hornsdale wind farm · r2 the coefficient of determination – the proportion of the variance in...

Hornsdale Wind Farm

Vegetation and PBTL Offset Annual Monitoring 2019

Hornsdale Wind Farm Vegetation and PBTL Offset Annual Monitoring 2019 30 May 2019

Version 2

Prepared by EBS Ecology for NEOEN

Document Control

Revision No. Date issued Authors Reviewed by Date Reviewed Revision type

1 17/05/2019 EBS Ecology Dr Marina Louter 29/05/2019 Draft

2 30/05/2019 EBS Ecology Final

Distribution of Copies

Revision No. Date issued Media Issued to

1 29/05/2019 Electronic Clément Viaud, NEOEN

2 30/05/2019 Electronic Clément Viaud, NEOEN

EBS Ecology Project Number: E70808

COPYRIGHT: Use or copying of this document in whole or in part (including photographs) without the written

permission of EBS Ecology’s client and EBS Ecology constitutes an infringement of copyright.

LIMITATION: This report has been prepared on behalf of and for the exclusive use of EBS Ecology’s client, and is

subject to and issued in connection with the provisions of the agreement between EBS Ecology and its client. EBS

Ecology accepts no liability or responsibility whatsoever for or in respect of any use of or reliance upon this report by

any third party.

CITATION: EBS Ecology (2019) Hornsdale Wind Farm Vegetation and PBTL Offset Annual Monitoring 2019. Report

to NEOEN. EBS Ecology, Adelaide.

Cover photograph: Austrostipa scabra (Spear Grass) +/- Themeda triandra (Kangaroo Grass) +/- Aristida behriana

(Brush Wire-grass) Open Grassland within the Native Vegetation and PBTL offset area.

EBS Ecology

125 Hayward Avenue

Torrensville, South Australia 5031

t: 08 7127 5607

http://www.ebsecology.com.au

email: [email protected]

Hornsdale Wind Farm Vegetation and PBTL Offset Annual Monitoring 2019

ii

GLOSSARY AND ABBREVIATION OF TERMS

BOM Bureau of Meteorology

DSE Dry Sheep Equivalent – standard measure of feed demand which represents a

50 kg wether which consumes 1.0 kg dry matter per day. A pregnant or lactating

ewe has a greater energy requirement, and the amount varies according to the

advancing pregnancy and the size of the lamb once it is born and feeding.

EBS EBS Ecology

EPBC Act Environment Protection and Biodiversity Conservation Act 1999

GPS Global positioning system

ha Hectare/s

Hole Any hole or burrow suitable for a PBTL

HWF Hornsdale Wind Farm

HWF1 Hornsdale Wind Farm Stage 1



MW Mega Watt

NPW Act National Parks and Wildlife Act 1972

NRM Natural Resources Management

NV Act Native Vegetation Act 1991

The Project Hornsdale Wind Farm: A 315MW renewable electricity project consisting of 99

wind turbine generators

PBTL Pygmy Blue-tongue Lizard (Tiliqua adelaidensis)

p-value The level of marginal significance within a statistical hypothesis test representing

the probability of the occurrence of a given event. The p-value is used as an

alternative to rejection points to provide the smallest level of significance at which

the null hypothesis would be rejected.

R2 The coefficient of determination – the proportion of the variance in the dependent

variable that is predictable from the independent variable(s).

SEB Significant Environmental Benefit

SEB offset area Area of land set aside for conservation, to offset for native vegetation clearance

during construction of the Project.

x̄ Sample mean


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EXECUTIVE SUMMARY

Background

Hornsdale Wind Farm (HWF) is a 315MW renewable electricity project consisting of 99 wind turbine

generators (the Project) located north of Jamestown in the Mid-North region of South Australia. The Project

area extends about 15 km in a north-south direction, and about 8 km in an east-west direction, covering a

site area of 75 ha. The Project was constructed in three stages (Stage 1 – 3), also known as HWF1, HWF2

and HWF3. The Hornsdale Wind Farm project was granted approval 10 May 2013, subject to conditions

under sections 130 (1) and 133 of the Environment Protection and Biodiversity Conservation Act 1999

(EPBC Act) (see EPBC Act referral 2012/6573).

To meet the requirements under the Native Vegetation (NV) Act 1991 (SA) a Significant Environmental

Benefit (SEB) Offset was calculated to offset the clearance of native vegetation associated with the

construction of the Project (see Hornsdale Wind Farm Native Vegetation Clearance Report (EBS Ecology

2013)).

As part of the EPBC Act approval process an SEB offset was calculated to offset the potential impacts to

the EPBC Act listed Pygmy Blue-tongue Lizard, Tiliqua adelaidensis, as a Significant Environment Benefit

Offset under the NV Act. An ‘area for conservation’ of 75 hectares was secured, of which 3.1 hectares

related to Tiliqua adelaidensis offset.

The required SEB Offset was achieved by offsetting a parcel of land known to support a population of

Pygmy Blue-tongue Lizard (PBTL), located on private property within the HWF (the SEB offset area).

Annual vegetation and PBTL surveys within the SEB offset area are part of a long term annual monitoring

program, which is an EPBC Act approval condition (approval 3d) for the development of the HWF (see

Hornsdale Wind Farm Annual Compliance Report under the EPBC Act September 2018 (EBS Ecology

2018)).

This report provides the results of the 2019 monitoring surveys for vegetation and PBTL within the SEB

offset area for HWF1, HWF2 and HWF3.

Vegetation monitoring

The primary aim of the annual vegetation surveys is to ensure that the vegetation within the SEB Offset

area is managed in a suitable way to protect the population of PBTLs within the site. This is achieved by

surveying vegetation transects within established quadrats within the SEB offset area. The first year of

vegetation monitoring surveys was undertaken in 2018 (EBS 2018) and therefore 2019 is the second year

of the monitoring program.

As 2019 is only the second year of the monitoring program, it is not possible to undertake any detailed

comparative data analysis. However, initial comparisons between the baseline data and the second year

of data indicate that the native grass tussocks are less dense, smaller and a shorter height than in 2018.

These changes can clearly be seen in the photographs taken during each survey. The reduction of grass

foliage may be due to the dry weather in 2018, in combination with grazing pressure from sheep and

kangaroos.


iv

Both the diversity and cover of weeds have increased since 2018, indicating that weed control (and weed

monitoring) is likely to be required on an ongoing basis.

The changes in vegetation within the SEB offset area between 2018 and 2019 are not considered to be

significant at this stage. However, should 2019 / 2020 also be dry years, it may be appropriate to reduce

the amount of grazing, in order to allow the grassland to recover. Future monitoring will provide more

extensive data, which will allow adaptive management recommendations to be made, if required.

PBTL monitoring

The primary aim of the PBTL surveys is to assess for any changes or impacts to the PBTL population

within the SEB Offset area. This is achieved by surveying PBTLs within 11 quadrats within the SEB Offset

area. Spider holes are checked for the presence of lizards using a Video burrowscope. The key results of

the 2019 survey include:

A total of 2,223 holes across the eleven quadrats were checked for PBTL occupancy in 2019, of

which 197 holes (9.45%) contained one or more PBTLs;

A total of 210 PBTLs were recorded in 197 holes (193 adults, 15 sub-adults and two juveniles);

The density of holes was highly variable over the SEB offset area, ranging from low (72 holes in

Quadrat 10) to high (421 holes in Quadrat 3);

The mean number of holes per quadrat observed in 2019 (x̄ = 239.63) was greater than the

baseline (x̄ = 126.38) and 2018 (x̄ = 132.00) surveys;

A total of 121 spiders were observed (x̄ = 13 individuals per quadrat);

A significant positive correlation between the number of holes and PBTLs present within a quadrat

was detected across the three survey years (p-value = 1.56e-05) (R2 = 0. 56); and

A significant positive correlation was also detected between the number of spiders and PBTLs

present within a quadrat across the three survey years (p-value = 0.021) (R2 = 0. 32).

Recommendations

To improve the annual monitoring program, it is recommended that:

Management continues to follow actions that are described in the SEB Management Plan (EBS

Ecology 2013 and 2017);

Quadrats should continue to be monitored annually in February for PBTL presence, and surveyors

should be kept constant, where possible, to ensure a robust dataset is compiled. Results from the

PBTL monitoring program could then be used to make adaptive management decisions that will

sustain and/or improve the quality of PBTL habitat in the SEB offset area.

Additional data on spiders holes (e.g. hole depth) should be collected to provide insight into the

availability of suitable holes for PBTLs;

Vegetation condition and rainfall data should continue to be incorporated in to future analyses of

PBTL survey data to help explain any annual variability in results. Analyses will become more

robust as more data is collected throughout the monitoring program;


v

Paddock management logs should be completed by landowners each year to provide greater

insight in to how vegetation condition (e.g. weed abundance) and grazing pressure (e.g. number

of grazers and regime) within the SEB area influence vegetation condition and the PBTL

population; and

Weeds should continue to be monitored and controlled, to avoid their spread.

Responsibilities

Hornsdale Asset Co previously negotiated an agreement with the landholders to manage the SEB offset

area. Whilst it will be the responsibility of the landholders to implement the Management Plan, HWF will

still be responsible for ensuring the plan is implemented to a suitable standard. If the implementation of

the plan does not occur or is not the required standard, HWF, in consultation with the landholder, can

undertake corrective action to ensure the plan is implemented. This may involve providing further direction

to the landholder or utilising the resources of an external contractor to implement specific tasks.


vi

Table of Contents

1 INTRODUCTION ...................................................................................................... 1

1.1 Approvals ................................................................................................................................... 1

1.2 Objectives .................................................................................................................................. 2

2 BACKGROUND ....................................................................................................... 4

2.1 Previous surveys and reports .................................................................................................... 4

2.2 SEB offset area .......................................................................................................................... 4

2.3 Current Management and Land Ownership .............................................................................. 5

2.3.1 Responsibilities ............................................................................................................. 5

2.4 Rainfall ....................................................................................................................................... 6

2.4.1 Long term rainfall .......................................................................................................... 6

2.4.2 Annual rainfall ............................................................................................................... 6

3 METHODS ............................................................................................................... 7

3.1 Field survey dates ...................................................................................................................... 7

3.2 Monitoring quadrats ................................................................................................................... 7

3.3 Monitoring history ...................................................................................................................... 7

3.3.1 Vegetation monitoring (12 quadrats) ............................................................................ 7

3.3.2 PBTL monitoring (11 quadrats)..................................................................................... 7

3.4 Vegetation monitoring procedure .............................................................................................. 9

3.5 Pygmy Bluetongue monitoring procedure ............................................................................... 12

3.6 Statistical analyses .................................................................................................................. 12

3.6.1 Vegetation monitoring ................................................................................................. 12

3.6.2 PBTL monitoring ......................................................................................................... 12

3.7 Limitations ................................................................................................................................ 13

3.7.1 Vegetation monitoring ................................................................................................. 13

3.7.2 PBTL monitoring ......................................................................................................... 13

4 VEGETATION MONITORING RESULTS .............................................................. 14

4.1 2019 results ............................................................................................................................. 14

4.1.1 Weather ...................................................................................................................... 14

4.1.2 Vegetation associations per quadrat .......................................................................... 14

4.1.3 Flora species diversity 2019 ....................................................................................... 15

4.1.4 Weed cover ................................................................................................................. 19

4.1.5 Tussock measurements .............................................................................................. 19

4.1.6 Additional data ............................................................................................................ 19

4.2 Comparison 2018 and 2019 results ......................................................................................... 21

4.2.1 Flora species diversity ................................................................................................ 21

4.2.2 Tussock measurements and additional data .............................................................. 24

4.2.3 Weed cover ................................................................................................................. 25


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5 PBTL MONITORING RESULTS ............................................................................ 26

5.1 Weather conditions during survey ........................................................................................... 26

5.2 2019 results ............................................................................................................................. 26

5.2.1 Quadrat 1 .................................................................................................................... 29

5.2.2 Quadrat 2 .................................................................................................................... 30

5.2.3 Quadrat 3 .................................................................................................................... 31

5.2.4 Quadrat 4 .................................................................................................................... 32

5.2.5 Quadrat 5 .................................................................................................................... 33

5.2.6 Quadrat 6 .................................................................................................................... 34

5.2.7 Quadrat 7 .................................................................................................................... 35

5.2.8 Quadrat 8 .................................................................................................................... 36

5.2.9 Quadrat 9 .................................................................................................................... 37

5.2.10 Quadrat 10 .................................................................................................................. 38

5.2.11 Quadrat 11 .................................................................................................................. 39

5.3 Comparison with PBTL baseline and 2018 results .................................................................. 40

6 DISCUSSION ......................................................................................................... 42

6.1 Vegetation monitoring .............................................................................................................. 42

6.2 PBTL monitoring ...................................................................................................................... 43

7 RECOMMENDATIONS .......................................................................................... 45

8 REFERENCES ....................................................................................................... 46

9 APPENDICES ........................................................................................................ 48

Appendix 1. Overview table of the GPS locations of monitoring quadrat markers. .................... 48

Appendix 2 – Vegetation Monitoring Results .............................................................................. 49

List of Tables

Table 1. Summary of the relevant approvals associated with the Hornsdale Wind Farm............. 1

Table 2. Hornsdale Wind Farm SEB offset area details. ............................................................... 5

Table 3. Summary of annual rainfall (Yongala Station, 2016 to 2018).......................................... 6

Table 4. Summary of vegetation associations and vegetation condition notes in 2019 within

each 1 ha vegetation monitoring quadrat. .................................................................... 14

Table 5. Native and introduced flora species recorded in 2019. ................................................. 15

Table 6. Native species recorded in the 1 ha quadrat in 2019. ................................................... 16

Table 7. Exotic species recorded in the 1 ha quadrat in 2019. ................................................... 17

Table 8. Percentage cover of weeds in quadrats, 2019. ............................................................. 19

Table 9. Tussock measurements 2019. ...................................................................................... 19

Table 10. Summary of data collected from the 1 x 1 m quadrats (2019). ................................... 20

Table 11. Number of weed species observed in the SEB area 2018 and 2019. ........................ 21


viii

Table 12. Summary information of species diversity recorded in the SEB offset area in 2018 and

2019. ............................................................................................................................ 22

Table 13. Average distance to tussock and average tussock width and height in 2018 and

2019. ............................................................................................................................ 24

Table 14. Summary of data collected from the 1 x 1 m quadrats in 2018 and 2019. .................. 25

Table 15. Weed cover within 1 x 1 m and 1 ha quadrats in 2018 and 2019. .............................. 25

Table 16. Weather observations for the duration of the PBTL survey (Yongala Station: 019062)

(BOM 2019). Asterisks indicate where no data was available. No data was available

for 3:00 pm for all days. ................................................................................................ 26

Table 17. Summary of the results from the 2019 PBTL monitoring quadrats. ............................ 27

Table 18. Comparison in the number of holes, spiders and PBTLs for each quadrat between the

baseline, 2018 and 2019 surveys. ............................................................................... 40

Table 19. Total numbers of each age class of PBTLs recorded in the baseline, 2018 and 2019

surveys. ........................................................................................................................ 41

Table 20. Native Flora species recorded within each 1 ha quadrat in 2018 and 2019. .............. 49

Table 21. Exotic Flora species recorded within each 1 ha quadrat in 2018 and 2019. ............... 51

List of Figures

Figure 1. Location of the Hornsdale Wind Farm and the SEB offset area. ................................... 3

Figure 2. Monthly rainfall from 2016 until the February 2019 vegetation and PBTL surveys

(Yongala Station: 019062) (BOM 2019). Mean rainfall for each month represented by

the dotted line. ................................................................................................................ 6

Figure 3. Location of the monitoring quadrats within the SEB offset area. PBTLs are not

monitored in Quadrat 12. ............................................................................................... 8

Figure 4. An example of a 1 ha monitoring quadrat with the layout of (1) a vegetation monitoring

transect with monitoring pins and (2) the location of a 1 x 1 m vegetation survey

quadrat. ........................................................................................................................ 10

Figure 5. Set-up of a vegetation transect and 1 x 1 m quadrat within the 1 ha quadrat. ............ 11

Figure 6. Set-up of each 1 x 1 m quadrat. ................................................................................... 11

Figure 7. Plot showing the positive correlation between the numbers of holes and number of

PBTLs observed within each quadrat in 2019 (R2 = 0.66). .......................................... 28

Figure 8. Boxplot showing the distribution (minimum, maximum, median, 25th and 75th

percentiles, outliers) of the numbers of PBTLs observed in quadrats on eastern (E)

and western (W) orientated slopes in 2019. ................................................................ 28

Figure 9. Location of holes surveys and PBTL observed within Quadrat 1 during the 2019

survey. .......................................................................................................................... 29


survey. .......................................................................................................................... 30


survey. .......................................................................................................................... 31


survey. .......................................................................................................................... 32


ix


survey. .......................................................................................................................... 33


survey. .......................................................................................................................... 34


survey. .......................................................................................................................... 35


survey. .......................................................................................................................... 36


survey. .......................................................................................................................... 37


survey. .......................................................................................................................... 38


survey. .......................................................................................................................... 39

Figure 20. Plot showing the positive correlation between the numbers of holes and number of

PBTLs observed within each quadrat for all years (R2 = 0.56). ................................... 41

Figure 21. Plot showing the positive correlation between the numbers of spiders and number of

PBTLs observed within each quadrat for all years (R2 = 0.32). ................................... 41


1

1 INTRODUCTION

Hornsdale Wind Farm (HWF) is a 315 MW renewable electricity project consisting of 99 wind turbine

generators located north of Jamestown in the Mid-North region of South Australia. The Project area

extends approximately 15 km in a north-south direction, and approximately 8 km in an east-west direction.

The Project was constructed in three stages, known as HWF1, HWF2 and HWF3, or Stage 1, 2 and 3.

A Significant Environmental Benefit (SEB) offset was required under the Native Vegetation Act 1991 (NV

Act) to offset the clearance of native vegetation associated the construction of HWF1, HWF2 and HWF3.

A Tiliqua adelaidensis (Pygmy Blue-tongue Lizard) (PBTL) offset was also required as part of an approval

condition under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), to

compensate for the impact to PBTL as a result of the wind farm development. The PBTL is listed as

nationally endangered under the EPBC Act and state endangered under the National Parks and Wildlife

Act 1972 (NPW Act).

The SEB offset for native vegetation has been delivered for all three stages of the project in a parcel of

land 142.54 ha in size, located immediately north of Hall Road (Figure 1). A significant population of PBTLs

is present within the SEB offset area. Therefore, the PBTL offset area of 3.1 ha has been incorporated into

the SEB offset area, which is protected under the NV Act and is listed on the property title.

The long term objectives of the monitoring program are to:

Conduct long-term (10 years) monitoring of native vegetation and the PBTL population to ensure

that suitable conditions are provided within the SEB offset area to maintain or increase existing

population numbers of PBTLs (including their habitat, refuges and habitat requirements and food

resources);

Identify any threats that may be occurring within SEB offset area; for example, weed incursions,

feral animals, or changes in vegetation structure, which may negatively affect the PBTL population;

and

Identify any actions that are required to maintain native grasslands with a rich diversity of species,

and little disturbance from exotic weeds.

1.1 Approvals

A summary of EPBC Act and previous NV Act approvals for the project are provided in Table 1.

Table 1. Summary of the relevant approvals associated with the Hornsdale Wind Farm.

Stage Relevant legislation Approval reference

HWF1 NV Act 2013/3012/764

HWF2 NV Act 2013/3012/764

HWF3 NV Act 2016/3101/764

All EPBC Act EPBC 2012/6573


2

1.2 Objectives

The objectives of this report are to:

Provide the results of the 2019 vegetation and PBTL annual monitoring surveys within the SEB

offset area;

Compare survey results between the current and previous surveys to identify if any obvious

changes in vegetation condition and/or the PBTL population are occurring within the SEB offset

area, and if so, examine how these factors influence one another; and

Provide recommendations to improve the management of vegetation within the SEB offset area to

improve vegetation condition and benefit the PBTL population.


3

Figure 1. Location of the Hornsdale Wind Farm and the SEB offset area.


4

2 BACKGROUND

2.1 Previous surveys and reports

Numerous flora and fauna assessments have been undertaken by EBS Ecology at HWF. An overview of

reports prepared between 2010 and 2018 is provided below for reference:

EBS Ecology (2018) Vegetation and PBTL Offset Monitoring – Hornsdale Annual Report 2018.

Report to NEOEN. EBS Ecology, Adelaide;

EBS Ecology (2018) Hornsdale Wind Farm SEB offset – Pygmy Blue-tongue Lizard Survey Annual

survey - 2018. Report to Asset Co. EBS Ecology, Adelaide;

EBS Ecology (2018) Hornsdale Wind Farm Stage 2 Native Vegetation Clearance Update August

2018. Report to NEOEN. EBS Ecology, Adelaide;

EBS Ecology (2018) Hornsdale Wind Farm Stage 3 Native Vegetation Clearance Update August


EBS Ecology (2017) Hornsdale Wind Farm Stage 1 Native Vegetation Clearance Update October


EBS Ecology (2017) Hornsdale Wind Farm SEB Offset Management Plan. Report to NEOEN. EBS

Ecology, Adelaide;

EBS Ecology (2017) Hornsdale Wind Farm Stage 3 Management Plan. Report to Hornsdale Wind

Farm Pty Ltd, EBS Ecology Adelaide;

EBS Ecology (2013) Hornsdale Wind Farm SEB –Native Vegetation and Pygmy Blue-tongue

Lizard Management Plan. Report to Investec Bank (Australia) Ltd. EBS Ecology, Adelaide;

EBS Ecology (2011) Hornsdale Flora and Fauna Assessment. Report to Aurecon. EBS Ecology,

Adelaide; and

EBS Ecology (2011) Mount Lock Flora and Fauna Assessment. Report to Aurecon. EBS Ecology,

Adelaide.

2.2 SEB offset area

The SEB offset area within the HWF was selected based on a number of key considerations:

The occurrence of a poor to moderate quality native grassland that could be improved over time

with active management;

The occurrence of a significant population (>30 individuals) of PBTLs; and

The location within the HWF Project area and the Northern and Yorke Natural Resources

Management (NRM) region.

Management plans have been prepared for the SEB offset area by EBS Ecology (EBS Ecology 2017), as

listed above. The management plan for the PBTL offset area devised long-term management measures

that will improve vegetation condition and protect PBTLs.


5

2.3 Current Management and Land Ownership

The SEB offset area has been owned by the Clark Brothers Shorts Trust since 2008 (Table 2). The land

was grazed heavily prior to its sale; however, the land was historically owned by a large pastoral company

which stocked it lightly. Since the land’s purchase in 2008, it has been lightly grazed by sheep, and mainly

by lambing ewes. Generally, little to no grazing occurs prior to May 1st each year, to facilitate the growth

of fodder. Pregnant or Lactating Ewes are typically stocked from the start of May to late August each year

at a rate of 2.5 ewes per hectare (n.b. not Dry Sheep Equivalent) (DSE) per hectare, which is standard for

stocking rate measure. Pregnant ewes can add 1.4 – 2.8 times DSE.

Uneven grazing pressure by sheep within the SEB area, due to the preferential grazing of eastern facing

slopes has resulted in ‘thatching’ of the native grass tussocks on the western slopes of the ridge (A. Brown

pers. comm. 2013). Many of the grass tussocks on the western slope accumulate high levels of dead

material at their centre, which impairs growth and causes radial dieback. Tussocks then become

fragmented and comparable to numerous small grasses in a circular formation, when in fact they are one

old, large tussock.

Table 2. Hornsdale Wind Farm SEB offset area details.

Owner Clark Brothers Shorts Trust

Manager Martin Clark

Address PO Box 233, Jamestown SA 5491

Local Government Area Northern Areas Council

NRM Region Northern and Yorke

Hundred Belalie

Parcel details F218216 A5, H240200 S298

Titles Vol 5727 Folio 243, Vol 5833 Folio 106

Location Hall Road, Jamestown

2.3.1 Responsibilities

Hornsdale Asset Co previously negotiated an agreement with the landholders to manage the SEB offset

area. Whilst it will be the responsibility of the landholders to implement the management plan, HWF will

still be responsible for ensuring the plan is implemented to a suitable standard. If the implementation of

the plan does not occur or is not the required standard, HWF, in consultation with the landholder, can

undertake corrective action to ensure the plan is implemented. This may involve providing further direction

to the landholder or utilising the resources of an external contractor to implement specific tasks.


6

2.4 Rainfall

Rainfall data is important as it impacts heavily on vegetation growth. As such, the monthly rainfall from

2016 to 2019 is provided below (Figure 2).

2.4.1 Long term rainfall

Monthly rainfall data was sourced from the closest weather station to HWF, which is located at Yongala

(Station: 019062). The recorded monthly rainfall at Yongala has been variable since the commencement

of the ecological monitoring program (Figure 2). Significant rainfall occurred in spring 2016 and summer

2016/17; however, the rainfall since has been relatively low (BOM 2019). As such, the annual rainfall in

2017 (300 mm) was substantially lower than 2016 (502 mm) (BOM 2019).

Figure 2. Monthly rainfall from 2016 until the February 2019 vegetation and PBTL surveys (Yongala Station:

019062) (BOM 2019). Mean rainfall for each month represented by the dotted line.

2.4.2 Annual rainfall

Table 3 (below) provides a summary of total annual rainfall and mean monthly rainfall from 2016 to 2018.

Table 3. Summary of annual rainfall (Yongala Station, 2016 to 2018).

Year Mean annual rainfall per month Total rainfall

2016 41.8 mm 502.4 mm

2017 25.04 mm 300.5 mm

2018 17.41 209 mm

0

20

40

60

80

100

120

J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D J

2016 2017 2018 19

Ra

infa

ll (m

m)

Month and Year


7

3 METHODS

3.1 Field survey dates

The annual vegetation monitoring was conducted from 12 to 14 February 2019 and the annual PBTL

monitoring was conducted from 11 to 14 February and 20 to 22 February 2019. Ecologists from EBS

Ecology undertook the survey work.

3.2 Monitoring quadrats

Monitoring was conducted within twelve quadrats (Figure 3). Eight quadrats (Quadrat 1 to 8) were

established in 2015 and four (Quadrat 9 to 12) were established in 2018. Of the twelve quadrats, eleven

are located within open grassland, while one (Quadrat 12) is located within a small area of Allocasuarina

verticillata (Drooping Sheoak) Woodland. Drooping Sheoak Woodland is considered unsuitable habitat for

PBTLs and, therefore, Quadrat 12 is not monitored for PBTL presence and abundance.

Each quadrat is 100 x 100 m (1 ha) in size and oriented in a north-south direction. A steel dropper is located

in each corner of the quadrat to permanently mark the sites. The GPS Coordinates of the corner posts for

each quadrat are provided in Appendix 1.

A photo of each quadrat is taken from the north-eastern corner looking to the south-western corner during

each annual monitoring survey. These photos are provided in Attachment 1.

3.3 Monitoring history

3.3.1 Vegetation monitoring (12 quadrats)

The baseline vegetation monitoring was undertaken in 2018 and, therefore, 2019 is the first year in which

any data analysis can be undertaken.

3.3.2 PBTL monitoring (11 quadrats)

Eight PBTL monitoring quadrats in HWF Stages 1 and 2 were established in 2015 and were

subsequently surveyed during the baseline survey (EBS Ecology 2016b). Quadrats 9 to 11 were set-up

and monitored, along with Quadrats 1 to 8, in 2018. Quadrats 1 to 11 were surveyed in 2019.


8

Figure 3. Location of the monitoring quadrats within the SEB offset area. PBTLs are not monitored in

Quadrat 12.


9

3.4 Vegetation monitoring procedure

The condition of vegetation within the SEB offset area was measured by laying out a 100 m tape measure

at each of the twelve I ha quadrats aligned approximately north-south, to form a transect (Figure 4).

The northernmost end of the tape was placed at the half way point between the north east post and north-

west post of the quadrat. A total of eight pins were positioned in the ground along the tape every ten

metres, starting at the 10 m mark and ending at the 80 m mark (Figure 5).

A 1 x 1 m vegetation survey quadrat was positioned at each of these locations, with the pin positioned at

the central point of each quadrat (Figure 6). This 1 x 1 quadrat is a standard size and the most frequently

used method for undertaking detailed vegetation assessments.

Each 1 x 1 m vegetation survey quadrat was further divided into four quarters (A – D), within which the

distance from the pin to the nearest tussock grass (in mm) was recorded. In addition, the basal width (in

mm) and vegetative height (in mm) (i.e. not including the flowering head) of each tussock were recorded.

In 2019, the following information was collected at each of the twelve quadrats:

The number of tussocks;

The number of juvenile tussock grasses (to establish the amount of regeneration at the site);

Percentage of dead material on the tussocks, averaged across the tussocks in the 1 x 1 m quadrat;

and

Percentage cover of weed species.

In addition, a brief walkover of the 1 ha quadrat was carried out, and the following recorded:

A list of all flora species present (native and exotic);

Approximate percentage cover of weed species;

A description of vegetation condition; and

Any notable changes since the previous year’s survey;

A photo was also taken at the north-east post of each 1 ha quadrat, facing south-west;


10

Figure 4. An example of a 1 ha monitoring quadrat with the layout of (1) a vegetation monitoring transect

with monitoring pins and (2) the location of a 1 x 1 m vegetation survey quadrat.


11

Figure 5. Set-up of a vegetation transect and 1 x 1 m quadrat within the 1 ha quadrat.

Figure 6. Set-up of each 1 x 1 m quadrat.


12

3.5 Pygmy Bluetongue monitoring procedure

Quadrats 1 – 11 were systematically traversed on foot by two surveyors at 4 m intervals. Each hole suitable

for PBTLs was marked with a GPS and an individual survey tag. All holes were subsequently examined

using an optic fibre ‘Videoscope’ (Yateks M Series) to determine whether holes were occupied. The

videoscope is an illuminated articulating insertion probe approximately 8mm in diameter, with a digital

video display screen. The probe can be easily directed into the spider burrow and bend around corners

with the use of a joystick. The optic fibre was slowly fed into each hole, until a lizard, spider or other fauna

was observed, or until the bottom of the burrow was reached. The survey method was consistent with the

Survey guidelines for Australia’s threatened reptiles: Guidelines for detecting reptiles listed as threatened

under the Environment Protection and Biodiversity Conservation Act 1999 (DSEWPC 2011). The presence

or absence of PBTLs, spiders and other fauna were recorded and for each hole occupied by PBTLs, the

number of individuals was recorded and their age (juvenile, sub-adult, adult) estimated. All survey tags

were removed at the completion of each survey.

Refer to the following reports for more detailed information on the Project, previous ecological

investigations and general information on PBTL ecology and behaviour.

EBS Ecology (2018) Hornsdale Wind Farm SEB offset – Pygmy Blue-tongue Lizard Survey Annual

survey - 2018. Report to Asset Co. EBS Ecology, Adelaide;

EBS Ecology (2018) Vegetation and PBTL Offset Monitoring – Hornsdale Annual Report 2018.

Report to NEOEN. EBS Ecology, Adelaide;

3.6 Statistical analyses

3.6.1 Vegetation monitoring

The vegetation monitoring program commenced in 2018 and therefore it is too early in the monitoring

program to undertake any meaningful data / statistical analysis. However, any observations of changes or

constants between 2018 and 2019 are reported in Section 4. Statistical analyses will be conducted in future

years to ascertain if any changes in the vegetation within the SEB offset area are occurring over the period

of the monitoring program.

3.6.2 PBTL monitoring

The PBTL data analysis was conducted using the R software environment for statistical and graphical

computing (R Core Team 2019).

Type II one-way ANOVAs were used for statistical analyses to detect differences in the number of

holes, spiders and PBTLs recorded in the baseline, 2018 and 2019 surveys.

Type II ANOVAs are used to test for effects in an unbalanced design when there is no interaction

observed between the explanatory variables, which is appropriate here given the different number

of quadrats sampled during the baseline survey and since no interactions between the explanatory

variables were detected.


13

Type II ANOVAs test for each main effect after the other main effect. A p-value of 0.05 was used

to infer a significant difference in PBTL numbers in response to the explanatory variables.

Type II two-way ANOVAs were used for statistical analyses to detect differences in the number of

PBTLs in response to year and the number of holes and spiders, respectively, as well as any

differences in the number of PBTLs, holes and spiders in response the various rainfall variables

(i.e. the total rainfall 12 months, three months, one month and three winter months preceding each

survey – data from BOM 2019).

A subset of the PBTL data (i.e. 2018 and 2019 data) was also analysed using ANOVA to test for

the influence of vegetation condition variables (collected during the 2018 and 2019 vegetation

surveys) on the number of holes, spiders and PBTLs.

3.7 Limitations

3.7.1 Vegetation monitoring

At the time of the 2019 survey, not all plants could be identified to species level due to lack of fruits or other

diagnostic features, caused by seasonal variation. However, this is not considered to be a significant

limitation to the vegetation survey as all plants were able to be identified at least to genus level.

3.7.2 PBTL monitoring

The ground cover of vegetation was at an optimal stage (reasonably dry and lacked growth) for conducting

searches for PBTLs, as the lack of vegetative growth aids in detecting holes. Despite the high search effort

(see Section 5.2) and favourable conditions of ground cover, some holes may have been missed due to

the inherent difficulty in detecting them (e.g. obscured by grass cover).

The PBTL demography data collected should be treated with caution, as it is difficult to distinguish age-

associated features with a Burrow-scope, particularly when views of lizard are restricted to within the hole

only.


14

4 VEGETATION MONITORING RESULTS

4.1 2019 results

The results of the 2019 vegetation monitoring surveys are presented below. A comparison of the data

recorded in 2018 and 2019 is provided in Section 4.2.

4.1.1 Weather

The total annual rainfall for 2018 was 209 mm (data from Yongala weather station). This is significantly

less than in 2017 (300.5 mm) and 2016 (502.4 mm). The effect of weather on vegetation monitoring results

is discussed further in Section 6.1

4.1.2 Vegetation associations per quadrat

A summary of each of the vegetation associations per quadrat is provided in Table 4 below.

Table 4. Summary of vegetation associations and vegetation condition notes in 2019 within each 1 ha

vegetation monitoring quadrat.

Quadrat Description

1

Dense tussocks of Themeda triandra (Kangaroo Grass) were present. The grassland had good

structural diversity with an abundance of dense tussocks. Few weeds were present. Young

Xanthorrhea sp. was regenerating.

2 Frequent weeds, particularly along the northern fence line where Salvia verbenaca var. (Wild Sage)

was abundant.

3

Open sward with lower-growing tussocks. Dominated by Aristida behriana (Brush Wire-grass) and

Austrostipa sp. (Spear-grass). The site is rocky and on a hill slope. Moderate to heavy grazing was

occurring by Kangaroos (Macropus sp.).

4

Less Avena barbata (Wild Oats) in this area, although this species was still frequent. Frequent

Rytidosperma caespitosum (Common Wallaby-grass) Aristida behriana and Austrostipa sp. tussocks

present, with occasional patches of Themeda triandra.

5

Low growing area (short sward) on the hill slope. There was frequent bare ground and very little litter

build up in this quadrat. Five Eastern Grey Kangaroos (Macropus gigantus) were seen during the

survey. Occasional patches of Wild Sage were present.

6 Dominated by Austrostipa sp. tussocks, with Aristida behriana and Rytidosperma caespitosum also

frequent. Wild Sage and Marrubium vulgare (Horehound) (Declared weed) were frequent.

7

The grassland was in good condition, with good structural diversity present (tall and low-growing

tussocks present with open areas between tussocks, grazed by kangaroos). Few weeds were present.

Moderately grazed by kangaroos. Cover of exotic species was approximately 15%. Dead Dog Rose

was noted.

8 Native grass species Austrostipa sp., Rytidosperma caespitosum and Aristida behriana tussocks were

frequent. Weeds/exotic species (particularly Avena barbata) were also frequent throughout.

9

Quadrat 9 was a very weedy site, dominated by Avena barbata and comprised approximately 70%

cover of exotic species. The site is located on the top of a steep slope. Wild Sage was frequent and a

few individual Horehound (Declared weed) plants were recorded. A few small patches of native

grasses were present.

10

Quadrat 10 is located in an area of poor-quality grassland dominated by Avena barbata, with frequent

weeds including Cucumis myriocarpus (Paddy Melon), Heliotropium europaeum (Potato Weed) and

Xanthium spinosum (Bathurst Burr). There was no bare ground present due to weeds and a layer of

dead annual weed grasses (Wild-Oats).

11

The grassland in this area is in good condition with few perennial weeds present. The area was

dominated by tussock grasses (with frequent Avena barbata) and provides good habitat for PBTL.

Kangaroo (Macropus sp.) scats were frequent in the quadrat.


15

Q12

This quadrat is located in a patch of Allocasuarina verticillata (Sheoak) woodland on a west-facing

slope. A moderate to high level of grazing (by Kangaroos) was occurring. The understorey was

dominated by Cryptandra amara (Bitter Cryptandra) and native tussock grasses. Very few weeds were

noted.

4.1.3 Flora species diversity 2019

Table 5 (below) provides a summary of native and exotic species recorded in 2019. A total of 40 species

were recorded which comprised 24 native species and 16 introduced weed species.

Table 5. Native and introduced flora species recorded in 2019.

Number of Weed Species 16

Number of Native Species 24

Total Species Diversity 40

A list of all native and exotic species recorded in 2019 is provided in Table 6 and Table 7 (below)

respectively.


16

Table 6. Native species recorded in the 1 ha quadrat in 2019.

Scientific name Common

name Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12

# of

Quadrats

Allocasuarina verticillata

Drooping Sheoak

3

Aristida behriana Brush Wire-grass

12

Austrostipa scabra group

Falcate-awn Spear-grass

12

Bursaria spinosa Bursaria 1

Calocephalus citreus Lemon Beauty-heads

3

*Cheilanthes sp. Cloak fern / Rock fern

2*

Convolvulus sp. Bindweed 4

Cryptandra amara Bitter Cryptandra

3

Enneapogon nigricans

Black-head Grass

3

Euphorbia drummondii

Spurge 5

*Glycine rubiginosa Twining glycine

2*

Lomandra sp. Mat-rush 1

Maireana enchylaenoides

Wingless Fissure-plant

4

*Rumex sp. Dock 3*

Rytidosperma caespitosum

Common Wallaby-grass

9

*Salsola australis Buckbush 1*

Sida sp. Sida 1

Teucrium racemosum Grey Germander

1

Themeda triandra Kangaroo Grass

7

Triodia sp. Spinifex 3


17

Vittadinia blackii Narrow-leaf New Holland Daisy

2

Vittadinia gracilis Woolly New Holland Daisy

2

Walwhalleya proluta Rigid Panic 2

Xanthorrhoea sp. Yacca/Grass-tree

3

Total native species / quadrat 8 4 8 6 10 8 5 8 8 4 7 13 24

*Species not observed in 2018

**Species not observed in 2019

Table 7. Exotic species recorded in the 1 ha quadrat in 2019.

Scientific name Common name Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 # of

Quadrats

Avena barbata Bearded Oat 12

Carthamus lanatus Saffron Thistle 6

*Cichorium intybus Chicory 1*

Cucumis myriocarpus Paddy Melon 2

Echium plantagineum Salvation Jane 9

Heliotropium curassavicum

Smooth Heliotrope 5

Heliotropium europaeum

Common Heliotrope

2

*Lolium sp. Rye-grass 1*

**Malva sp. Mallow

Marrubium vulgare Horehound 7

*Moraea setifolia Thread Iris 5*

Rosa canina Dog Rose 2


18

Species not observed in 2018


Salvia verbenaca var. Wild Sage 10

Sonchus sp. Sow-thistle 3

**Xanthium spinosum Bathurst Burr

Trifolium sp. Narrow-leaf Clover 9

Total weed species / quadrat 7 8 6 6 7 7 6 6 6 6 5 4 14


19

4.1.4 Weed cover

Table 8 shows the average percentage cover of weeds in each 1 x 1 m quadrat and each 1 ha quadrat in

2019.

Table 8. Percentage cover of weeds in quadrats, 2019.

Quadrat Average % weed cover

(1 x 1 m quadrat) % Weed cover (1 ha quadrat)

1 10 30

2 41 30

3 5 5

4 19 25

5 21 25

6 53 40

7 31 25

8 86 70

9 89 70

10 97.5 85

11 18.75 20

12 0.875 1

4.1.5 Tussock measurements

Table 9 provides the results of the measurements taken at each 1 x 1 m quadrat (i.e. distance to tussock

from the centre of the quadrat, basal width and vegetative height of each tussock) in 2019.

Table 9. Tussock measurements 2019.

Quadrat Average distance to

nearest tussock (mm)

Average basal

width (mm)

Average height

of grass (mm)

1 222 67 94

2 225 70 35

3 212 62 55

4 245 61 35

5 316 54 57

6 911 49 43

7 301 132 159

8 449 82 70

9 386 63 50

10 998 66 58

11 242 88 78

12 483 98 91

4.1.6 Additional data

Table 10 presents a summary of the average number of tussocks, juveniles and percentage cover of dead

material in the 1 x 1m quadrats in 2019.


20

Table 10. Summary of data collected from the 1 x 1 m quadrats (2019).

Quadrat Average number

of tussocks Average number

of juveniles % Dead material

1 15 3 77

2 12 1 86

3 19 4 66

4 16 1 82

5 10 2 83

6 10 1 96

7 9 1 88

8 7 0.25 94

9 8 0.5 97

10 3 1 95

11 15 2 83

12 13 2 70


21

4.2 Comparison 2018 and 2019 results

4.2.1 Flora species diversity

Table 12 lists all of the flora species recorded in 2018 and 2019 and illustrates which species increased or

decreased in frequency (i.e. the number of quadrats in which they were recorded).

Diversity of native species increased slightly in 2019. All 12 quadrats either increased slightly in native

species diversity or remained the same as in 2018. Three additional native species were recorded; these

were Cheilanthes sp. (Rock Fern/Cloak Fern) in Quadrats 3 and 5, Salsola australis (Buckbush) in Quadrat

9 and Glycine rubiginosa (Twining glycine) in Quadrat 3. The species with the greatest frequency and

abundance were native grasses Aristida behriana (Brush Wire-grass) and Austrostipa spp. (Spear-grass),

as in 2018.

The most diverse quadrat in 2019 (as in 2018) was Quadrat 12, which contained 13 native species. This

quadrat was located in the area of Allocasuarina verticillata (Drooping She-oak) Woodland, which was the

most species-rich and least weedy area within the SEB offset area.

Diversity of weed species increased in all but one quadrat in 2019. Three additional weed species were

recorded across the site; these were Cichorium intybus (Chicory) in Quadrat 7, Lolium sp. (Rye-grass) in

Quadrat 2 and Moraea setifolia (Thread Iris) in Quadrats 1, 3, 5, 8 and 11. The average percentage cover

of weeds also increased from 39% in 2018 to 52% in 2019. Frequency of some weed species increased;

for example, Wild Sage was recorded in an additional five quadrats in which it was not recorded in 2018.

The introduced annual species Avena barbata (Wild Oats) was the most frequent weed and was present

in every quadrat.

Two weed species recorded in 2018 were not recorded in 2019; these were Malva sp. (Mallow species)

and Xanthium spinosum (Bathurst Burr); however an exhaustive search of each 1 ha quadrat was not

undertaken (i.e. these species may have been present, but not recorded).

Table 11. Number of weed species observed in the SEB area 2018 and 2019.

2018 2019

Number of Weed Species 13 16

Number of Native Species 20 24

Total Species Diversity 33 40


22

Table 12. Summary information of species diversity recorded in the SEB offset area in 2018 and 2019.

Origin Scientific name Common name

2018 2019 2018 2019 Increase (+) or Decrease (-) or

no change # of Q’s # of Q’s % of Q’s % of Q’s

Native Allocasuarina verticillata Drooping Sheoak 1 3 8 25 +

Native Aristida behriana Brush Wire-grass 12 12 100 100 No change

Native Austrostipa scabra group Falcate-awn Spear-grass 12 12 100 100 No change

Native Bursaria spinosa Bursaria 1 1 8 8 No change

Native Calocephalus citreus Lemon Beauty-heads 1 3 8 25 +

Native *Cheilanthes sp. Cloak fern / Rock fern * 2 0 17 +

Native Convolvulus sp. Bindweed 2 4 17 33 +

Native Cryptandra amara Bitter Cryptandra 1 3 8 25 +

Native Enneapogon nigricans Black-head Grass 4 3 33 25 -

Native Euphorbia drummondii Spurge 1 5 8 42 +

Native *Glycine rubiginosa Twining glycine * 2 0 17 +

Native Lomandra sp. Mat-rush 2 1 17 8 -

Native Maireana enchylaenoides Wingless Fissure-plant 6 4 50 33 -

Native *Rumex sp. Dock * 3 0 25 +

Native Rytidosperma caespitosum Common Wallaby-grass 3 9 25 75 +

Native *Salsola australis Buckbush * 1 0 8 +

Native Sida sp. Sida 2 1 17 8 -

Native Teucrium racemosum Grey Germander 2 1 17 8 -

Native Themeda triandra Kangaroo Grass 6 7 50 58 +

Native Triodia sp. Spinifex 3 3 25 25 No change

Native Vittadinia blackii Narrow-leaf New Holland Daisy 1 2 8 17 +

Native Vittadinia gracilis Woolly New Holland Daisy 5 2 42 17 -

Native Walwhalleya proluta Rigid Panic 1 2 8 17 +

Native Xanthorrhoea sp. Yacca/Grass-tree 3 3 25 25 No change

Weed Avena barbata Bearded Oat 12 12 100 100 No change

Weed Carthamus lanatus Saffron Thistle 3 6 25 50 +

Weed *Cichorium intybus Chicory * 1 0 8 +

Weed Cucumis myriocarpus Paddy Melon 1 2 8 17 +

Weed Echium plantagineum Salvation Jane 1 9 8 75 +

Weed Heliotropium curassavicum Smooth Heliotrope 2 5 17 42 +

Weed Heliotropium europaeum Common Heliotrope 3 2 25 17 -

Weed *Lolium sp. Rye-grass * 1 0 8 +

Weed **Malva sp. Mallow 1 ** 8 0 -

Weed Marrubium vulgare Horehound 6 7 50 58 +

Weed *Moraea setifolia Thread Iris * 5 0 42 +

Weed Rosa canina Dog Rose 3 2 25 17 -

Weed Salvia verbenaca var. Wild Sage 6 10 50 83 +

Weed Sonchus sp. Sow-thistle 1 3 8 25 +

Weed Trifolium sp. Narrow-leaf Clover 2 9 17 75 +


23

Weed **Xanthium spinosum Bathurst Burr 1 ** 8 0 - Total Species Diversity 33 40 Number of Native Species 20 24 Number of Weed Species 13 16




24

4.2.2 Tussock measurements and additional data

Table 13 (below) provides the results of the measurements taken at each 1 x 1 m quadrat (i.e. distance to

tussock from the centre of the quadrat, basal width and vegetative height of each tussock). The results of

the 2019 surveys show:

The distance between each tussock and the central point in the quadrat has increased in all but

three of the quadrats since 2018. The average distance increased from 297 mm to 415 mm in

2019;

The average basal width has decreased in all but one of the quadrats. The overall average width

has decreased from 95 mm in 2018 to 74 mm in 2019; and

The average grass height decreased in all twelve quadrats in 2019. The overall total grass height

decreased from 157 mm to 68 mm.

Table 10 presents data that were only recorded in four of the quadrats in 2018 and it is therefore not

possible to make comparisons between years for all twelve quadrats. However, the number of tussocks

recorded in the four quadrats sampled in 2018 remained the same in 2019. In addition, the number of

juvenile grasses increased slightly from 0.95 to 1.28 and the average amount of dead material decreased

slightly, from 92% to 86% in the same four quadrats.

Table 13. Average distance to tussock and average tussock width and height in 2018 and 2019.

Quadrat

Average distance to nearest tussock (mm)

Average basal width (mm)

Average height of grass (mm)

2018 2019 2018 2019 2018 2019

1 240 222 129 67 210 94

2 375 225 85 70 140 35

3 153 212 72 62 136 55

4 245 245 87 61 107 35

5 324 316 63 54 145 57

6 197 911 98 49 173 43

7 235 301 114 132 279 159

8 377 449 135 82 198 70

9 492 386 69 63 100 50

10 474 998 91 66 95 58

11 216 242 119 88 136 78

12 236 483 88 98 166 91


25

Table 14. Summary of data collected from the 1 x 1 m quadrats in 2018 and 2019.

Quadrat

Average number of tussocks

Average number of juveniles

% Dead materials

2018 2019 2018 2019 2018 2019

1 - 15 - 3 - 77

2 - 12 - 1 - 86

3 - 19 - 4 - 66

4 - 16 - 1 - 82

5 - 10 - 2 - 83

6 - 10 - 1 - 96

7 - 9 1 88

8 - 7 - 0.25 - 94

9 8 8 0.10 0.5 97 97

10 6 3 1 1 96 95

11 12 15 0.12 2 97 83

12 12 13 3 2 79 70

4.2.3 Weed cover

Table 15 shows the average percentage cover of weeds in each 1 x 1 m quadrat and each 1 ha quadrat

in 2018 and 2019. As with Table 10, this data was only recorded in four of the quadrats in 2018 and

therefore only four of the quadrats can be compared. Comparisons between the four quadrats which were

sampled in both 2018 and 2019 show an increase in weeds from 39% to 52% in each of the 1 x 1 m

quadrats and a slight increase from 51 % to 58 % in the larger 1 ha quadrats.

Table 15. Weed cover within 1 x 1 m and 1 ha quadrats in 2018 and 2019.

Quadrat

Average % weed cover (1 x 1 m quadrat)

% Weed cover (1 ha quadrat)

2018 2019 2018 2019

1 - 10 - 30

2 - 41 - 30

3 - 5 - 5

4 - 19 - 25

5 - 21 - 25

6 - 53 - 40

7 31 25

8 - 86 - 70

9 62 89 70 70

10 88 97.5 80 85

11 7 18.75 <10 20

12 0.75 0.875 2 1


26

5 PBTL MONITORING RESULTS

5.1 Weather conditions during survey

The weather conditions during the field surveys were conducive to good detection rates of holes due to

the lack of movement in vegetation. Weather observations over the duration of the field survey from the

nearby Yongala weather station (approximately 20 km NE of the HWF) are shown in Table 16.

The ground cover vegetation was at an optimal stage (reasonably dry and lacked growth) for conducting

searches for PBTLs, as the lack of vegetative growth aided in detecting holes.

Table 16. Weather observations for the duration of the PBTL survey (Yongala Station: 019062) (BOM 2019).

Asterisks indicate where no data was available. No data was available for 3:00 pm for all days.

Date

Temp (°C) Rain (mm)

9:00 am

Min Max Temp (°C) Wind

direction Wind speed

(km/h)

11/02/2019 * 27.0 0 * * *

12/02/2019 11.0 20.9 0 16.5 W 15

13/02/2019 7.6 22.3 0 12.0 S 2

14/02/2019 8.0 27.1 0 13.9 SE 15

20/02/2019 8.5 27.1 0 13.8 SE 7

21/02/2019 11.5 29.0 0 14.5 SE 19

22/02/2019 12.3 30.5 0 16.9 SE 7

5.2 2019 results

A total of 2,223 holes across the eleven quadrats was checked for PBTL occupancy, of which 197 holes

(9.45%) contained one or more PBTLs (Table 17). Overall, 210 PBTLs were recorded in the 197 holes

(193 adults, 15 sub-adults and two juveniles). The lowest number of PBTLs was recorded in Quadrat 10

(2 individuals), which corresponds with the quadrat with the least holes (see below), and the highest

number of PBTL were recorded within Quadrat 6 (60 individuals from 313 holes checked), which also had

the greatest number of PBTLs in 2018 (56 individuals).

A total of 121 spiders were observed (x̄ = 13 individuals per quadrat), with the most in Quadrat 4 (29

individuals) and the least in Quadrat 8 (0 individuals) (Table 17).

The density of holes was highly variable over the SEB offset area, ranging from low (72 holes in

Quadrat 10) to high (421 holes in Quadrat 3). The density of holes within the SEB area did not appear to

be influenced by the aspect of the quadrat (i.e. 1148 holes on east versus 1075 on west facing slopes),

but rather geographical location, as the four quadrats (Quadrats 3, 4, 5 and 6) containing the most holes

were located next to each other (Figure 3 and Table 17).

As expected, a significant positive correlation was found between the number of holes and the number of

PBTLs present within a quadrat (p-value = 0.002; R2 = 0.66) (Figure 7): the greatest number of PBTLs

occurred at the quadrats with the most holes (Quadrats 3, 4, 5 and 6). There was no significant difference

in the number of PBTLs in response to aspect (p-value = 0.447) (Figure 8), or the interaction between the

number of holes and aspect (p-value = 0.156).The results for each monitoring quadrat are summarised in

Sections 5.2.1 to 5.2.11. Analysis with previous years’ data is presented in Section 5.3.


27

Table 17. Summary of the results from the 2019 PBTL monitoring quadrats.

Quad-rat

Aspect Holes with

PBTLs Juvenile

Sub-adult

Adult Total

PBTLs

% Holes with

PBTLs

Ants Centi-pede

Debris Empty hole

Scor-

pion Spider

Hole too

small Weevil

Total holes

1 W 11 4 9 13 6.21 5 0 112 0 0 9 7 33 177

2 E 20 1 21 22 10.15 12 0 113 2 1 18 6 25 197

3 W 29 34 34 6.89 7 0 276 0 1 4 24 80 421

4 E 35 1 1 33 35 10.32 8 1 224 0 0 29 5 37 339

5 W 12 2 12 14 5.29 8 3 148 0 0 0 10 46 227

6 E 58 7 53 60 18.53 15 0 177 0 0 25 6 32 313

7 W 4 1 3 4 3.96 4 0 62 0 0 11 5 15 101

8 E 10 10 10 7.04 7 0 107 0 0 8 0 10 142

9 E 9 9 9 10.59 1 0 45 0 0 7 3 20 85

10 E 2 2 2 2.78 17 1 31 2 0 3 4 12 72

11 W 7 7 7 4.70 3 0 86 0 0 7 8 38 149

Total 197 2 15 193 210 9.45 87 5 1381 4 2 121 78 348 2223


28

Figure 7. Plot showing the positive correlation between the numbers of holes and number of PBTLs observed

within each quadrat in 2019 (R2 = 0.66).

Figure 8. Boxplot showing the distribution (minimum, maximum, median, 25th and 75th percentiles, outliers)

of the numbers of PBTLs observed in quadrats on eastern (E) and western (W) orientated slopes in 2019.

100 200 300 400

01

02

03

04

05

06

0

Number of holes

Nu

mb

er

of P

TB

Ls

E W

01

02

03

04

05

06

0

Aspect

Nu

mb

er

of P

TB

Ls


29

5.2.1 Quadrat 1

A total of 177 holes was recorded within Quadrat 1 in 2019, 11 of which contained PBTLs (6.21%). A total

of 13 PBTLs were observed (nine adults; four sub-adults). Spiders and weevils were observed in nine and

33 holes, respectively (Table 17).

Figure 9. Location of holes surveys and PBTL observed within Quadrat 1 during the 2019 survey.


30

5.2.2 Quadrat 2


of 22 PBTLs were observed (21 adults; one juvenile). Spiders and weevils were observed in 18 and 25

holes, respectively (Table 17).



31

5.2.3 Quadrat 3

A total of 421 holes was recorded within Quadrat 3 in 2019, 34 of which contained PBTLs (6.89 %). A total

of 24 adult PBTLs were observed. Spiders and weevils were observed in four and 80 holes, respectively

(Table 17).



32

5.2.4 Quadrat 4


of 35 PBTLs were observed (33 adults; one sub-adult; one juvenile). Spiders and weevils were observed

in 29 and 37 holes, respectively (Table 17).



33

5.2.5 Quadrat 5

A total of 227 holes was recorded within Quadrat 5 in 2019, 12 of which contained PBTLs (5.29 %). A total

of 14 PBTLs were observed (12 adults; two sub-adults). No spiders were observed and weevils were

observed in 46 holes (Table 17).



34

5.2.6 Quadrat 6


of 60 PBTLs were observed (53 adults; seven sub-adults). Spiders and weevils were observed in 25 and

32 holes, respectively (Table 17).



35

5.2.7 Quadrat 7

A total of 101 holes was recorded within Quadrat 7 in 2019, four of which contained PBTLs (3.96%). A

total of four PBTLs were observed (three adults; one sub-adult). Spiders and weevils were observed in 11

and 15 holes, respectively (Table 17).



36

5.2.8 Quadrat 8


of 10 adult PBTLs were observed. Spiders and weevils were observed in eight and 10 holes, respectively

(Table 17).



37

5.2.9 Quadrat 9

A total of 85 holes was recorded within Quadrat 9 in 2019, nine of which contained PBTLs (10.59%). A

total of nine adult PBTLs were observed. Spiders and weevils were observed in seven and 20 holes,

respectively (Table 17).



38

5.2.10 Quadrat 10

A total of 72 holes was recorded within Quadrat 10 in 2019, two of which contained PBTLs (2.78%). A total

of two adult PBTLs were observed. Spiders and weevils were observed in three and 12 holes, respectively

(Table 17).



39

5.2.11 Quadrat 11

A total of 149 holes was recorded within Quadrat 11 in 2019, seven of which contained PBTLs (4.70%). A

total of seven adult PBTLs were observed. Spiders and weevils were observed in seven and 38 holes,

respectively (Table 17).



40

5.3 Comparison with PBTL baseline and 2018 results

The mean number of holes per quadrat observed in 2019 (x̄ = 239.63) was greater than the baseline

(x̄ = 126.38) and 2018 (x̄ = 132) surveys. However, there was no significant difference in the number of

holes between survey years (p-value = 0.169). The number of holes was greater than the previous two

surveys in all quadrats except in Quadrat 4, which had 110 more holes during the baseline survey, and

Quadrat 9, which had 85 holes in 2018 and 2019 (Table 18).

The mean number of PBTLs per quadrat observed in 2019 (x̄ = 24 individuals) was greater than the

baseline (x̄ = 17.38 individuals) and 2018 (x̄ = 21.25 individuals) surveys. However, there was no significant

difference in the mean number of PBTL between the 3 sampling years (p = 0.939). The proportion of adult

PBTLs observed in 2019 (91.9%) was greater in 2019 compared to the baseline (71.94%) and 2018

(83.53%) surveys. In contrast, the proportion of juveniles observed in the baseline survey (20.86%) was

greater than the 2018 (11.76%) and 2019 (0.95%) surveys. The proportion of sub-adults has remained

similar across all three surveys (7.19%, 4.71% and 7.14% in chronological order) (Table 19).

More spiders were recorded within each quadrat in the baseline survey (x̄ = 35.5 individuals) than the 2018

(x̄ = 7.9 individuals) and 2019 (x̄ = 13 individuals) surveys. This difference was statistically significant

(p-value = 0.035), with the Tukey post hoc test revealing a significant difference between the baseline and

2018 surveys (p-value = 0.038). The differences between the baseline and 2019, and 2018 and 2019

surveys were not significant (p-values = 0.079 and 0.926, respectively).

As expected, a significant positive correlation between the number of holes and PBTLs present within a

quadrat was detected across all surveys (p-value <0.001) (R2 = 0. 56) (Figure 20). A significant positive

correlation was also detected between the number of spiders and PBTLs present within a quadrat across

the three surveys (p-value = 0.021) (R2 = 0. 32) (Figure 21).

No correlations between the number of holes, spiders and PBTLs and the vegetation conditions variables,

collected in 2018 and 2019, and rainfall variables were detected (all p > 0.05).

Table 18. Comparison in the number of holes, spiders and PBTLs for each quadrat between the baseline,

2018 and 2019 surveys.

Quadrat No. of holes No. of spiders No. of PBTLs

Baseline 2018 2019 Baseline 2018 2019 Baseline 2018 2019

1 22 61 177 4 3 9 5 4 13

2 152 86 197 76 5 18 13 22 22

3 66 226 421 13 12 4 14 27 34

4 449 292 339 127 23 29 40 30 35

5 56 174 227 14 14 0 13 16 14

6 142 167 313 29 4 25 42 56 60

7 31 16 101 4 1 11 5 3 4

8 93 34 142 17 1 8 7 12 10

9 85 85 12 7 6 9

10 54 72 3 3 3 2

11 71 149 2 7 4 7

Mean 126.38 132.00 239.63 35.50 7.88 13.00 17.38 21.25 24.00

Total 1011 1266 2223 284 80 121 139 183 210


41

Table 19. Total numbers of each age class of PBTLs recorded in the baseline, 2018 and 2019 surveys.

Age class Baseline* 2018 2019

Adult 100 142 193

Sub-adult 10 8 15

Juvenile 29 20 2

Figure 20. Plot showing the positive correlation between the numbers of holes and number of PBTLs

observed within each quadrat for all years (R2 = 0.56).

Figure 21. Plot showing the positive correlation between the numbers of spiders and number of PBTLs

observed within each quadrat for all years (R2 = 0.32).

0 10 20 30 40 50 60

01

00

20

03

00

40

0

Number of PBTLs

Nu

mb

ers

of h

ole

s

0 10 20 30 40 50 60

02

04

06

08

01

20

Number of PBTLs

Nu

mb

ers

of sp

ide

rs


42

6 DISCUSSION

6.1 Vegetation monitoring

This report details the second year of the vegetation monitoring survey. As such, it is too early in the

monitoring program to undertake any detailed data analysis. Future monitoring will provide more

information on any changes in the sward composition and diversity, or any changes which may impact the

tussocky nature of the sward, which the PBTL rely on. Some initial comparisons based on data recorded

in 2018 and 2019 are discussed below.

The 2019 results show a slight increase in diversity of native species, with an additional three native

species recorded in 2019. This increase is not considered to be significant or to indicate a change in the

grassland per se. Tussocky native grass species Aristida behriana and Austrostipa sp. are still the most

abundant species on the site.

Quadrat 13, which is located in the area of Allocasuarina verticillata woodland, was the most species rich

and least weedy area of the site. Although it is relatively diverse in terms of native vegetation and in good

condition, it is not an area which is favoured by the PBTL, as they require a tussocky grassland habitat.

Nevertheless, it is an area of high ecological value and likely to provide habitat for native fauna such as

birds and invertebrates.

The 2019 results also show an increase in diversity of introduced weed species in almost all of the

quadrats, with an additional three weed species recorded. This could be a result of a number of factors;

e.g. weather conditions, or shorter grazing of the sward which may increase areas of bare ground between

the tussocks, thereby allowing new species to colonise. Sheep or vehicles may also bring in seed of seed

species from elsewhere on the property.

The frequency of some weeds on the site in 2019 also increased, indicating that some species may be

spreading on the site. For example, Wild Sage was recorded in five new quadrats in which it had not been

previously recorded. The average percentage cover of weeds also increased in 2019. These results are

not considered to be significant at this stage and may represent natural fluctuations. However, weed

monitoring and control is likely to be required at the site on an ongoing basis.

The results of the measurements of grass tussocks showed negative results and this can be seen in the

photographs provided in Attachment 1. The distance between each tussock and the central point in the

quadrat has increased in all but three of the quadrats since 2018 indicating that the cover (i.e. frequency

and density) of tussocks has reduced. The average basal width and height of the tussocks have also

decreased in all but one of the quadrats. These data therefore indicate that as well as the tussocks being

less dense, they are smaller in both width and height. This may be a result of the very low rainfall in the

months prior to the 2019 surveys, leading to reduced growth, in combination with grazing pressure. The

grasses do not appear to have been able to recover in the period in which they are not grazed. It may,

therefore, be appropriate to consider reducing the number of ewes grazing the area during dry years, or

after a number of consecutive dry years.

Additional data collected at all twelve quadrats in 2019 included recording the number of juvenile native

grasses, the number of tussocks in a quadrat and the amount of dead material in each of the eight 1m x


43

1m quadrats. These data were only collected for four of the 1 ha quadrats in 2018 and therefore it is not

possible to make comparisons between years for of the quadrats. However, the initial data indicate that

the number of tussocks in a 1m x 1m quadrat remained the same, the number of juvenile native grasses

increased slightly and the amount of dead material decreased slightly. The latter two changes are

considered negligible and are not considered to show any significant change in the grassland at this stage.

The photographs taken at the site (Attachment 1) show the changes in the grassland at eight of the

quadrats since 2015, and all twelve quadrats since 2018. The photos clearly show that the grass tussocks

are shorter and there appears to be more bare ground or litter between each tussock, as seen in the data.

6.2 PBTL monitoring

The mean number of PBTLs per quadrat observed in 2019 (x̄ = 24 individuals) was greater than the

baseline (x̄ = 17.38 individuals) and 2018 (x̄ = 21.25 individuals) surveys (Table 18), but there was no

significant difference between the number of individuals (p = 0.939), which indicated that the PBTL

population at Hornsdale has been stable over the past years. Further monitoring will determine the

trajectory or stochasticity of the PBTL population within the SEB offset area.

The slight increase in PBTL numbers from 2018 to 2019 could be in response to a reduction in ground-

cover vegetation due to below average rainfall in the year preceding each survey (Figure 2), but more data

will need to be collected to analyse such potential patterns. It is known that reduced ground-cover

vegetation facilitates an increase in foraging attempts and improves the visibility of predators while

individuals bask and forage (Pettigrew and Bull 2012). Increased foraging attempts can improve the body

condition of mature individuals, which can result in larger off-spring with better body condition (Milne et al.

2003). Juveniles in better body condition are expected to be more likely to be recruited into the adult

population, which may be particularly important for the conservation and growth of PBTL populations, as

it is estimated that less than 10% of juveniles survive to adulthood (Milne 1999).

Although PBTLs numbers were marginally greater in 2019 and 2018, the proportion of juvenile PBTLs

observed in the baseline survey (20.86%) was greater than the 2018 (11.76%) and 2019 (0.95%) surveys

(Table 19). Female PBTLs produce litters of 2-4 live young between late January and mid-March

(Hutchinson et al. 1994). As such, the difference in the number of offspring observed t is likely due to the

timing of the surveys, with the baseline survey undertaken in early to mid-May and subsequent surveys

undertaken in February.

The holes which PBTLs inhabit are constructed by lycosid and mygalomorph spiders, and as such, the

long-term conservation of PBTLs is reliant upon maintaining viable population of burrowing spiders

(Fellows et al. 2009). The number of spiders recorded within quadrats in the SEB offset area significantly

decreased between the baseline and 2018 survey (p-value = 0.038). However, spider numbers increased

between 2018 and 2019, and, although not significant (p-value = 0.926), the increase resulted in the

difference between baseline and 2019 spider numbers being insignificant (p-values = 0.079). Based on

the variability in the number of spiders observed thus far, further monitoring will determine the trajectory or

stochasticity of spider populations in the SEB offset area, which in turn may impact on the PBTL population.

The population dynamics of spiders, especially lycosids and mygalmorphs, are complex, with factors

including: prevailing weather, predation, parasitism and competition, all potentially impacting the number


44

of individuals present (Humphreys 1976; Conley 1984; Spiller and Schoener 1995). As such, the cause of

a potential reduction in spider number in the SEB offset area cannot be determined at present.

The total rainfall in the month preceding each survey and the number of spiders was positively correlated

(p-value = 0.015). However, this was likely due to two above-average outliers for the number of spiders

observed in the first survey year (76 and 127 spiders observed in Quadrats 2 and 4, respectively), which

skewed the data. This, combined with the month prior to the baseline survey receiving the highest rainfall

in comparison to the 2018 and 2019 surveys, explains why a correlation was detected. As more data is

collected, trends associated with rainfall data may become more apparent. No other correlations between

the number of holes, spiders and PBTLs and the vegetation conditions variables, collected in 2018 and

2019, and rainfall variables were found.

A significant positive correlation was detected between the number of spiders and PBTLs present within a

quadrat across the three surveys (p-value = 0.021) (R2 = 0. 32) (Figure 21). This is as unsurprising since

it is well-known that PBTLs occupy single-entrance, vertical burrows made by lycosid and mygalomorph

spiders (Hutchinson et al. 1994; Milne and Bull 2000; Milne et al. 2003; Souter et al. 2007).

Similarly, a significant positive correlation between the number of holes and PBTLs present within a

quadrat was detected across the three surveys (p-value < 0.001) (R2 = 0. 56) (Figure 20). This is as

expected since it is widely accepted that PBTLs occupy single-entrance, vertical burrows made by lycosid

and mygalomorph spiders (Hutchinson et al. 1994; Milne and Bull 2000; Milne et al. 2003; Souter et al.

2007).

The mean number of holes per quadrat observed in 2019 (x̄ = 239.63) was greater than the baseline

(x̄ = 126.38) and 2018 (x̄ = 132) surveys. However, this result was not significant (p-value = 0.169). The

number of holes was greater than the previous two surveys in all quadrats except Quadrat 4, which had

110 more holes during the baseline survey, and Quadrat 9, which had 85 holes in 2018 and 2019

(Table 18). Similar to the increase in PBTL numbers from 2018 to 2019, the increase in the number of

holes detected in 2019 could be due to a reduction in ground-cover vegetation due to below average rainfall

preceding each survey (Figure 2).

As in previous survey years, the number of holes varied considerably between individual quadrats in 2019.

Trends in the number of holes observed in eastern and western facing quadrats observed in previous years

(i.e. a reduction in the number of holes within eastern facing quadrats and an increase in the number of

holes within western facing quadrats between the baseline and 2018 survey), were not detected in the

2019 survey, with 1148 holes on east and 1075 on west facing slopes. The cause of the trend previously

observed is currently unknown; however, it may have been due to the grazing regime within the SEB offset

area (i.e. grazers favouring certain slopes). Future analysis that compares vegetation data between years

and in relation to PBTLs may provide an explanation for observed trends.


45

7 RECOMMENDATIONS

The following recommendations relating to both vegetation and PBTL monitoring and the overall

management of the SEB area are made:

Management continues to follow actions that are described in the SEB Management Plan (EBS

Ecology 2013 and 2017);

Quadrats should continue to be monitored annually in February for PBTL presence, and surveyors

should be kept constant, where possible, to ensure a robust dataset is compiled. Results from the

PBTL monitoring program could then be used to make management decisions that will improve

the quality of PBTL habitat in the SEB area;

Additional data on spiders holes (e.g. hole depth) should be collected to provide insight into the

availability of holes suitable for PBTLs;

Vegetation condition and rainfall data should continue to be incorporated in to future analyses of

PBTL survey data to help explain any annual variability in results. Analyses will become more

robust as more data is collected throughout the monitoring program;

Paddock management logs should be completed by landowners each year to provide greater

insight in to how vegetation condition (e.g. weed abundance) and grazing pressure within the SEB

offset area influence vegetation condition and the PBTL population;

Weeds should continue to be monitored and controlled, to avoid their spread; and

Should 2019 / 2020 also be a dry year, it may be appropriate to consider reducing the grazing

pressure at the site, to allow the grassland to recover.


46

8 REFERENCES

Bureau of Meteorology (BOM) (2019) Climate Data Online. Yongala (No. 019062). Available at:

http://www.bom.gov.au/climate/data/?ref=ftr [Accessed 12 April 2019].

Conley MR (1984) Predation versus resource limitation in survival of adult burrowing wolf spiders (Araneae:

Lycosidae). Oecologia 67, 71-75.

Department of Sustainability, Environment, Water, Population and Communities (DSEWPC) (2011)

Survey guidelines for Australia’s threatened reptiles: Guidelines for detecting reptiles listed as

threatened under the Environment Protection and Biodiversity Conservation Act 1999.

DSEWPC, Commonwealth of Australia. Available at:

https://www.environment.gov.au/system/files/resources/63db8a54-bfcb-429e-93b4-

e5efe21a356e/files/dsewpac-annual-report-12-13new.pdf [Accessed April 2019]

EBS Ecology (2011a) Mount Lock Flora and Fauna Assessment. Report to Client. EBS Ecology, Adelaide.

EBS Ecology (2011b) Hornsdale Flora and Fauna Assessment. Report to Aurecon. EBS Ecology,

Adelaide.

EBS Ecology (2012) Hornsdale Pygmy Blue-tongue Survey 2012. Report to IBAL on behalf of Aurecon.

EBS Ecology, Adelaide.

EBS Ecology (2015a) Hornsdale Wind Farm Pre-construction Pygmy Blue-tongue Lizard Management

Plan. Report to Neoen. EBS Ecology, Adelaide.

EBS Ecology (2015b) Hornsdale Wind Farm SEB – Native Vegetation and Pygmy Blue-tongue Lizard

Management Plan (28 May 2015 - Version 3.1). Report to Neoen. EBS Ecology, Adelaide.

EBS Ecology (2016a) Hornsdale Wind Farm – Annual Compliance Report under the EPBC Act. Report to

Neoen, EBS Ecology, Adelaide.

EBS Ecology (2016b) Pygmy Blue-tongue Lizard Scientific Monitoring and Research Plan - Progress

Report for 2015 and 2016. Report to Hornsdale Wind Farm Pty Ltd. EBS Ecology, Adelaide.

EBS Ecology (2017a) Hornsdale Wind Farm SEB offset Management Plan. Report to Hornsdale Wind

Farm Pty Ltd. EBS Ecology, Adelaide.

EBS Ecology (2017b) Hornsdale Wind Farm Stage 3 SEB offset Management Plan. Report to Hornsdale

Wind Farm Pty Ltd. EBS Ecology, Adelaide.

EBS Ecology (2018). Hornsdale Wind Farm Annual Compliance Report under the EPBC Act September

2018. EBS Ecology, Adelaide.

Fellows HL, Fenner AL, Bull CM (2009) Spiders provide important resources for an endangered lizard.

Journal of Zoology 279, 156-163.

http://www.bom.gov.au/climate/data/?ref=ftr

https://www.environment.gov.au/system/files/resources/63db8a54-bfcb-429e-93b4-e5efe21a356e/files/dsewpac-annual-report-12-13new.pdf

https://www.environment.gov.au/system/files/resources/63db8a54-bfcb-429e-93b4-e5efe21a356e/files/dsewpac-annual-report-12-13new.pdf


47

Humphreys WF (1976) The population dynamics of an Australian wolf spider, Geolycosa godeffroyi (L.

Koch 1865) (Araneae: Lycosidae). Journal of Animal Ecology 45, 59-80.

Milne T (1999) Conservation and the ecology of the endangered Pygmy Bluetongue Lizard Tiliqua

adelaidensis. PhD thesis. The Flinders University of South Australia.

Office of Environment and Heritage (OEH) (2009) Introducing photopoint and observational monitoring.

Office of Environment and Heritage, Government of New South Wales.

Milne T, Bull CM (2000) Burrow choice by individuals of different sizes in the endangered pygmy blue

tongue lizard Tiliqua adelaidensis. Biological Conservation 95, 295-301.

Milne T, Bull CM, Hutchinson MN (2003) Fitness of the Endangered Pygmy Blue Tongue Lizard Tiliqua

adelaidensis in artificial burrows. Journal or Herpetology 37, 762-765.

Pettigrew M, Bull M (2012) The response of pygmy bluetongue lizards to simulated grazing in the field

during three drought years. Wildlife Research 39, 540-545.

R Core Team (2019) R: A language and environment for statistical computing. R Foundation for Statistical

Computing, Vienna, Austria. Available at: https://www.R-project.org/.

Souter NJ, Bull CM, Lethbridge MR, Hutchinson MN (2007) Habitat requirements of the endangered pygmy

bluetongue lizard, Tiliqua adelaidensis. Biological Conservation 135, 33-45.

Spiller DA, Schoener TW (1995) Long-term variation in the effect of lizards on spider density is linked to

rainfall. Oecologia 103, 133-139.

https://www.r-project.org/


48

9 APPENDICES

Appendix 1. Overview table of the GPS locations of monitoring quadrat markers.

Monitoring quadrat

Survey marker

North-east South-east South-west North-west

Easting Northing Easting Northing Easting Northing Easting Northing

1 274553 6333589 274547 6333493 274447 6333504 274459 6333600

2 274885 6333546 274887 6333457 274782 6333443 274791 6333545

3 274587 6333218 274613 6333123 274511 6333122 274488 6333220

4 274923 6333245 274930 6333142 274819 6333120 274822 6333223

5 274623 6332969 274646 6332873 274548 6332850 274526 6332946

6 274971 6332890 274979 6332782 274877 6332867 274881 6332771

7 274601 6332627 274615 6332529 274513 6332525 274503 6332630

8 275060 6332684 275077 6332578 274981 6332562 274959 6332662

9 274896 6334207 274896 6334107 274796 6334107 274796 6334207

10 274866.6 6334408 274866.6 6334308 274766.6 6334308 274766.6 6334408

11 274422.6 6334716 274522.6 6334616 274422.6 6334616 274422.6 6334716

12 274613 6333981 274633 6333884 274540 6333866 274516 6333964

.


49

Appendix 2 – Vegetation Monitoring Results

Table 20. Native Flora species recorded within each 1 ha quadrat in 2018 and 2019.

Scientific name

Common name

Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 # of Quadrats

18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 2018 2019

Allocasuarina verticillata

Drooping Sheoak

1 3

Aristida behriana

Brush Wire-grass

12 12

Austrostipa scabra group

Falcate-awn Spear-grass

12 12

Bursaria spinosa

Bursaria 1 1

Calocephalus citreus

Lemon Beauty-heads

1 3

*Cheilanthes sp.

Cloak fern / Rock fern

2*

Convolvulus sp.

Bindweed 2 4

Cryptandra amara

Bitter Cryptandra

1 3

Enneapogon nigricans

Black-head Grass

4 3

Euphorbia drummondii

Spurge 1 5

*Glycine rubiginosa

Twining glycine 2*

Lomandra sp. Mat-rush 2 1

Maireana enchylaenoides

Wingless Fissure-plant

6 4

*Rumex sp. Dock 3*

Rytidosperma caespitosum

Common Wallaby-grass

3 9

*Salsola australis

Buckbush 1*

Sida sp. Sida 2 1

Teucrium racemosum

Grey Germander

2 1


50

Themeda triandra

Kangaroo Grass

6 7

Triodia sp. Spinifex 3 3

Vittadinia blackii

Narrow-leaf New Holland Daisy

1 2

Vittadinia gracilis

Woolly New Holland Daisy

5 2

Walwhalleya proluta

Rigid Panic 1 2

Xanthorrhoea sp.

Yacca/Grass-tree

3 3

Total native species / quadrat 6 8 4 4 5 8 4 6 8 10 6 8 4 5 4 8 5 8 3 4 8 7 12 13 20 24



51

Table 21. Exotic Flora species recorded within each 1 ha quadrat in 2018 and 2019.

Scientific name

Common name

Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Q11 Q12 # of Quadrats

18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 18 19 2018 2019

Avena barbata Bearded Oat 12 12

Carthamus lanatus

Saffron Thistle 3 6

*Cichorium intybus

Chicory 1*

Cucumis myriocarpus

Paddy Melon 1 2

Echium plantagineum

Salvation Jane 1 9

Heliotropium curassavicum

Smooth Heliotrope

2 5

Heliotropium europaeum

Common Heliotrope

3 2

*Lolium sp. Rye-grass 1*

**Malva sp. Mallow 1**

Marrubium vulgare

Horehound 6 7

*Moraea setifolia

Thread Iris 5*

Rosa canina Dog Rose 3 2

Salvia verbenaca var.

Wild Sage 6 10

Sonchus sp. Sow-thistle 1 3

**Xanthium spinosum

Bathurst Burr 1**

Trifolium sp. Narrow-leaf Clover

2 9

Total weed species / quadrat 2 7 4 8 3 6 1 6 3 7 3 7 4 6 5 6 7 6 4 6 5 5 1 4 13 14




EBS Ecology

125 Hayward Avenue

Torrensville, SA 5031

www.ebsecology.com.au

t. 08 7127 5607

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