Fisheries

Status of the Western Zone Greenlip Abalone (Haliotis laevigata) Fishery in 2014

B. Stobart, S. Mayfield and J. Dent

SARDI Publication No. F2014/000361-2 SARDI Research Report Series No. 865

SARDI Aquatics Sciences PO Box 120 Henley Beach SA 5022

September 2015

Report to PIRSA Fisheries and Aquaculture Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

Status of the Western Zone Greenlip Abalone (Haliotis laevigata) Fishery in 2014

Report to PIRSA Fisheries and Aquaculture

B. Stobart, S. Mayfield and J. Dent

SARDI Publication No. F2014/000361-2 SARDI Research Report Series No. 865

September 2015

II Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

This publication may be cited as: Stobart, B., Mayfield, S. and Dent J. (2015). Status of the Western Zone Greenlip Abalone (Haliotis laevigata) Fishery in 2014. Report to PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2014/000361-2. SARDI Research Report Series No. 865. 14pp.

Cover photograph: Juvenile greenlip abalone (Haliotis laevigata), B. Stobart. South Australian Research and Development Institute SARDI Aquatic Sciences 2 Hamra Avenue West Beach SA 5024

Telephone: (08) 8207 5400 Facsimile: (08) 8207 5406 http://www.pir.sa.gov.au/research

DISCLAIMER The authors warrant that they have taken all reasonable care in producing this report. The report has been through the SARDI internal review process, and has been formally approved for release by the Research Chief, Aquatic Sciences. Although all reasonable efforts have been made to ensure quality, SARDI does not warrant that the information in this report is free from errors or omissions. SARDI 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. The SARDI Report Series is an Administrative Report Series which has not been reviewed outside the department and is not considered peer-reviewed literature. Material presented in these Administrative Reports may later be published in formal peer-reviewed scientific literature.

© 2015 SARDI This work is copyright. Apart from any use as permitted under the Copyright Act 1968 (Cth), no part may be reproduced by any process, electronic or otherwise, without the specific written permission of the copyright owner. Neither may information be stored electronically in any form whatsoever without such permission.

Printed in Adelaide: September 2015

SARDI Publication No. F2014/000361-2 SARDI Research Report Series No. 865

Author(s): B. Stobart, S. Mayfield and J. Dent Reviewer(s): L. McLeay and C Noell Approved by: Dr Q. Ye Science Leader – Inland Waters & Catchment Ecology

Signed: Date: September 2015 Distribution: PIRSA Fisheries and Aquaculture, Western Zone Abalone Fishery licence holders, SAASC Library, University of Adelaide Library, Parliamentary Library, State Library and National Library Circulation: Public Domain

III Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

TABLE OF CONTENTS ACKNOWLEDGEMENTS ...... VI EXECUTIVE SUMMARY ...... 1 1. INTRODUCTION ...... 2 2. METHODS ...... 2 3. RESULTS ...... 3 Temporal patterns in catch, effort and CPUE ...... 3 Spatial assessment units: ...... 3 Risk of overfishing in SAUs and zonal stock status ...... 3 4. SUMMARY ...... 13 5. REFERENCES ...... 13

IV Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

LIST OF FIGURES

Figure 3.1. Catch, CPUE, PropG1 and TACC amendments of greenlip from the Western Zone from 1968 to 2014...... 5 Figure 3.2. Anxious Bay (high importance). Performance indicators catch, CPUE, PropG1, legal density, pre-recruit density, mortality and scores from the harvest strategy...... 6 Figure 3.3. The Gap (high importance). Performance indicators catch, CPUE, PropG1, legal density, pre-recruit density, mortality and scores from the harvest strategy...... 7 Figure 3.4. Avoid Bay (high importance). Performance indicators catch, CPUE, PropG1, legal density, pre-recruit density, mortality and scores from the harvest strategy...... 8 Figure 3.5. Flinders Island, Ward Island, Hotspot, Taylor Island and Point Avoid (medium importance). Performance indicators catch, CPUE, PropG1 and scores from the harvest strategy...... 10 Figure 3.6. South Nuyts Archipelago, Drummond, Reef Head, Baird Bay and Point Westall (medium importance). Performance indicators catch, CPUE, PropG1 and scores from the harvest strategy...... 10 Figure 3.7. Catch, CPUE and PropG1 of greenlip from low importance SAUs: Cape Bauer, Cape Catastrophe, Coffin Bay, D’Entrecasteaux Reef, Elliston Cliffs, Fishery Bay, Franklin Islands, Greenly Island, NE Thistle, Neptune Islands, North Nuyts Archipelago and Pearson Island from 1979 to 2014...... 11 Figure 3.8. Catch, CPUE and PropG1 of greenlip from low importance SAUs: Searcy Bay, Sheringa, Sir Joseph Banks, SW Thistle, Unassigned Region A, Unassigned Region B, Venus Bay, Waterloo Bay and Wedge Island from 1979 to 2014...... 12

LIST OF TABLES

Table 3.1. Outcome from application of the harvest strategy described in the Management Plan for the SAAF against the greenlip fishery in the Western Zone for 2014...... 4

V Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

ACKNOWLEDGEMENTS Funds for this research were provided by PIRSA Fisheries and Aquaculture, obtained through licence fees. SARDI Aquatic Sciences provided substantial in-kind support. We thank the Western Zone licence holders, fishers and shellers for providing length measurements of abalone in the commercial catch, and for their contribution to our understanding of the information presented in this report. We are grateful to Toby Fox, Dr Rowan Chick, Brian Foureur, Damian Matthews, Andrew Hogg, and other SARDI past and present divers for assistance with diving, and the collection and management of data. We thank Drs Paul Burch and Jonathan Carroll for statistical support and programming. This report was formally reviewed by Drs Lachlan McLeay and Craig Noell (SARDI Aquatic Sciences), Prof. Gavin Begg, Research Chief (SARDI Aquatic Sciences) and Dr Annabel Jones (PIRSA Fisheries and Aquaculture). It was formally approved for release by Dr Qifeng Ye, Science Leader – Inland Waters & Catchment Ecology, SARDI Aquatic Sciences.

VI Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

EXECUTIVE SUMMARY This report provides an assessment of the current stock status of Haliotis laevigata (greenlip abalone; hereafter termed greenlip) in the Western Zone (WZ) of the South Australian Abalone Fishery.

The assessment is required under the Management Plan for the South Australian Abalone Fishery which specifies the need for annual application of the harvest strategy to determine stock status and review the total allowable commercial catch. The harvest strategy is relatively new and several limitations have been identified. These include stock status classifications which are considered over-optimistic (e.g. Mayfield et al. 2014; Stobart et al. 2014) and the absence of a definition of recruitment overfished, to link the assessment to the National Fishery Status Reporting Framework (NFSRF; Flood et al. 2014). Consequently, the stock status outcome from the harvest strategy was compared to the traditional, weight-of-evidence analysis using the NFSRF framework.

The harvest strategy classified the zonal stock status for WZ greenlip in 2014 as ‘sustainably fished’. This was different from the classification of ‘under-fished’ in 2013.

The stock status classification from the harvest strategy – ‘sustainably fished’ – was not consistent with much of the data available for the fishery, because these data suggest greenlip stocks are at their weakest position in over 25 years; therefore, highlighting the limitations of the harvest strategy approach.

These data include: (1) a 14% reduction in zonal CPUE between 2012 and 2014, following a four-year period of stability, to a value among the lowest on record and lower than the mean CPUE in the 1980s; (2) declines in CPUE being spatially consistent across SAUs; (3) a reduced proportion of large greenlip in the catch from many SAUs despite market preference for large greenlip; (4) fishery-independent surveys at key sites showing low recruitment in recent years; (5) no evidence of stock recovery in several SAUs despite low recent catches; and (6) four of the six most important SAUs having a red risk of overfishing category (highest risk).

Collectively, this evidence demonstrates that current fishing pressure is too high and has the potential to cause the stocks to become recruitment overfished. However, there is more uncertainty in determining whether the stocks are recruitment overfished. Consequently, the WZ greenlip fishery is classified as ‘transitional depleting’ under the NFSRF. This was a change in the classification of these stocks from 2013 (‘sustainable’) and reflects the recent wide-spread deterioration in stock abundance.

1 Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

1. INTRODUCTION The Management Plan for the South Australian Abalone Fishery (PIRSA 2012) requires annual application of the harvest strategy to determine stock status and review the total allowable commercial catch (TACC). The most recent zonal stock status was provided in the stock assessment of greenlip abalone (Haliotis laevigata, hereafter referred to as greenlip), in the Western Zone Abalone Fishery (WZAF) by Stobart et al. (2014), when the stock status classification using the harvest strategy for the year ending 31 December 2013 was “under- fished”. That report was the first assessment of the combined WZ following the amalgamation of Regions A and B from 1 January 2014.

This status report forms part of the South Australian Research and Development Institute’s (SARDI – Aquatic Sciences) ongoing assessment program for this fishery. Future reports for greenlip are scheduled via a greenlip stock assessment in 2016 and a status report in 2017.

The stock status classification using the harvest strategy for the year ending 31 December 2014 was also compared to the traditional, weight-of-evidence analysis using the National Fishery Status Reporting Framework (NFSRF; Flood et al. 2012). This approach was taken because the harvest strategy for the South Australian Abalone Fishery (SAAF) has only recently been developed, several limitations have been identified and the harvest strategy is being reviewed in 2015/16.

2. METHODS Methods used to apply the harvest strategy and undertake the weight-of-evidence assessment are described in Stobart et al. (2012) and PIRSA (2012). Briefly, determination of the status of greenlip in the WZAF involves: (1) determination of the importance of spatial assessment units (single or multiple mapcodes intended to reflect abalone meta-populations; SAUs); (2) assigning each SAU to one of five risk-of-overfishing, color-coded, categories where the risk-of-overfishing category for each SAU is derived from the scoring of six performance indicators (PIs) in high importance SAUs or three PIs in medium importance SAUs, using prescribed reference points calculated from a 20-year reference period (1990- 2009); and (3) the resulting risk-of-overfishing color coded category for each SAU is linked to a score (range -2 to +2) and multiplied by the proportional contribution of that SAU to the combined catch, with the resulting values for all SAUs summed to determine the zonal stock status. The zonal status score also ranges between -2 and +2 and is allocated to one of five categories: 1) depleted (score ≤ -1.5); 2) overfished (-1.5 < score ≤ -0.5); 3) sustainably fished (-0.5 < score ≤ +0.5); 4) under fished (+ 0.5 ≤ score ≤ +1.5); and 5) lightly fished (score ≥ +1.5).

2 Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

3. RESULTS Temporal patterns in catch, effort and CPUE Western Zone Total catches were relatively stable from 1989 to 2009 (Figure 1). From 2009 to 2014, there has been a 13% reduction to the WZAF greenlip catch. This was due to the combined effects of a reduction in the Region A TACC from 2010, 33% and 25% decreases in TACC in Region B in 2011 and 2012, respectively, and the removal of one licence from the WZ in 2014. Catch per unit effort (CPUE) declined between 2003 and 2009, remained stable from 2009 to 2012 and declined further between 2012 and 2014. In 2014, CPUE was at the

lowest level since 1989 and 13% below the reference CPUE from 1990-2009 (CPUE90-09; the 20-year reference period from which the PIs are scored). Similarly, the proportion of Grade 1 greenlip in the commercial catch in 2014 was below the mean proportion from 1990-2009

(PropG190-09) and at the lowest level since 1996. Spatial assessment units The distribution of catch among SAUs changed between 2013 and 2014 (Figures 2-8), with considerable decreases from the Coffin Bay SAU and all Region B SAUs, particularly D’Entrecasteaux Reef. There were moderate increases in catch from Point Westall, Drummond, Baird Bay (Figure 6) and Flinders Island (Figure 5). The recent decline in zonal CPUE was reflected across most fishing grounds, including the three high-importance SAUs (Figures 2-8). With the exception of Baird Bay, Reef Head, South Nuyts Archipelago and

Point Westall, the CPUE in 2014 was substantially lower than CPUE90-09 and/or declining. Risk of overfishing in SAUs and zonal stock status In 2014, there were three high (Anxious Bay, The Gap and Avoid Bay) and ten medium- importance SAUs (Flinders Island, Ward Island, Hotspot, Taylor Island, Point Avoid, South Nuyts Archipelago, Drummond, Reef Head, Baird Bay and Point Westall; Table 1; Figures 2 - 6) for greenlip. Remaining SAUs were of low importance (Table 1; Figures 7 - 8). The risk-of-overfishing category could be determined for 12 (92%) of the 13 high and medium importance SAUs (Table 1). Limited data for estimating CPUE in one medium-importance SAU in 2014 (South Nuyts Archipelago) resulted in greenlip stocks in that SAU being categorised as uncertain (Table 1). The risk-of-overfishing for three high-importance SAUs was categorised green for Anxious Bay, red for The Gap and yellow for Avoid Bay (Table 1). Of ten medium importance SAUs, three were categorised red (Flinders Island, Ward Island, Hotspot), one green (Taylor Island), one dark blue (Point Westall) and four light blue (Point Avoid, Drummond, Reef Head, Baird Bay). The catch-weighted, zonal score was 0.04. Under the harvest strategy, this score defines the stock status of greenlip in the WZAF in 2014 as ‘sustainably fished’.

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Table 3.1. Outcome from application of the harvest strategy described in the Management Plan for the South Australian Abalone Fishery against the

Stobart greenlip fishery in the Western Zone for 2014. Grey shading identifies the performance indicators and their respective scores. ND indicates no data.

% contribution to % contribution to mean Catch-weighted al. et catch from high & Proportion Pre-recruit Legal Spatial assessment unit total catch (WZ) over the Importance CPUE PropG1 Mortality Combined PI score Risk of overfishing contribution to medium SAU in TACC Density Density last 10 years (05-14) zonal score 2014 Anxious Bay 5.1 High 14.95 -1 5 0 -3 -4 2 -1 0 0.00 The Gap 4.7 High 16.45 -2 1 -1 -5 0 0 -7 -2 -0.33 Avoid Bay 4.1 High 7.24 -2 0 0 0 -1 -2 -5 -1 -0.07 Flinders Island 2.8 Medium 6.74 -4 -8 0 - - - -12 -2 -0.13 Ward Island 2.4 Medium 5.61 -1 -1 -5 - - - -7 -2 -0.11 Hotspot 2.4 Medium 2.40 -2 -8 -2 - - - -12 -2 -0.05 Taylor Island 2.0 Medium 5.80 0 0 -2 - - - -2 0 0.00 Point Avoid 1.9 Medium 7.80 -1 8 0 - - - 7 2 0.16 South Nuyts Archipelago 1.8 Medium - ND -3 0 - - - Uncertain Not assigned - Drummond 1.7 Medium 11.88 -1 8 0 - - - 7 2 0.24 Reef Head 1.5 Medium 6.66 3 8 0 - - - 11 2 0.13 Baird Bay 1.5 Medium 6.67 6 1 4 - - - 11 2 0.13 Point Westall 1.4 Medium 7.81 0 2 4 - - - 6 1 0.08 Memory Cove 1.2 Low ------Not assessed Fishery Bay 1.1 Low ------Not assessed

4 North Nuyts Archipelago 1.0 Low ------Not assessed

Cape Catastrophe 1.0 Low ------Not assessed

SW Thistle 0.8 Low ------Not assessed 201

Venus Bay 0.7 Low ------Not assessed 5

Searcy Bay 0.7 Low ------Not assessed Western Zone Wedge Island 0.7 Low ------Not assessed Franklin Islands 0.6 Low ------Not assessed NE Thistle 0.5 Low ------Not assessed Coffin Bay 0.5 Low ------Not assessed

Green Cape Bauer 0.4 Low ------Not assessed DEntrecasteaux Reef 0.4 Low ------Not assessed Neptune Islands 0.4 Low ------Not assessed Harvestlip Strategy Report Unassigned WZ RG A 0.4 Low ------Not assessed Waterloo Bay 0.2 Low ------Not assessed Sheringa 0.2 Low ------Not assessed Elliston Cliffs 0.1 Low ------Not assessed Pearson Island 0.1 Low ------Not assessed Sir Joseph Banks 0.0 Low ------Not assessed Unassigned WZ RG B 0.0 Low ------Not assessed Greenly Island 0.0 Low ------Not assessed Sum 44.5 100.0 Zonal Stock Status 0.04

Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

Figure 3.1. Catch (t, meat weight; green bars) of greenlip from the Western Zone from 1968 to 2014. Mean CPUE ± se (kg.hr-1) and PropG1 are shown in red and blue lines, respectively. Red and blue dashed lines show the reference points CPUE90-09 and PropG190-09, respectively. Red arrows indicate implementation (1985) and amendment (1989, 2006 and 2010) of the TACC in Region A, blue arrows indicate implementation (1991) and amendment (1993, 1994, 2011 and 2012) of the TACC in Region B.

5 Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

Figure 3.2. Anxious Bay (high importance). Performance indicators catch (proportion of TACC), CPUE (kg.hr-1), PropG1, legal density (no.m-2), pre-recruit density (no.m-2), mortality (Z) and scores from the harvest strategy in brackets. Red and blue lines are upper and lower limit and target reference points, respectively. Green bars describe the data and time over which the reference points were calculated, open bars describe the measures of the PI outside the reference period and orange bars the data and year subject to assessment for each PI, i.e. the score-year.

6 Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

Figure 3.3. The Gap (high importance). Performance indicators catch (proportion of TACC), CPUE -1 -2 -2 (kg.hr ), PropG1, legal density (no.m ), pre-recruit density (no.m ), mortality (Z) and scores from the harvest strategy in brackets. Red and blue lines are upper and lower limit and target reference points, respectively. Green bars describe the data and time over which the reference points were calculated, open bars describe the measures of the PI outside the reference period and orange bars the data and year subject to assessment for each PI, i.e. the score-year.

7 Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

Figure 3.4. Avoid Bay (high importance). Performance indicators catch (proportion of TACC), CPUE (kg.hr-1), PropG1, legal density (no.m-2), pre-recruit density (no.m-2), mortality (Z) and scores from the harvest strategy in brackets. Red and blue lines are upper and lower limit and target reference points, respectively. Green bars describe the data and time over which the reference points were calculated, open bars describe the measures of the PI outside the reference period and orange bars the data and year subject to assessment for each PI, i.e. the score-year.

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Figure 3.6. South Nuyts Archipelago, Drummond, Reef Head, Baird Bay and Point Westall (medium importance). Performance indicators catch (proportion of TACC), CPUE (kg.hr-1), PropG1 and scores from the harvest strategy in brackets. Red and blue lines are upper and lower limit and target reference points, respectively. Green bars describe the data and time over which the reference points were calculated, open bars describe the measures of the PI outside the

reference period and orange bars the data and year subject to assessment for each PI, i.e. the score-year. ND indicates no data.

catch scales varyamong graphs. CPUE show lines dashed blue and red applicable, (kg.hr Bay, se ± CPUE Coffin 2014. to 1979 from Catastrophe, Island Pearson and Archipelago Cape Nuyts North Islands, Neptune Thistle, Fra Bauer, Bay, Fishery Cape Cliffs, Elliston SAUs Reef, D’Entrecasteaux importance low from greenlip Figure catch scales varyamong graphs. CPUE show lines dashed blue and red applicable, (kg.hr Bay, se ± CPUE Coffin Catastrophe, NE Island, and Archipelago Cape Greenly Nuyts North Islands, Islands, Neptune Thistle, Franklin Bauer, Bay, Fishery Cape Cliffs, Elliston SAUs Reef, D’Entrecasteaux importance low from greenlip Figure graphs. among vary (kg.hr r applicable, se ± CPUE 2014. to 1979 from Island Pearson and Archipelago Nuyts North Islands, Neptune Thistle, NE Island, Greenly Re D’Entrecasteaux Bay, Coffin Catastrophe, Cape Figure catch scale CPUE show lines dashed blue and red applicable, (kg.hr Bay, se ± CPUE Coffin Catastrophe, NE Island, Cape Greenly Islands, Neptune Thistle, Bauer, Franklin Bay, Cape Fishery Cliffs, SAUs Elliston Reef, importanceD’Entrecasteaux low from greenlip Figure Stobart

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Figure 3.7. Catch (t, meat weight; green bars) of greenlip from low importance SAUs Cape Bauer, Cape Catastrophe, Coffin Bay, D’Entrecasteaux Reef, Elliston Cliffs, Fishery Bay, Franklin Islands, Greenly Island, NE Thistle, Neptune Islands, North Nuyts Archipelago and Pearson Island from 1979 to 2014. -1 CPUE ± se (kg.hr ) and PropG1 are shown in red and blue lines, respectively. Where applicable, red and blue dashed lines show CPUE90-09 and PropG190-09, respectively. Note catch scales vary among graphs.

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Figure 3.8. Catch (t, meat weight; green bars) of greenlip from low importance SAUs Searcy Bay, Sheringa, Sir Joseph Banks, SW Thistle, Unassigned Region A, Unassigned Region B, Venus Bay, Waterloo Bay and Wedge Island from 1979 to 2014. CPUE ± se (kg.hr-1) and PropG1 are shown in red and blue lines, respectively. Where applicable, red and blue dashed lines show CPUE90-09 and PropG190-09, respectively. Note catch scales vary among graphs.

Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

4. SUMMARY The harvest strategy for the South Australian Abalone Fishery (PIRSA 2012) is the current tool for setting TACCs in this fishery and designed to monitor abalone stocks using biological PIs in SAUs of high and medium importance, assess the risk of overfishing in each SAU in relation to their overall fishery importance to determine a stock status for the zone and adjust TACCs in response to changing abalone populations. In 2014, application of the harvest strategy to determine stock status for greenlip in the WZ was based on 13 SAUs, providing a broad representation of fished stocks. However, this relatively new harvest strategy has several limitations including stock status classifications which are considered overoptimistic (e.g. Mayfield et al. 2014; Stobart et al. 2014) and the absence of a definition of recruitment overfished, to link the assessment to the NFSRF (Flood et al. 2014). The lack of an agreed definition makes determining whether stocks are recruitment overfished problematic. As the harvest strategy is being reviewed in 2015/16, the stock status classification from the harvest strategy for greenlip was compared to the traditional, weight-of-evidence analysis using the NFSRF framework. Identification of a definition of recruitment overfished for the fishery is a key component of that review, and a conservative approach is advised given the propensity for abalone stocks to decline rapidly, substantially and without recovery (Mayfield et al. 2012).

The zonal stock status score from the harvest strategy has changed to 0.04 from 0.56 (Stobart et al. 2014), denoting a change in status from “under fished” to “sustainable” between 2013 and 2014. This classification of ‘sustainable’ contrasts with much of the data for the fishery: (1) CPUE has decreased by 14% from 2012, reduced 8% between 2013 and 2014 and, in 2014, was amongst the lowest values on record and 1% below the historically low mean through the 1980s; (2) declines in CPUE were spatially consistent; (3) the proportion of large greenlip harvested has declined despite their market preference and higher price; (4) recent low survey densities of recruits in the two most important SAUs (Anxious Bay and The Gap); (5) lack of stock recovery at Ward Island, Flinders Island and Hotspot despite minimal recent catches; and (6) four of the six most important SAUs were assigned a red risk of overfishing category (highest risk). These data indicate fishing pressure is too high, with the potential to cause recruitment overfishing. However, there was less certainty in determining whether the stocks are recruitment overfished. Consequently, the WZ Greenlip Abalone Fishery is classified as ‘transitional depleting’ under the NFSRF. This was a change in the classification of these stocks from 2013 (‘sustainable’) and reflects the recent wide-spread deterioration in stock abundance.

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Stobart et al. 2015 Western Zone Greenlip Harvest Strategy Report

REFERENCES Flood, M., Stobutzki, I., Andrews, J., Begg, G., Fletcher, W., Gardner, C., Kemp, J., Moore, A., O'Brien, A., Quinn, R., Roach, J., Rowling, K., Sainsbury, K., Saunders, T., Ward, T. and Winning, M. (2012). Status of key Australian fish stocks reports 2012. Canberra. Fisheries Research and Development Corporation.

PIRSA (2012). Management Plan for the South Australian commercial Abalone Fishery. Adelaide. Primary industries and Regions South Australia Fisheries and Aquaculture. http://www.pir.sa.gov.au/__data/assets/pdf_file/0004/12982/Abalone_Fishery_Management_Pla n_-_September_2012_.pdf 85pp.

Stobart, B., Mayfield, S., Dent, J., Matthews, D. J. and Chick, R. C. (2012). Western Zone Abalone (Haliotis rubra and H. laevigata) Fishery (Region A). Fishery Stock Assessment Report to PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences). Adelaide. SARDI Publication No. F2007/000561-4. SARDI Research Report Series No. 660. 118pp.

Stobart, B., Mayfield, S., Dent, J. and Matthews, D. J. (2014). Western Zone Greenlip Abalone (Haliotis laevigata) Fishery. Fishery Stock Assessment Report to PIRSA Fisheries and Aquaculuture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No F2014/000373-1. SARDI Research Report Series No. 796. 67pp.

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