons, has been largely dependent on a PhD program undertaken by one of us

(RM), for which the field program has now been completed. There have been a number of

discussions between DEH managers, researchers and other stakeholders in recent years, all

of which have identified the need to have a fully funded research and monitoring program to

address population management needs. In response to this, Goldsworthy et al. (2007c)

recently reported on ‘A population management and monitoring program for the Seal Bay

(Kangaroo Island) Australian sea lion population’ that details the research and monitoring

needs (and costs) to support management of the Australian sea lion population at Seal Bay

on Kangaroo Island.

Given the recent listing of the species as Threatened, the current decline in the Seal Bay

population, its iconic status and importance to the regional economy, it is critical that an

annual research and monitoring program be implemented. The aims of this project were to

ensure that continuity in monitoring of the Seal Bay population is maintained, and undertake

the absolute minimum required to maintain the monitoring program until the resources

required to implement an ongoing research and monitoring program are secured.

The aims of this study were therefore to:

a) Assess Australian sea lion pup production and mortality by direct counting and mark-

recapture methods at Seal Bay and the Seal Slide colonies on Kangaroo Island during the

2007 breeding season (Apr-Nov), and

b) Maintain the tagging (micro-chipping) and monitoring program to monitor annual changes

in survival and recruitment in the population.

Format of the report The report has four main sections: Chapters 3 and 4 detail pup production estimates for Seal

Bay and the Seal Slide for the 2007 breeding season. Chapter 5 details the results from

micro-chipping of pups for the 2007 season and Chapter 6 discusses and makes

recommendations for support for an ongoing research and monitoring program.

Introduction 7

Figure 2.1 Location of Seal Bay and the Seal Slide on Kangaroo Island, relative to other Australian sea lion colonies in South Australia.

Pup Production Estimates at Seal Bay 8

3 PUP PRODUCTION ESTIMATES FOR THE 2007 BREEDING SEASON AT SEAL BAY

Introduction

This chapter details methods and presents results of estimates of Australian sea lion pup

production at Seal Bay during the 2007 breeding season.

Methods

Field site

Seal Bay is part of the Seal Bay Conservation Park situated on the south coast of Kangaroo

Island, centred on 35.996 S, 137.327 E. The sea lion colony comprises four main areas

(Figure 3.1) that are referred to as Pup Cove (2 km west of the visitor centre), the Western

Prohibited Area (WPA), Main Beach (MB), including the sand dunes and swales inland from

MB and the scrub behind the swales (referred to as the Road Reserve), and the Eastern

Prohibited Area (EPA). Limestone promontories separate the WPA and EPA from MB. Most

pups are born in the WPA and at the western end of MB with smaller numbers of pups born

in Pup Cove, inland from the WPA and MB, in the dunes behind the eastern end of MB, and

in the EPA (McIntosh 2007). The WPA and EPA were declared in 1972 under the National

Parks and Wildlife Act, 1972 (SA Government Gazette, December 7, 1972, pp. 2543-2544)

for the “purposes of conserving the native animals on that portion of the Seal Bay

Conservation Park described”.

Pup production estimates

Two methods were used to estimate pup production at Seal Bay during the 2007 breeding

season: the cumulative survey of new births and deaths throughout the colony; and mark

recapture methods using the Petersen estimate (Seber 1982).

Cumulative births and deaths surveys

Between 30 May and 30 December 2007 a total of 54 surveys of the Seal Bay colony were

undertaken. For most of this period (30 May to 28 November), surveys were undertaken

about twice weekly (mean interval = 3.6 days, SD = 1.7, n = 51). Surveys were conducted

throughout the entire breeding areas of the Seal Bay colony, including Pup Cove (2 km west


of the visitor centre), the Western Prohibited Area (WPA), Main Beach, including the sand

dunes and swales inland from Main Beach and the scrub behind the swales (referred to as

the Road Reserve), and the Eastern Prohibited Area (EPA, including Bays 3, 4 and 5, Figure

3.1). All areas could be searched thoroughly, with the exception of Pup Cove, which cannot

be accessed safely. However, much of Pup Cove where sea lions haul-out and breed can be

viewed from several vantage points along the cliff above the cove, which enables new born

pups with attending females and mate-guarding males to be detected.

When Australian sea lion females give birth, they remain with their pup during the peri-natal

period, which lasts between 7-10 days, during which time they are usually mate-guarded by

an adult male. The frequency of surveys undertaken throughout the breeding season

ensured that all new births that occurred would be detected by the presence of attending

females and mate-guarding males. The location of all new births was recorded. The

cumulative number of births recorded for each part of the colony was summed to provide an

estimate of pup production for the entire Seal Bay colony. Between surveys, increases in

cumulative new births were used to calculate the median pupping dates following the

modified probit analysis of Caughley (1977).

In addition to new births, all new pup deaths that had occurred since the previous visit were

also recorded. To avoid double counting, dead pups were sprayed with paint or covered with

rocks when they were counted.

Mark-recapture

As part of an on-going population demography study at Seal Bay, pups were marked

externally by clipping the fur of the rump and also micro-chipped by implanting Passive

Integrated Transponder tags (PIT tags: TIRIS™ RFID 23mm, sterile single-use needle)

subcutaneously. This procedure was only undertaken when pups were at least two months of

age. Pups were captured by hand when unattended by their mother. Clip marks were visible

on pups up until the end of the breeding season. As the number of marked animals in the

population increased, mark-recapture procedures were used to estimate the number of live

pups in the Seal Bay colony. Mark-recapture surveys were incorporated into the colony

surveys conducted between 11 September and 30 December 2007, and included all areas

with the exception of Pup Cove.

During each survey of the colony, the number of marked and clear pups was recorded, taking

care not to double count individuals. On most surveys the identity of marked pups was

determined by scanning with a hand-held RFID PIT tag reader.


Mark-recapture estimates of pup numbers ( ) were calculated using a variation of the

Petersen method (formula attributed to D.G. Chapman by Seber 1982), with the formula

N̂

1)1(

)1)(1(ˆ −+

++=

mnMN ,

where M is the number of marked pups at risk of being sampled during recapture operations

(based on the number of pups given clip-marks/micro-chips to date), n is the number of pups

examined in the recapture sample, and m is the number of marked (clipped/micro-chipped)

pups in the recapture sample.

The variance of this estimate is calculated as

)2()1())()(1)(1()ˆvar( 2 ++

−−++=

mmmnmMnMN

.

Where several mark-recapture estimates ( ) are undertaken (one from each recapture

session), they are combined by taking the mean (N) using formulae from White and Garrott

(1990, pp. 257 & 268):

jN̂

∑=

=q

j

j

qN

N1

ˆ

where q is the number of estimates for the colony (i.e., the number of recapture sessions).

The variance of this estimate is calculated from

)ˆ(var1)var(1

2 j

q

jN

qN ∑

=

= .

Following Kuno (1977), the square root of var(N) gives the standard error (SE) for the

estimation, and the 95 % confidence limits calculated as

. )*96.1( SEN ±

As mark-recapture surveys were made throughout the breeding season, individual surveys

estimated the number of pups alive in the colony on a given day. In order to use these data to

provide multiple estimates of total pup production, individual survey estimates were adjusted

as follows:

jj

q

jjjj PCbbdNAdjN −⎟⎟

⎠

⎞⎜⎜⎝

⎛−++= ∑∑∑

=1

ˆ


Where AdjNj is the adjusted total estimate of pup production for each (jth) survey, ∑dj is the

cumulative number of dead pups counted up to the jth survey, ∑b is the cumulative number

of new pups observed during the breeding season, ∑bj is the cumulative number of new pups

counted up to the jth survey and PCj is the number of pups counted in Pup Cove on the jth

survey. In this way multiple estimates of total pup production could be made and a mean

(AdjN), and 95% confidence limits calculated as detailed above.

Results

Cumulative births and deaths surveys

A summary of the birth and death surveys undertaken during the 2007 breeding season at

Seal Bay is presented in Table 3.1. Details of all the survey results for each area within the

colony are given in Appendix 1. The breeding season lasted seven months, commencing in

May and ending in December. 90% of births occurred over 120 days (3.9 months), between

28 June and 26 October (Table 3.2). The median pupping date was 27 August (sd = 36 days)

(Table 3.2). The mean interval in median pupping date between four consecutive breeding

seasons was 542.7 days (range 541-545, sd = 2.1, n = 3), or 17.8 months (based on the

median pupping dates in Table 3.2).

The cumulative number of births recorded for the 2007 breeding season at Seal Bay was 245

(Table 3.1, Figure 3.1). Most pups were born in the Main Beach area (97, 39.6%) (outside

public access), and the WPA (63 pups, 25.7%), with 47 pups reported for the EPA (19.2%)

and 38 pups for Pup Cove (15.5%)(see Appendix 1). As Pup Cove could only be surveyed

from along the cliff-line at various vantage points above the Cove, the number of cumulative

births there may be under estimated.

Of the 245 births, 51 (20.8%) were reported dead by the end of the breeding season (Table

3.1). The highest live pup count was 145 on 3 November 2007 (Table 3.1, Figure 3.1).

Mark-recapture estimates of pup production

Details of 29 mark-recapture Petersen estimates are provided in Table 3.1. For the AdjN

values (estimates of total pup production), estimates ranged between 222 and 338 (Table

3.1, Figure 3.1). There was little pattern to this variability, with the exception that between 8

November and 30 December, estimates were consistently high. This may have been due to


temporary dispersal of large (marked) pups away from the survey area, reducing the

percentage of marked pups in recapture samples, and hence producing higher than expected

(biased) Petersen estimates. These six recapture estimates, and the first two estimates (on

11 and 16 September, that were based on only 9 marked pups in the population) were

omitted, leaving 21 recapture estimates to calculate the Adj N estimate of total pup

production. The estimate of pup production based on this approach was 260 (with 249-271

95%CL) (Table 3.1 and 3.2). This is 15 more pups than that estimated from the cumulative

survey of new births. These additional pups are likely to be uncounted pups from Pup Cove

that were not able to be observed from the cliff-top vantage points. For the 21 mark-

recapture estimates used, there was no significant relationship between the estimate and

date of the survey (F1,20=1.259, P = 0.276).

Following the breeding season, an additional 27 pups were micro-chipped up until 12 May

2008, giving a total of 203 micro-chipped pups (Chapter 5). Adding this total to the cumulative

dead pups (51 all non-micro-chipped), gives a minimum estimate of pup production (total

micro-chipped + cumulative dead) of 254, 6 less than estimated from Adj N (Table 3.2). This

minimum estimate enables the lower confidence limit of Adj N to be increased slightly, giving

a final estimate of pup production for the 2007 breeding season at Seal Bay of 260 (254-272

95%CL).

Trends in pup abundance and pup production at Seal Bay

The surveys undertaken during the 2007 season at Seal Bay represent the fourth

consecutive breeding season when mark-recapture procedures have been used to provide

Petersen estimates of pup production. Comparison of the timing of breeding, estimates of

pup production, highest live pup counts and cumulative births and pup deaths between these

four breeding seasons are given in Table 3.2. In addition, trends in live pup counts between

1985 and 2007 (16 breeding seasons), and Petersen estimates of pup production and

mortality rates of pups between 2003 and 2007 are presented in Figure 3.2.

As detected by Shaughnessy et al. (2006), an examination of the trends in maximum live pup

counts between 1985 and 2007 identified an apparent oscillation in pup numbers between

high and low seasons (Figure 3.2). Following the approach of Shaughnessy et al. (2006),

trends in maximum live pup counts were analysed using a general linear model (GLM)

incorporating backwards stepwise inclusion of the three predictor variables (year, inter-

breeding interval and their interaction, with probability P set at 0.15 to enter or remove a

predictor) which produced a significant model that included all predictor variables (F3,12 =

5.407, P = 0.014, r2 = 0.575). As detected by Shaughnessy et al. (2006) for the 1985 to


2002-03 analysis, results indicate that year, inter-breeding interval and the interaction

between year and interval, all significantly contribute to explaining variance in the numbers of

pups counted at Seal Bay over the 16 consecutive breeding season between 1985 and 2007.

The negative coefficients of the terms indicate that both year and inter-breeding interval have

a significant negative effect on the maximum numbers of live pups counted.

Trend analyses in maximum live pup counts for the 16 pupping seasons between 1985 and

2007, demonstrated an annual decrease of -0.54% per year, or -0.78% per breeding cycle,

which amounted to a decrease of -11.1% over the 16 year period.

Examination of the four consecutive breeding season estimates of pup production based on

mark-recapture and Petersen estimates, supports the same oscillation in pup numbers

between high and low pup production seasons observed above, with 2002-03 and 2005-06

being low pup production years and 2004 and 2007 being high pup production years. There

is also a general decline in pup numbers between the two successive low and high pup

production breeding seasons (Table 3.2, Figure 3.2). The rate of decline in pup production

between these successive low and high pup production seasons was -1.8% and -4.9% per

breeding season (mean -3.3%), or between -1.2% and -3.3% per year, respectively (mean -

2.3%).

Pup mortality

Based on a pup production estimate of 260 pups for the 2007 breeding season at Seal Bay,

and a total of 51 cumulative pup deaths, the mortality rate for the breeding season was

estimated to be 19.6% (Table 3.2). This compares to 32.2% for 2002-03, 24.3% for 2004 and

34.2% for the 2005-06 breeding season, an average of 27.6% (sd = 6.8) over the four

seasons (Table 3.2). Mortality rate appears to oscillate between high and low seasons and

vary inversely with estimated pup production (r2=0.63), although not significantly (F1,2=3.40,

P=0.206, Figure 3.2).

14

Figure 3.1 Map of Seal Bay breeding colony, Kangaroo Island, extended to Bay 2 (EPA 2), of the Eastern Prohibited Area (EPA). Western Prohibited Area (WPA), Main Beach and EPA comprise the main areas of the site.

Pup Production Estimates at Seal Bay


Table 3.1 Summary of surveys undertaken for new births and dead pups, cumulative births and deaths, and counts of brown (BP), moulted (MP) and total live Australian sea lion pups at Seal Bay during the 2007 breeding season. Details of Petersen mark-recapture estimate are also given, where N refers to total estimate of live and cumulative dead pups and counts in Pup Cove on the day of survey, Adj N is the same as N but includes the remaining new births to occur in the population. The shaded values are those used to calculate mean Adj N (and its 95% CL).

Date New New Cumulative Counts Petersen M-R estimates

No. Births Dead Born Dead Alive BP MP Total live M n m N Adj N SE

1 30-May 1 0 1 0 1 0 0 1 2 6-Jun 1 0 2 0 2 1 0 1 3 12-Jun 0 0 2 0 2 1 0 1 4 15-Jun 1 1 3 1 2 2 0 2 5 19-Jun 2 0 5 1 4 3 0 3 6 21-Jun 1 1 6 2 4 3 0 3 7 26-Jun 3 0 9 2 7 6 0 6 8 29-Jun 3 0 12 2 10 10 0 10 9 5-Jul 1 0 13 2 11 9 0 9

10 11-Jul 11 3 24 5 19 19 0 19 11 13-Jul 4 0 28 5 23 21 0 21 12 18-Jul 4 3 32 8 24 18 0 18 13 24-Jul 17 5 49 13 36 31 0 31 14 26-Jul 9 0 58 13 45 35 0 35 15 30-Jul 7 1 65 14 51 38 0 38 16 3-Aug 12 1 77 15 62 45 0 45 17 7-Aug 8 0 85 15 70 50 0 50 18 10-Aug 7 0 92 15 77 52 0 52 19 13-Aug 8 1 100 16 84 58 0 58 20 17-Aug 9 1 109 17 92 61 0 61 21 22-Aug 10 3 119 20 99 65 0 65 22 28-Aug 12 2 131 22 109 71 0 71 23 31-Aug 14 5 145 27 118 88 0 88 24 4-Sep 7 0 152 27 125 85 0 85 25 7-Sep 4 1 156 28 128 94 0 94 26 11-Sep 17 3 173 31 142 95 0 95 9 81 4 163 280 45.9 27 16-Sep 6 0 179 31 148 108 0 108 9 93 5 156 268 36.2 28 20-Sep 16 4 195 35 160 107 0 107 18 88 9 168 272 33.1 29 24-Sep 12 2 207 37 170 102 0 102 24 80 9 202 299 44.3 30 26-Sep 1 0 208 37 171 96 0 96 27 80 10 205 295 43.1 31 27-Sep 3 0 211 37 174 109 0 109 27 92 15 162 250 23.5 32 28-Sep 1 0 212 37 175 124 0 124 34 112 19 197 279 25.6 33 1-Oct 2 1 214 38 176 111 0 111 36 98 17 203 285 30.3 34 2-Oct 1 0 215 38 177 100 0 100 38 84 21 150 234 17.9 35 3-Oct 3 1 218 39 179 97 0 97 42 82 19 177 258 24.8 36 5-Oct 4 1 222 40 182 108 0 108 45 94 20 207 284 28.9 37 8-Oct 2 2 224 42 182 108 0 108 47 94 17 252 329 41.4 38 12-Oct 3 0 227 42 185 105 0 105 47 95 22 199 269 25.7 39 15-Oct 0 0 227 42 185 93 0 93 47 84 19 203 272 29.7 40 17-Oct 1 0 228 42 186 120 1 121 47 104 32 152 228 12.1 41 18-Oct 0 0 228 42 186 138 1 139 47 124 36 161 235 10.6 42 19-Oct 0 0 228 42 186 136 0 136 47 119 33 168 244 13.1 43 22-Oct 3 2 231 44 187 94 0 94 47 87 23 175 240 21.2 44 26-Oct 1 0 232 44 188 84 0 84 47 72 17 194 263 30.6 45 29-Oct 2 0 234 44 190 94 0 94 57 85 28 171 235 18.1 46 30-Oct 0 0 234 44 190 127 0 127 68 119 37 217 280 19.3 47 1-Nov 1 0 235 44 191 111 0 111 80 99 47 168 234 11.1 48 3-Nov 1 0 236 44 192 154 0 154 92 136 70 178 249 7.1 49 8-Nov 0 0 236 44 192 88 0 88 96 85 31 260 316 29.4 50 15-Nov 2 2 238 46 192 105 0 105 101 99 40 248 307 22.8 51 22-Nov 2 0 240 46 194 109 1 110 101 101 32 314 374 36.6 52 28-Nov 3 3 243 49 194 95 2 97 124 93 44 260 315 22.2 53 21-Dec 1 1 244 50 194 77 1 78 176 77 54 250 302 15.1 54 30-Dec 1 1 245 51 194 116 8 124 176 123 77 280 332 14.4

Mean Adj N 260 5.9 (95% CL 249-272)


Table 3.2 Summary of the timing and spread of four consecutive Australian sea lion breeding seasons at Seal Bay, and pup abundance estimates including: cumulative births and pup deaths; maximum live pup count; total numbers of micro-chipped pups and minimum pup production (micro-chipped + cumulative pup deaths); adjusted mark-recapture Petersen estimates (Adj N); and the overall estimate of pup production. Estimated mortality rate is also included. Comparative data for the 2002-03, 2004 and 2005-06 breeding seasons are from McIntosh et al. (2006) and McIntosh (2007), unless otherwise indicated.

2002-03 2004 2005-06 2007

Month breeding season commenced Dec-02 Jun-04 Dec-05 May-07

Duration of breeding season (months) 9 7 6 7

Median pupping date 13-Mar-03 5-Sep-04 28-Feb-06 27-Aug-07

± s.d. (days) 42 39 36 36

90% births (5%- 95%) 2 Jan—21 May1 3 Jul -1 Nov 4 Jan-18 Apr 28 Jun- 26 Oct

90% births (days) 1391 121 104 120

Cumulative births - 200 207 245

Cumulative pup deaths 73 70 75 51

Maximum live pup count 122 148 125 145

At months since beginning of BS 6 7 6 6

Max live pup count + cumulative dead2 185 208 197 198

Total live pups micro-chipped 148 202 144 203

Minimum pup production3 221 272 219 254

Adj N 227 288 203 260

( 95% CL) (216-239) (273-302) (199-207) (249-272)

No. recapture estimates 3 2 3 21

Overall estimate of pup production 227 288 219 260

Confidence limit (min est. to 95% CL) (221-239) (273-302) (254-272)

Mortality rate 32.2% 24.3% 34.2% 19.6%

1Shaughnessy et al. 2006 2at time of maximum live count 3total micro-chipped + cumulative dead


Figure 3.1 Changes in the number of cumulative pup births, deaths, minimum alive, and number of live pups counted during twice weekly surveys of Australian sea lion pups at Seal Bay between 30 May and 30 December 2007. Values of Adj N (± SE) are also given.


Figure 3.2 Trends in the abundance of Australian sea lion pups at Seal Bay based on maximum live pup counts, for 12 breeding season between 1985 and 2007. Trends in the estimated total pup production (based on Adj N mark-recapture estimates, with 95% CL) and pup mortality rate are also presented.


Discussion The 2007 survey at Seal Bay is the fourth consecutive breeding season at Seal Bay where

‘modern’ methods have been used to estimate total pup production. Between 1973-74 and

2002-03 (20 breeding seasons), maximum counts of pups during each breeding season

where used to provide an index of pup abundance (reviewed by Shaughnessy et al. 2006).

The introduction of modern survey methods in the 2002-03 breeding season using mark-

recapture techniques, identified that visual counts of pups may only census a little over half of

those actually present (McIntosh et al. 2006). Additional mark-recapture surveys undertaken

in the 2004 and 2005-06 breeding seasons reinforced this pattern, with mark-recapture

surveys averaging 1.58 times those of visual counts (range 1.10 to 2.05, McIntosh 2007).

Given the large variance in the correcting factor between estimated and counted pups, the

degree of confidence that can been placed in trend analyses using count data is questionable

(Shaughnessy et al. 2006).

Modern censusing methods are not free from problems either. McIntosh (2007) identified that

although results from the 2002-03 and 2004 mark-recapture surveys satisfied the

assumptions of equal capture and recapture probability, the 2005-06 results did not,

questioning the accuracy of the latter survey estimates. Access restrictions to parts of the

colony at Seal Bay, were considered to be the most likely cause for violating the assumption

of the Petersen estimate (McIntosh 2007). The physical access restrictions to Pup Cove with

its steep limestone cliffs were not considered a major problem. Because pups leave Pup

Cove to join the rest of the colony when old enough, and movement of pups is only from west

to east, lack of access could be corrected for by excluding the area from the mark-recapture

survey and adding a direct count of pups remaining in Pup Cove onto the mark-recapture

survey result. However, lack of access to the EPA as a consequence of site management

and Local Area Policy, meant that pups were not captured and marked evenly throughout the

colony. Although there is some movement of pups between the EPA and other areas of the

colony, the ratio of marked pups to unmarked pups was lower in the EPA at the time of the

mark-recapture surveys compared to the Main Beach and WPA areas, and this may have led

to a failure to meet the assumptions of mark-recapture in the 2005-06 breeding season

(McIntosh 2007). In this season the cumulative birth count and total number of micro-chipped

pups plus cumulative dead pups also exceeded the mean estimate of pup production based

on mark-recapture methods (McIntosh 2007).

Access restrictions to the EPA were lifted for the 2007 breeding season, and although testing

for the assumption of equal capture and recapture probability was beyond the scope of this

study (although data are available to test for this), we expect the assumptions were satisfied


because, with the exception of Pup Cove, the marking and survey efforts for the remainder of

the colony were consistent during the breeding season. Overall, there has been a

progressive improvement in the application of the modern survey methods over the past four

breeding seasons at Seal Bay, with the 2007 survey providing the most supported estimate

(cumulative births ~94% Adj N). Further, due to very comprehensive efforts to micro-chip

pups following the breeding season, the combined estimate of pups based on the addition of

micro-chipped and cumulative dead pups was only 6 less (98.5%) than the Adj N estimate of

pup production.

If it were not for the physical access restrictions into Pup Cove, cumulative birth counts (if

undertaken at least twice-weekly throughout the breeding season), would provide the best

means of estimating pup production. Based on Petersen estimates during the 2007 breeding

season, about 15 additional births to those reported occurred; most of these were likely to

have occurred in obscured parts of Pup Cove. As such, the Petersen estimate provides an

important check against estimates of pup production based upon cumulative new births, and

importantly provides confidence limits around estimates. Further, by being able to report on

the physical location and timing of almost all births in the population, the twice-weekly

surveys also provide an accurate means to monitor the timing and duration of pupping, and

importantly to accurately determine rates of mortality throughout the breeding season.

Despite improvement in estimating pup production at Seal Bay, there is still some uncertainty

in the degree to which the survey of pup production throughout the breeding season using

mark-recapture, meets all the assumptions of the Petersen estimate. The five assumptions

are that: i) every animal, marked and unmarked, must have the same probability of capture

and recapture; ii) animals must be marked uniformly throughout the survey area; iii) every

animal must have the same probability of mortality or of leaving the sampling area for the

duration of the experiment; iv) marks must not be lost and must be correctly reported; and v)

no animal is born or immigrates to the study area between marking and recapturing

(Caughley 1977; Seber 1982). Most of these assumptions have been assessed by McIntosh

(2007). Most uncertainty surrounds assumption iii). Because of the extended breeding

season, pup age can vary by between 6-9 months within each breeding season. Younger

pups are less mobile and less likely to leave the colony area, have a greater probability of

mortality (McIntosh 2007) and are less likely to be marked compared to older pups (pups are

marked when older than two months). As such, the likelihood of re-sighting younger and

unmarked pups is likely to be greater than for older and marked pups, and therefore they

have different likelihoods of re-sightability and mortality (McIntosh 2007). This may explain

progressive changes in the estimates of adjusted N throughout the 2007 breeding season,


with greater dispersal of larger (marked) pups away from the survey area towards the end of

the breeding season, leading to a reduction in the percentage of marked pups in recapture

samples and higher than expected estimates (Figure 3.1). Further research needs to be

undertaken to assess the importance of differences in the recapture probabilities relating to

age, mortality and marking to the assessment of pup production using the Petersen estimate.

Despite these remaining challenges, three factors have improved the accuracy and precision

of pup production estimates at Seal Bay: the removal of access restrictions to the EPA for

pup surveys, multiple mark-recapture estimates undertaken throughout the breeding season

and increased micro-chipping efforts.

Trends in pup production

The 2007 survey provides additional support for the continuing decline in pup production and

population size at Seal Bay. Based upon three more seasons of maximum live pup counts

from those reported by Shaughnessy et al. (2006), pup abundance is still declining

significantly. There is also additional evidence for the oscillation between high and low pup

production years, both in maximum live pup counts and total pup production estimates. Given

that the most accurate data of changes in pup production are derived from the last four

pupping seasons, rates of change detected between the two high and low pup production

years suggest the actual rates of decline in pup production are much greater than those

observed using maximum live pup counts (-3.3 to 4.5% vs. -0.8% per breeding season,

respectively). Although the time series for pup production estimates is too short to provide

confidence in these rates, they are close to the rate of decline estimated by McIntosh (2007),

based upon a demographic model developed for the population. This model incorporated all

the available data from tagged and micro-chipped seals in the Seal Bay population to provide

estimates of survival, recruitment, fecundity and longevity, and model outputs suggested a -

4.5% decline per breeding season. Given the large uncertainty in the degree to which

maximum live pup counts mirror real changes in total pup production, and the corroboration

between rates of decline estimated from changes in total pup production over the last four

breeding seasons and a demographic model development from vital rates determined for the

Seal Bay population (McIntosh 2007); the best assessment of the current status of the Seal

Bay population is that it is declining by 3.3 to 4.5% per breeding season. This rate of decline

would see the population more than halve within 24-32 years (16-21 breeding

seasons)(McIntosh 2007).

Pup production estimates at the Seal Slide 22

4 PUP PRODUCTION ESTIMATES AT THE SEAL SLIDE

Introduction

This chapter details results from the survey of the Australian sea lion colony at the Seal Slide

(Kangaroo Island), using an approach developed by Goldsworthy et al. (2007a), termed the

cumulative mark and count (CMC) method that was used for the 2005-06 season. This

represents the second survey for the Seal Slide using this methodology.

Methods

The Australian sea lion colony known as the Seal Slide (-36°.028 S, 137°.539 E, Figure 2.1)

is located in the Cape Gantheaume Conservation Park, south-east Kangaroo Island. The

colony can be accessed by 4WD vehicle and was visited on five occasions during the 2007

breeding season (3 September, 18 September, 5 October, 22 October and 23 October).

The methodology to survey these sites followed that describe by Goldsworthy et al. (2007a)

for small colonies, termed the cumulative mark and count (CMC) method. During each visit,

attempts were made to mark a number of pups, by clipping a small patch of fur on the head

using scissors, and pups were also micro-chipped by implanting Passive Integrated

Transponder tags (PIT tags: TIRIS™ RFID 23mm, sterile single-use needle) subcutaneously

in the rump. As pups at Seal Bay (~24km away) were clip-marked on the rump, any

dispersing pups from either colony could be readily identified.

The number of marked, unmarked and dead pups sighted was recorded on each visit to the

colony, and where possible, additional pups marked. Marked pups at the Seal Slide were

also scanned for a microchip with a hand-held RFID PIT tag reader to confirm they were born

at the Seal Slide and not Seal Bay. Dead pups were covered with rocks to avoid repeat

counting on subsequent surveys. Pup numbers were estimated for each visit from the

numbers of marked pups and accumulated dead pups, plus the number of live unmarked

pups. The last item was estimated in several ways, and the maximum number was used to

estimate number of pups born to date. For the first visit, it was simply the number of

unmarked live pups seen. For the latter surveys it was the maximum number of unmarked

pups seen in one of the previous surveys, less pups marked since then.


In addition, the Petersen estimate was used to provide a mean estimate, with confidence

limits, following methods detailed in Chapter 3. The lower bounds in confidence limits were

determined by the minimum estimate of pup abundance based upon the CMC method.

Results

A total of 8 pups were marked over the five visits to the colony. Details on the number of

unmarked, marked and dead pups sighted on each survey are presented in Table 4.1. The

minimum number of marked, dead and unmarked pups present in the population, based on

the re-sight and marking history is also presented. Based on these data, the minimum

number of pups estimated to have been born in the subpopulation was 15, based on two

consecutive surveys undertaken on the 22 and 23 October (Table 4.1). This estimate is

greater than the 11 maximum live plus cumulative dead pups sighted on two of the surveys

(Table 4.1).

Petersen estimate results for the second to fifth surveys are given in Table 4.2. The surveys

conducted on 22 and 23 October were used to calculate a mean estimate of 16 pups (with

95% CL 14-18), as these two estimates were on consecutive days and undertaken when all

pups had been born. The minimum estimate of pups based on the CMC method bounds the

lower limit of the estimate, providing an over estimate of pup production for the Seal Slide of

16 pups (range 15-18).

Discussion

This is the second season for which the cumulative mark and count (CMC) method has been

used to estimate pup production at the Seal Slide. In both seasons the method has

demonstrated that not all pups were present or visible during any of the surveys. In the 2005-

06 survey, based on the CMC estimate, between 10-40% of pups were not sighted on each

survey (Goldsworthy et al. 2007a). Similarly, during the 2007 breeding season about one-

third (33%, SD = 4.8) of pups estimated to have been born based on the CMC method, were

not sighted on each survey (2nd 33%, 3rd 38%, 4th 33% and 5th 27%, based on results

presented in Table 4.1).


Trends in abundance

Although records of pups born at the Seal Slide go back to 1975 (Dennis 2005), the quality of

some surveys relative to the timing of breeding is uncertain, and as such there is the potential

that many of the pups recorded in the past at the Seal Slide may represent dispersed pups

from Seal Bay. To this end, Shaughnessy et al. (in press) restricted counts of pups to those

observed within four months of the beginning of the breeding season at Seal Bay. Although

controlling for dispersed pups from Seal Bay, this adjustment is likely to result in an

underestimate of actual pup production as it will omit pups born during the last third of the

breeding season. Surveys undertaken in the 2002/03 and 2004 breeding season differ from

earlier ones in that they included monthly surveys where only pups <1 month age (and

therefore assumed to have been born at the Seal Slide) were counted on each survey by

experienced observers. The cumulative number of pups <1 month old observed on each

survey was used to estimate the number of pups born in that season. Estimates based on

this method from these two seasons (2002/03 9 pups, 2004 11 pups), including the two using

the CMC methods (2005/06 10 pups, range 10-11 based upon Peterson estimate; 2007 16

pups, range 15-18) provides four consecutive breeding seasons with estimates of pup

production with a high level of confidence (Shaughnessy et al. in press, Goldsworthy et al.

2007a, this report). Although there is a general trend for an increase in pup production over

these four seasons, the rate of increase is not significant (F1,3=7.894, P = 0.1068, Figure 4.1).

Until data from more breeding seasons become available, the Seal Slide population appears

to be stable.


Table 4.1 Details of pup surveys undertaken at the Australian sea lion colony at the Seal Slide (Kangaroo Island) between September and October 2007. The number of clear (unmarked), marked, dead and total pups seen on each survey is indicated, in additional to the number of new marks applied. The number of marked pups available to be re-sighted at each survey is presented, along with the cumulative number of dead pups recorded. The maximum number of pups at each visit is estimated by summing the number of pups marked, maximum number of unmarked pups and cumulative dead pups.

Date Clear Marked Dead Dead Total Total live & New Cum. Min Cum. Min

count count clear marked live

count dead count marked marked Alive

dead clear Total

3-Sep 8 0 3 0 8 11 3 3 8 3 11

18-Sep 6 2 0 0 8 8 4 7 9 3 12 5-Oct 3 5 0 0 8 8 0 7 10 3 13

22-Oct 5 5 0 0 10 10 1 8 12 3 15 23-Oct 4 7 0 0 11 11 0 8 12 3 15

Table 4.2 Details of Petersen mark-recapture procedures undertaken at the Seal Slide between September and October 2007. M = number of marked pups in the population, n = the total number of pups sampled and m = the number of marked pups in each recapture sample. N = the estimated pup population size, ‘Dead’ is the cumulative number of unmarked dead pups, SE = standard error and V = variance. %m = the percentage of marked pups in each sample. The SE, CV (coefficient of variance), and Nlo (lower 95%confidence limit) and Nup (upper 95%confidence limit) are estimated from the last two surveys (22-23 October 2007). The overall mean estimate (in bold) is for the two final surveys (22-23 October) undertaken when the breeding season had ended.

Date M n m N Dead N+dead SE V %m CV Nlo Nup

18-Sep 3 8 2 11.0 3 14.0 2.4 6.0 25% 05-Oct 7 8 5 11.0 3 14.0 1.3 1.7 63% 22-Oct 7 10 5 13.7 3 16.7 1.9 3.5 50% 23-Oct 8 11 7 12.5 3 15.5 0.9 0.8 64%

Mean 22-23 Oct 13.1 16.1 1.03 50% 6.4% 14.1 18.1 (95% CL) (11-15) (14-18)


Figure 4.1 Trends in the abundance of Australian sea lion pups born at The Seal Slide (Kangaroo Island) over four consecutive breeding seasons between 2002-03 and 2007. Upper (95%) and lower (absolute minimum) confidence limits are given for the 2005-06 and 2007 breeding seasons.

Maintenance of the micro-chipping program 27

5 MAINTENANCE OF MICRO-CHIPPING PROGRAM

Introduction

Micro-chipping of pups with implanted radio-frequency identification (RFID) tags was

introduced in 1991 by Terry Dennis (former DEH employee). 50-60 pups of both sexes were

chipped each breeding season up to 2001 (Table 5.1). Nick Gales micro-chipped adult and

juvenile animals in 1989. The numbers of pups micro-chipped increased during the 2002-03,

2004 and 2005-06 breeding seasons, as part of R. McIntosh’s PhD research project (Table

5.1). During these seasons, pups were not captured in Pup Cove or the EPA, but some were

captured on the fringes of the EPA. At the end of the 2005-06 pupping season, at least 947

pups had been micro-chipped at Seal Bay, as well as some older animals. Here we describe

the methods used to micro-chip sea lion pups and detail the number of pups micro-chipped

during the 2007 breeding season at Seal Bay.

Methods

Pups less than two months of age and attended by an adult female were not considered

suitable for capture. Pups were captured by hand, and weighed (kg) in a canvas bag with the

aid of a spring balance to the nearest 0.1 kg. They were sexed and the standard length (cm)

from nose to tail was measured to the nearest 0.5 cm. Pups were marked externally by

clipping the fur of the rump and also by implanting Passive Integrated Transponder tags (PIT

tags: TIRIS™ RFID 23mm, sterile single-use needle) subcutaneously. PIT tags (micro-chips)

were inserted in the clipped area, parallel to the spine and close to the tail to minimise

gravitation. To successfully identify a pup, a PIT tag reader was held at a distance of up to

10cm from the insertion site.

Results

A total of 203 pups born in the 2007 breeding season at Seal Bay were micro-chipped. The

first pups were captured and micro-chipped on 7 September 2007, the last pups were micro-

chipped on 12 May 2008. Based on a total pup production estimate of 260 for the 2007

breeding season, and a minimum of 51 pup deaths, an estimated 209 live pups were

available at the end of the breeding season to microchip. The number micro-chipped

represents 98.5% of the estimated available pups and the largest number and proportion of

pups micro-chipped in a single cohort.


Table 5.1 Numbers of sea lion pups micro-chipped with RFID tags at Seal Bay (1989-2007).

(1989-2006 data from McIntosh 2007).

Breeding season No. pups micro-

chipped

1989-90 15

1991 58

1992-93 62

1994 49

1995-96 50

1997 57

1998-99 58

2000 51

2001-02 53

2002-03 148

2004 202

2005-06 144

2007 203

Discussion

Data from Seal Bay and other Australian sea lion colonies indicate that a high level of

variability in pup production between breeding seasons may be typical in this species. As

such, changes in pup production across successive breeding seasons may not provide

accurate measures of population status. Changes in population vital rates, such as age-

specific and cohort survival and recruitment rates provide better measures of the longer-term

demographic vulnerability of populations, and provide a better means to forecast future

population trajectories.

The benefits of having an individually-marked, known-aged population at Seal Bay have been

embraced by DEH and previous researchers that have undertaken studies at Seal Bay. In

1991, the tagging of pups using implantable RFID or PIT tags commenced, in conjunction

with a regular re-sight (scanning) program. Between 1991 and 2001, 50-60 pups were micro-

chipped each breeding season. Since 2002-03, the number micro-chipped increased to

between 144 and 202 per season, and in this most recent season 203 pups were micro-

chipped (Table 5.1). In addition to regular hand-held scanning, a number of automated


recording stations comprising RFID flat-bed aerials have been placed in the sand along major

sea lion paths between the beach and dune areas (Figure 5.1). This has greatly increased

the number of re-sight records of tagged animals, and improvements to these passive

recording systems are proposed, pending funding commitments.

McIntosh (2007) has undertaken the most comprehensive demographic analyses of the

species, principally from re-sight records of marked animals at Seal Bay. Important

information relating to the maintenance of the Seal Bay sea lion population can be gained

from maintaining this demographic program. It provides a context for pup abundance data,

and provides a means to examine the role of environmental factors in regulating sea lion

survival and fecundity, and for developing population models, from which future changes in

population trajectories can be predicted. With large numbers of pups being tagged within

each cohort, and the increased re-sighting probability as a consequence of passive receivers

placed within the colony, high quality re-sight data can be obtained readily and cost-

effectively and form the basis for assessing population status and health, and for further

demographic analyses.

Figure 5.1 Map of Seal Bay breeding colony, Kangaroo Island, extended to Bay 5, EPA. Western Positions of the automated scanners (AS) and the antenna type are noted by the coloured diamonds.

Future of population monitoring and research program at Seal Bay 30

6 FUTURE OF POPULATION MONITORING AND RESEARCH PROGRAM AT SEAL BAY

In 2007 Goldsworthy et al. (2007 c) produced a report that provided detailed

recommendations for a population monitoring and research program to be implemented to

assist management of the Australian sea lion population at Seal Bay. The report included a

historical summary of research and monitoring of the sea lion population, an evaluation of the

current status of the population, a detailed appraisal of the ongoing monitoring and research

needs, what an ongoing population monitoring and research program should consist of and

cost, and potential funding sources to support such a program. They concluded that during

the last 30 years, the focus at Seal Bay has been on visitor management and commercial

operations, and there has been limited and variable funding and human resources allocated

to monitor the sea lion population. As a consequence, the effort and consistency in

monitoring methods has varied considerably. For example, data on pup abundance has been

collected for most breeding seasons since 1973-74 (see Dennis 2005, McIntosh et al. 2006,

Shaughnessy et al. 2006). However, analysis of these data by Shaughnessy et al. (2006)

identified significant limitations and much of the data could not be used meaningfully.

Most of the data collected have been on live pup counts, and it is now known that such

indices of abundance significantly underestimate pup production, by as much as 187%

(McIntosh et al. 2006). The lack of focus and commitment of resources to population

monitoring have resulted in limited ongoing methodological evaluation to ensure that the data

are providing adequate monitoring of the status and trends in abundance of the population.

Such evaluation has only been done recently by University and Government based

researchers. Given the vagaries in the data available to date, the best appraisal of indices of

pup abundance over the last 20 plus years is that the population has been in steady decline

(Shaughnessy et al. 2006, McIntosh 2007).

Goldsworthy et al. (2007c) concluded that that investment in population monitoring over the

last 30 years has been inadequate and ill-directed, and resulted in:

• inappropriate survey methods being developed and used,

• no ongoing evaluation and analysis of data or methodologies,

• no formal assessment process to evaluate and report on the status and trends in

abundance in the population,

• a failure to detect systemic population decline, and

• limited implementation of research findings into day-to-day management activities.


Since the 2002-03 breeding season, considerable efforts have been made to develop more

appropriate methods to monitor the Seal Bay population (McIntosh et al. 2006, McIntosh

2007, Shaughnessy et al. 2006, this report).

Goldsworthy et al. (2007c,b) noted that in order to meet the long-term management needs of

Seal Bay to ensure that the sea lion population remains viable and economically sustainable

as a tourism destination into the future, a population monitoring and research program needs

to be established to monitor changes in the status, health and trends of the population, and to

identify, measure and mitigate threats. Such a program would provide critical performance

measures to assess whether or not the population is being appropriately managed, and

provide an effective insurance policy for the regional tourism industry.

Goldsworthy et al. (2007c) determined that a population monitoring and research program

should include both long-term monitoring and targeted research. Long-term monitoring

should focus on the assessment of pup production and mortality each breeding season, and

the monitoring of age-specific and cohort specific fecundity and survival rates. Targeted

research should focus on specific management needs. The most critical of these would be

those that aim to identify the cause(s) of decline in the population, and those that more

broadly target the monitoring and mitigation of threatening processes. The suggested

program is summarised below.

Long-term monitoring

Population status and trends in abundance The number of pups born per breeding season that survive to weaning is the most critical and

perhaps readily measured reproductive performance parameter in sea lion populations. It

provides an instantaneous measure of the number and quality of offspring able to be

produced by a population, and integrate information of the size, age-structure and fecundity

of populations, and the environmental conditions during the gestation and lactation period.

However, pup production and weaning rates are not straightforward to measure. The

Australian sea lion breeding season is lengthy, lasting up to 9 months in duration, and to

adequately estimate number of births and deaths requires some level of ongoing survey

throughout the breeding season to ensure that appropriate estimates can be calculated. A

problem with past monitoring programs has been that surveys of pup abundance by direct

counting have only estimated part of the pup production, and retrospective analyses have

identified that counting significantly underestimates the number of pups present in the colony

(McIntosh et al. 2006, McIntosh 2007, Shaughnessy et al. 2006).


Mark-recapture methods using the Petersen estimates, in conjunction with cumulative counts

of new births and deaths in the remainder of the colony during twice-weekly surveys of the

colony (as detailed in this report), provide the best methods to estimate pup production in the

population. Efforts to micro-chip all remaining live pups also provides a means to determine

the minimum pup production and fix the lower confidence limit of the estimate, ultimately

improving the precision of pup production estimates.

Monitoring of pup production and mortality would involve:

• Twice-weekly surveys of new births (with their location) and deaths (number and

cause) during the breeding season.

• Hair-clip marking, micro-chipping (internal PIT, RFID tags), sexing and measuring

(mass & length) of pups.

• Regular re-sighting efforts to determine which individuals are alive.

• Regular mark-recapture surveys undertaken throughout the breeding season.

• Strong scientific management and coordination of surveys.

• Results reported upon and reviewed shortly after each breeding season.

Population demography – monitoring of vital rates Data from Seal Bay and other Australian sea lion colonies indicate that a high level of

variability in pup production between breeding seasons may be typical in this species. As

such, changes in the pup production across successive breeding seasons may not provide

accurate measures of population status over short time periods. Changes in population vital

rates, such as age-specific and cohort survival and recruitment are likely to provide better

measures of the longer-term demographic vulnerability of populations, and provide a better

means to forecast future population trajectories.

The principal aims of an on-going demographic program should be to determine breeding

season and cohort-specific survival rates; and determine breeding season and cohort-

specific fecundity rates (as outlined in Goldsworthy et al. 2007c).

The achievement of these goals would require:

• RFID tagging (micro-chipping) of all live pups of each cohort;

• ongoing passive re-sighting from a network of aerials and data-loggers;

• active re-sighting program (using a hand-held aerial), especially for females and

mother-pup pairs during each breeding season (to monitor fecundity and maternity);

• strong scientific leadership and management with results reported upon and reviewed

regularly.


Targeted projects To complement long-term monitoring programs, there will be a need for targeted research to

support ongoing population management. The most critical of these will be those that aim to

identify the cause(s) of decline in the population, and understand more about threatening

processes with a view to monitor and mitigate them. The management of key anthropogenic

factors, such as fisheries interactions of sea lions, is a priority. Natural causes of mortality,

particularly the role and significance of disease and parasites, are poorly understood.

Knowledge of basic biological and ecological aspects of the species is still poor. Given that

the reproductive biology of Australian sea lions is unique among pinnipeds, the factors that

are important in maintaining populations of other species may not be the same for Australian

sea lions, hence a better understanding of the selective processes and environmental factors

that have shaped their unusual reproductive biology are important. Ensuring the long-term

sustainability of the Seal Bay population will require management of their foraging habitat and

prey resources (which may involve spatial and temporal management of fishing effort).

Knowledge of the species’ foraging habitats and prey, especially sex and age differences,

and how diet and foraging locations vary with season and year is poor. There is also a need

to ensure that visitor disturbance and commercialisation are ecologically sustainable and

sensitive.

There is an important role that research can play in educating the public about the biology

and ecology of Australian sea lions, and more broadly about the management of threatened

marine species. Given that Seal Bay is Australia’s largest sea lion tourism site, that South

Australia has about 80% of the sea lion population, and that the Australian Government Sea

Lion Recovery Plan is due to be released in 2009, there is an opportunity for the public focus

of the recovery of this species to be at Seal Bay. This provides unique educational and

marketing opportunities.

In summary, targeted research could include:

• studies on foraging habitats and diet, including sex and age differences, and season

and year differences;

• studies on the role of disease and parasites;

• threatening processes: identification, monitoring and mitigation (eg. fisheries

interactions);

• reproductive ecology;

• visitor interaction issues.


Recommendations

This report has provided additional support for the observation of an ongoing decline in the

Seal Bay Australian sea lion population. The current rate of this decline is estimated to be

between 3.3-4.5% per breeding season. Although there is some corroboration in these

values based on estimates of pup production over the last four breeding seasons and from a

model of the Seal Bay population (McIntosh 2007), both the time-series of pup production

estimates and the demographic factors upon which the population model was developed are

limited. As such there is a high degree of uncertainty in the actual and current rates of

decline, and in the expected trajectory of the population into the near future. This provides

significant challenges for State and Commonwealth threatened species managers, managers

of the Seal Bay Conservation Park, and presents sustainability issues for the Kangaroo

Island regional tourism industry.

The aims of this project were to ensure that continuity in monitoring of the Seal Bay

population is maintained until the resources required to implement an ongoing research and

monitoring program can be secured. Based upon the results presented in this report, the

need for a secured, fully funded research and monitoring program is pressing. Several

scenarios of research and monitoring programs were proposed by Goldsworthy et al.

(2007c). All of these fall well outside the funding presently available to monitor the Seal Bay

sea lion population.

The next breeding season at Seal Bay is scheduled to commence in October 2008. At

present there are no plans or funding dedicated to support a survey of pup production and

maintain the micro-chipping program in this season or any following seasons.

We make the following recommendations:

• A population monitoring and research plan needs to be developed and implemented.

This would aim to ensure that the status and health of the population are adequately

monitored and facilitate identification of the cause(s) of population decline;

• A population monitoring and research program should include both a long-term

monitoring program (monitoring of pup production, pup mortality and vital

demographic rates) and targeted projects that address specific data gaps and

management needs;


• The population monitoring and research program will require strong scientific

leadership and management, and results and methodologies should be reported upon

regularly, and reviewed;

• The absence of ongoing funding to support a population monitoring and research

program remains a critical issue for the future management and sustainability of Seal

Bay. The current level of State funding, and funding through competitive grants have

all been proven to be inadequate. A monitoring and research levy on visitor fees and

tourism operator licence fees should be investigated (Goldsworthy et al. 2007c).

Acknowledgments 36

7 ACKNOWLEDGMENTS

The work was conducted under an animal ethics permit from SA Department for Environment

and Heritage and the PIRSA Animal Ethics Committee. We thank Kate Lloyd and Peter

Canty (SA Department for Environment and Heritage) for provision of SA DEH Permits. We

thank Bill Haddrill for providing both staff and financial support to this program, and to the

DEH staff at Seal Bay for support of this work. We thank the Wildlife Conservation Fund for

funding support. Dr Ib Svane and Jason Nichols (SARDI) provided constructive review of this

report.

References 37

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Appendix 41

9 APPENDIX

Appendix 1 Results from 54 pup surveys of the Seal Bay Australian sea lion population undertaken between 30 May and 300 December 2007. Observers include Clarence Kennedy (CK), Rebecca McIntosh ( RM), Rachael Gray (RG). BP = Brown Pup, MP = moulted pup, New = new live pup, Chip = micro-chipped pup, Dead = new dead pup.

Accumulated count Total for day of survey Survey Observers Cumulative Cumulative Total live New Chipped New

No. Date Dead Born Alive count BP MP Births Total Dead 1 CK 30-May 0 1 1 1 0 0 1 0 0 2 CK 6-Jun 0 2 2 1 1 0 1 0 0 3 CK 12-Jun 0 2 2 1 1 0 0 0 0 4 CK 15-Jun 1 3 2 2 2 0 1 0 1 5 CK 19-Jun 1 5 4 3 3 0 2 0 0 6 CK 21-Jun 2 6 4 3 3 0 1 0 1 7 CK 26-Jun 2 9 7 6 6 0 3 0 0 8 CK 29-Jun 2 12 10 10 10 0 3 0 0 9 CK 5-Jul 2 13 11 9 9 0 1 0 0

10 CK 11-Jul 5 24 19 19 19 0 11 0 3 11 CK 13-Jul 5 28 23 21 21 0 4 0 0 12 CK 18-Jul 8 32 24 18 18 0 4 0 3 13 CK 24-Jul 13 49 36 31 31 0 17 0 5 14 CK 26-Jul 13 58 45 35 35 0 9 0 0 15 CK 30-Jul 14 65 51 38 38 0 7 0 1 16 CK 3-Aug 15 77 62 45 45 0 12 0 1 17 CK 7-Aug 15 85 70 50 50 0 8 0 0 18 CK 10-Aug 15 92 77 52 52 0 7 0 0 19 CK 13-Aug 16 100 84 49 49 0 8 0 1 20 CK 17-Aug 17 109 92 52 52 0 9 0 1 21 CK 22-Aug 20 119 99 65 65 0 10 0 3 22 CK 28-Aug 22 131 109 62 62 0 12 0 2 23 CK 31-Aug 27 145 118 88 88 0 14 0 5 24 CK 4-Sep 27 152 125 85 85 0 7 0 0 25 CK 7-Sep 28 156 128 94 94 0 4 0 1 26 CK 11-Sep 31 173 142 95 95 0 17 4 3 27 CK 16-Sep 31 179 148 99 99 0 6 5 0 28 CK 20-Sep 35 195 160 107 107 0 16 9 4 29 CK 24-Sep 37 207 170 93 93 0 12 9 2 30 RM, RG 26-Sep 37 208 171 78 78 0 1 10 0 31 RM, RG 27-Sep 37 211 174 100 100 0 3 15 0 32 RM, CK 28-Sep 37 212 175 124 124 0 1 19 0 33 RM, RG 1-Oct 38 214 176 111 111 0 2 17 1 34 RM, RG 2-Oct 38 215 177 100 100 0 1 12 0 35 CK 3-Oct 39 218 179 97 97 0 3 19 1 36 CK 5-Oct 40 222 182 99 99 0 4 20 1 37 CK 8-Oct 42 224 182 99 99 0 2 17 2 38 CK 12-Oct 42 227 185 78 78 0 3 22 0 39 CK 15-Oct 42 227 185 93 93 0 0 19 0 40 RM 17-Oct 42 228 186 121 120 1 1 32 0 41 RM 18-Oct 42 228 186 130 129 1 0 36 0 42 RM 19-Oct 42 228 186 127 127 0 0 33 0 43 CK 22-Oct 44 231 187 85 85 0 3 23 2 44 CK 26-Oct 44 232 188 84 84 0 1 17 0 45 CK 29-Oct 44 234 190 94 94 0 2 28 0 46 RM, RG 30-Oct 44 234 190 100 100 0 0 28 0 47 CK 1-Nov 44 235 191 111 111 0 1 47 0 48 RM, RG 3-Nov 44 236 192 145 145 0 1 52 0 49 CK 8-Nov 44 236 192 88 88 0 0 31 0 50 CK 15-Nov 46 238 192 105 105 0 2 40 2 51 CK 22-Nov 46 240 194 92 91 1 2 32 0 52 CK 28-Nov 49 243 194 97 95 2 3 44 3 53 CK 21-Dec 50 244 194 78 77 1 1 54 1 54 CK 30-Dec 51 245 194 124 116 8 1 77 1

Appendix 42

Appendix 1. cont. Mark recapture estimates Road Reserve

Survey RRE RRC No. M n m N sd BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 1 1 17 18 1 19 2 1 20 1 1 21 1 3 1 22 1 5 23 2 24 5 25 9 2 26 9 81 4 163 46 5 27 9 84 5 141 33 1 3 28 18 88 9 168 33 7 3 29 24 71 9 179 39 9 4 30 27 62 10 159 33 8 3 31 27 83 15 146 21 12 3 32 34 112 19 197 26 2 1 19 9 33 36 98 17 203 30 11 6 34 38 84 12 254 51 13 1 35 42 82 19 177 25 11 6 36 45 85 20 187 26 9 4 37 47 85 17 228 37 7 2 38 47 77 22 162 20 6 4 39 47 84 19 203 30 4 3 40 47 104 32 152 12 6 2 41 47 115 36 149 10 4 1 42 47 110 33 156 12 1 43 47 78 23 157 19 1 1 44 47 72 17 194 31 45 57 85 28 171 18 46 68 92 28 220 26 1 5 47 80 99 47 168 11 2 1 48 92 127 52 224 15 1 6 4 49 96 85 31 260 29 50 101 99 40 248 23 51 101 83 32 259 29 1 52 124 93 44 260 22 53 176 77 54 250 15 54 176 123 77 280 14 SUM 0 SUM 3

Appendix 43

Appendix 1. cont. Road Reserve WPA

Survey RRW SHELF Shelf Beach No. BP MP New Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 5 6 7 1 1 8 1 9 1

10 1 11 1 1 12 2 1 13 1 1 3 2 14 4 1 15 5 2 16 1 1 5 17 3 1 5 18 1 4 1 19 2 4 20 2 5 21 3 7 1 22 2 5 23 4 9 1 24 2 8 2 25 6 7 26 2 7 1 1 1 27 6 7 1 1 1 28 2 8 2 1 1 29 3 6 1 1 1 30 1 7 1 31 1 6 2 32 3 5 1 4 33 2 9 1 1 34 5 6 35 3 5 2 2 36 3 7 1 2 3 1 37 3 4 1 3 38 2 1 5 1 2 39 2 1 2 1 3 40 3 11 2 41 3 11 2 42 1 9 1 43 7 2 6 1 3 44 1 2 5 2 45 6 1 5 3 46 1 9 47 3 1 6 4 4 1 48 4 3 13 3 49 4 4 2 50 5 1 9 3 51 4 1 4 1 9 2 52 1 1 8 4 53 2 6 4 54 4 3 6 4 SUM 3 SUM 18 SUM 0

Appendix 44

Appendix 1. cont. WPA

Survey GROTTO Grotto Beach Grotto WU No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 1 24 2 1 25 26 1 1 27 1 28 29 30 2 1 31 2 32 2 33 2 34 4 1 35 2 1 3 1 36 2 37 3 38 2 39 2 1 40 3 41 3 42 5 3 43 1 1 44 2 45 4 3 46 7 2 47 3 2 2 48 5 1 2 49 2 1 50 7 4 51 12 2 52 17 7 1 53 8 6 1 54 9 8 SUM 3 SUM 2 SUM 1

Appendix 45


Survey Arch Pup Rock Pup Rock WU No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 1 1 1 24 25 1 1 26 1 1 27 1 28 29 3 1 30 3 1 31 4 1 32 5 1 33 4 1 34 4 2 35 4 2 36 4 1 1 1 37 6 2 38 6 2 39 4 2 40 9 4 41 1 5 42 8 3 43 5 2 44 3 1 45 1 2 46 4 47 1 1 6 3 2 48 9 5 49 9 3 1 1 50 9 4 51 4 2 4 1 52 2 2 53 2 1 54 13 6 1 SUM 0 SUM 4 SUM 1

Appendix 46

Appendix 1. cont.

Survey Sandy Beach SABER Saber WU

No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 5 6 7 8 9

10 11 12 13 3 3 14 4 1 15 3 16 3 17 4 18 5 1 19 7 1 20 6 21 6 2 5 1 22 5 3 1 1 23 4 1 6 1 24 7 1 3 25 8 8 26 4 1 8 2 27 5 2 1 28 4 2 1 6 1 1 29 4 1 2 1 30 6 31 9 3 32 9 1 33 8 1 34 4 35 1 4 1 36 2 3 1 37 2 1 3 1 38 2 2 1 39 5 1 3 1 40 5 1 41 7 1 42 6 43 2 3 1 44 1 1 1 45 4 3 1 46 6 3 47 1 1 48 2 1 49 1 2 50 1 1 1 51 52 2 1 53 6 4 54 2 1 2 2 SUM 4 SUM 13 SUM 0

Appendix 47


Survey Pebble Beach Pebble Beach WU Danger Point


10 1 1 11 1 12 1 13 1 14 2 1 15 3 16 4 1 17 5 1 1 1 18 4 19 3 1 20 5 1 21 2 3 1 22 4 1 23 4 24 4 25 4 1 1 26 5 3 1 27 6 1 28 5 1 1 29 5 2 30 4 1 31 7 1 2 32 7 2 33 8 2 34 8 3 35 3 1 1 36 2 6 2 37 3 38 11 4 39 4 2 40 5 3 41 2 1 1 1 42 5 1 43 44 4 2 3 1 45 3 3 1 46 2 1 3 1 47 2 1 48 1 1 3 2 49 2 2 2 2 50 3 2 5 2 51 2 1 52 5 1 3 4 3 53 3 1 4 4 54 4 1 8 5 SUM 15 SUM 1 SUM 1

Appendix 48


Survey DPCove Danger Cove WU West Cove No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 1 19 20 1 1 21 2 1 22 3 1 23 3 1 24 2 25 3 26 3 27 2 28 2 29 2 30 31 7 1 32 5 1 33 6 1 34 7 1 35 2 1 36 37 1 2 1 1 38 2 39 2 40 3 41 1 42 43 2 1 3 1 44 3 2 45 1 46 47 9 7 5 3 48 11 1 3 1 49 8 2 2 2 50 9 3 51 6 1 3 1 52 4 4 53 1 1 54 2 1 2 SUM 0 SUM 0 SUM 6

Appendix 49

Appendix 1. cont.

Survey West Cove WU WE Dunes West No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 1 1 3 1 4 1 5 1 1 1 6 1 1 7 2 1 2 1 8 1 1 3 1 3 9 1 2 2

10 1 5 2 1 5 3 1 11 1 5 1 6 1 12 1 3 9 3 3 13 1 1 7 1 7 4 1 14 2 1 7 2 7 1 15 2 5 1 12 2 1 16 3 1 9 2 7 2 1 17 3 1 7 7 18 4 1 9 1 9 2 19 3 9 1 1 9 2 20 3 9 2 9 2 21 4 7 1 1 4 2 22 4 1 9 2 9 1 1 23 9 1 6 8 24 6 9 1 9 25 5 13 1 9 26 6 1 12 2 7 1 27 7 14 1 9 1 28 11 2 4 1 1 12 2 1 29 6 1 6 1 1 1 30 9 3 1 31 8 1 1 32 7 1 6 33 4 12 1 34 7 1 8 35 3 8 2 4 36 2 5 9 1 1 1 37 3 6 2 8 38 11 1 1 1 1 1 39 9 2 4 40 12 3 4 41 5 1 42 1 3 7 2 43 7 1 2 1 1 1 3 44 6 1 5 1 45 4 1 13 6 46 9 2 13 6 47 7 4 13 9 48 9 4 5 3 49 2 5 1 7 3 50 1 2 51 4 2 8 3 52 2 1 1 1 4 1 53 1 1 5 3 54 7 5 1 SUM 12 SUM 33 SUM 33

Appendix 50

Appendix 1. cont.

Survey MBW Dunes Centre MBC No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 1 1 1 5 6 7 8 9

10 11 12 13 1 14 1 1 15 1 16 17 1 18 19 20 21 1 22 1 1 23 1 24 3 1 25 2 26 1 3 27 5 28 5 29 5 2 30 1 1 4 31 3 2 2 32 8 1 6 33 1 5 2 6 3 34 8 3 2 35 8 3 36 1 1 4 37 1 4 2 1 38 1 6 39 4 7 2 1 1 40 3 3 3 1 16 8 41 9 4 16 3 1 42 5 2 17 5 4 1 43 4 1 6 2 2 44 4 1 4 1 12 3 45 12 5 1 46 2 1 1 1 47 7 4 48 3 2 7 4 1 6 49 3 2 5 2 4 1 50 16 8 1 1 1 5 1 51 4 4 2 52 4 2 5 2 53 11 1 9 1 1 4 4 54 8 2 6 15 3 12 SUM 0 SUM 4 SUM 1

Appendix 51

Appendix 1. cont. EPA

Survey ED EMB Bay 1

No. BP MP New Chip Dead BP MP New Chip Dead BP MP New Chip Dead 1 2 3 4 5 6 1 1 7 8 1 1 9 1

10 2 2 11 3 1 12 2 13 6 4 2 14 3 15 3 1 16 7 2 17 7 2 18 8 1 19 7 1 20 9 2 21 7 22 8 2 23 16 6 4 24 14 1 25 13 1 26 13 3 2 27 1 1 13 1 28 1 17 2 2 29 1 14 3 30 1 15 31 2 19 2 32 2 19 2 33 1 1 17 1 34 1 7 1 35 1 15 2 36 1 21 1 4 37 1 21 3 38 1 16 2 39 1 1 1 21 1 40 1 1 1 15 3 41 2 2 1 43 16 42 1 1 1 37 11 43 4 15 4 1 44 1 11 1 45 12 2 11 4 46 15 4 16 2 47 7 4 15 1 1 48 5 2 8 5 27 1 49 3 2 2 15 5 50 2 1 5 1 3 1 12 5 51 1 4 1 3 11 1 1 4 52 8 6 5 2 14 2 4 53 9 7 7 6 54 1 1 9 2 8 12 7 SUM 1 SUM 1 SUM 42

Appendix 52

Appendix 1. cont.

Survey Bay 2

Bay 3

Bay 4


10 11 12 13 1 1 1 14 15 16 17 18 19 1 1 20 21 3 1 22 2 23 1 24 2 25 2 26 2 27 1 28 3 1 29 3 30 31 32 3 33 1 34 35 3 36 3 37 6 38 7 39 5 40 3 1 1 41 3 1 42 2 43 6 1 1 44 4 1 45 2 46 3 47 3 1 48 4 2 49 2 50 7 1 51 2 52 6 1 53 6 3 54 12 6 SUM 5 SUM 0 SUM 0

Appendix 53

Appendix 1. cont. Pup Cove

Survey

No. BP MP New Chip Dead total PC

1 0 2 0 3 0 4 0 5 1 1 1 6 1 1 7 1 1 8 1 1 9 2 1 2

10 5 3 5 11 4 4 12 0 13 1 1 14 5 1 5 15 4 1 4 16 5 2 5 17 7 2 7 18 6 6 19 1 1 1 20 1 2 1 21 7 1 7 22 1 2 1 23 13 2 13 24 9 9 25 11 11 26 14 3 1 14 27 15 2 15 28 19 4 19 29 22 4 22 30 16 16 31 17 17 32 12 12 33 13 13 34 16 16 35 15 15 36 14 14 37 14 1 1 14 38 1 1 39 9 9 40 17 1 17 41 15 15 42 17 17 43 7 7 44 12 12 45 9 1 9 46 8 8 47 12 12 48 18 18 49 3 3 50 6 6 51 9 1 9 52 4 1 1 4 53 1 1 54 1 1 1 SUM 38

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