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Blacklip Abalone is harvested in NSW, SA, TAS and VIC, with twelve management zones. Stocks are sustainable in six zones, depleting in two zones, depleted in two zones, undefined in one zone and negligible in one zone.

There are substantial difficulties in applying classical stock assessment models to abalone resources, given the possibly large number of stocks in each fishery, and that stock structure in abalone depart substantially from dynamic pool assumptions required by integrated models. In some regions Haliotis rubra rubra also displays spatially variable growth rates and maturity curves. All jurisdictions therefore rely on indicators and empirical performance measures. Primarily these are commercial catch and catch per unit effort (CPUE; as kg of abalone harvested per hour). but they can also include commercial catch per area searched (CPUA), and metrics derived from fishery independent surveys, and commercial and fishery-independent size composition.   CPUE and similar indicators from individual fishing events are relevant locally but are not indicative of status broadly [Parma et al. 2003], and status of the many populations within a management unit cannot be assumed to be trending in the same direction. Thus, it is only the average CPUE across each spatial reporting unit that provides the broader perspective for fishery assessment. Fishery assessment is usually based on a combination of indicators, and some jurisdictions combine the indicators to give a combined score for stock status. The annual catch by Blacklip Abalone fisheries is generally close to the established total allowable commercial catches (TACCs), with little over-catch or under-catch of the TACC. 

New South Wales Spatial Management Unit 1

The New South Wales Abalone Fishery is managed at spatial scales below that of the whole state. A state-wide total allowable commercial catch (TACC) is determined, and management arrangements, including those to spatially partition the TACC, are applied at different levels, typically at the scale of four geographically defined Spatial Management Units (SMUs) or among finer spatial scale reporting areas, that together aggregate to SMUs. Included in these arrangements are a commercial catch limit (within the TACC) for SMU 3 and 4, above which the SMUs are closed to commercial fishing (NSW 2023), and differences in minimum legal length (MLL) in the different SMUs. TACC’s were reduced from 333 t p.a. to 75 t p.a. over a decade to 2009-10, increased to 130 t over 5 years to 2015 and was reduced to 100 t p.a. in 2018, where it has been maintained. Assessments of fishery and stock performance are done at the scale of SMU and rely on fishery-dependent data from commercial fisher logbooks, including catch (whole weight, tonnes), catch rate (whole weight, kg per hour) and mean weight (catch divided by the number of abalone harvested) and from GPS logger data integrated with data from logbooks, including measures of legal-size biomass density (kg per hectare) and productive area of reef (i.e. cumulative area fished in the most recent three years) to estimate legal-size biomass.   

Fishery-dependent data including, catch, catch rate and legal-size biomass have informed recent changes in stock status and, together with substantial contrast to historical levels, provide information to infer historical status, reference levels of catch rate and a relative measure of stock abundance through time. Temporal trends in state-wide fishery performance, particularly catch rate and legal-size biomass, are similarly reflected at the spatial scale of SMUs, although at different absolute levels i.e., catch rates were at or among historically low levels during the mid-2000s, increasing through 2010, reaching at or among peaks between 2014 to 2016 and declining to 10-year minimums between 2018 to 2019. However, there is no formal harvest strategy describing reference points from which stock status can be directly defined at the SMU scale.

A state-wide minimum legal length (MLL) for blacklip abalone of 100 mm was introduced for the commercial fishery in 1972, increased to 108 mm (1980), 111 mm (1986) and then to 115 mm (1987) and 117 mm (2008) for both the commercial and recreational fishing sectors. The minimum legal length for the commercial fishery increased further to 118 mm (2018) and 120 mm (2019) in SMU 1, 2, and 3, and 120 mm (2010) to 123 mm (2013) to 125 mm (2018) in SMU 4.  

SMU 1

Catches declined from >15 t p.a. to <5 t p.a. over the decade from 2000 to 2010, whilst catch rate increased from historically low levels (<20 kg per hour) during the 5 years to 2005-06, to peaks of about 40 kg per hour between 2013 and 2014. Since 2020, low annual catches (1-3 t p.a.) with variable and recently low catch rates (<30 kg per hour) provide little evidence of sustained recovery or stability of stocks [ACN 2023] and even show signs of continued stock decline with relatively low levels of fishing mortality [TAFC 2023]. 

Catch from SMU 1 has typically contributed ≤10 percent of the total annual catch over at least the last 12 years. Stocks in SMU 1 were subject to high fishing mortality through the mid-1980s to the early-1990s (250 t reported in 1984 [ACN 2023]), then further depleted by mortality associated with infection by the protistian parasite, Perkinsus sp., from the 1990s to the early-2000s [Liggins and Upston 2010, TACSRC 2015]. The combination of fishing and mortality associated with Perkinsus suggested stocks in a large proportion of SMU 1 were depleted to less than 10% of virgin abundance [Liggins and Upston 2010]. SMU 1 was closed to all fishing in 2002 [ACN 2023] and areas were reopened over subsequent years, supporting a structured fishing survey of stocks that suggested stocks remained heavily depleted in many areas whilst there were some areas of less depleted stock [ACN 2023, Worthington 2010]. 

On the basis of the evidence provided above, the NSW Spatial Management Unit 1 stock is classified as a depleted stock.

New South Wales Spatial Management Unit 2

SMU 2

Catch from SMU 2 peaked at 230 t in 1983, was >100 t in 2000 and declined to 30-40 t p.a. following reductions in the state-wide TACC (see general text in SMU 1) and, within the last five years, has averaged 29 t p.a. and been at or among historically low levels [ACN 2023]. Further, following moderate MLL changes and state-wide TACC reductions there has been spatial contraction of fishing to the south of SMU 2, with relatively low and sporadic annual catch in the northern half of the SMU. 

During this time catch (47 t) and catch rate (~45 kg per hour) peaked in 2015-16, before catch rates dropped sharply, to ~35 kg per hour in 2017-18, catch generally declined, to a low of 16 t in 2020 and has averaged 26 t over the last 3 years. Between 2019 and 2022 catch rates have been relatively stable (~40 kg per hour), at higher MLLs, whilst legal-size biomass density has declined 8% per year [ACN 2023]. 

Declining and low catches together with increasing MLL and smaller numbers of heavier individual abalone being harvested at stable catch rate and a recent declining index of legal-size biomass suggest stock productivity has reduced. Further, during 2016 a large storm event significantly impacted north-east facing, shallow coastal reefs throughout NSW resulting in large areas of disturbed and damaged habitat, loss of abalone stock and coincided with sharp declines in catch rate and estimates of legal-sized biomass throughout SUM 2 in the following 2-3 years [ACN 2023]. Together with the spatial contraction of fishing to the southern, more productive areas of SMU 2, catches are generally below industry targets and patterns of fishery-dependent indicators of stock abundance suggest stocks throughout SMU 2 are not rebuilding well in response to management changes introduced over the last 5 years, including TACC reduction and MLL increases. 

On the basis of the evidence provided above, the NSW Spatial Management Unit 2 stock is classified as a depleting stock.

New South Wales Spatial Management Unit 3

SMU 3

Catch from SMU 3 peaked at 140 t in 1983, was >80 t between 1999-2001 and declined to 30-50 t p.a. following reductions in the state-wide TACC (see general text in SMU 1). Since 2005, catch (~50 t), catch rate (<50 kg per hour) and legal-sized biomass density peaked between 2014-16, before dropping sharply from late 2016, with catch rate to a low of ~37 kg per hour in 2018 and legal-size biomass density reaching a low in 2019. Catch rate subsequently increased to ~50 kg per hour in 2020 and declined in 2021 (43 kg per hour) and 2022 (41 kg per hour) [ACN 2023]. The June 2016 storm event impacted a large area (Green Cape) of SMU 3, resulting in habitat damage and loss of abalone stocks and contributed to low measures of fishery and stock performance. Within SMU 3, in response to the loss of stock there was a concentration of catch to areas (Disaster Bay) less affected in the immediately succeeding years, which was reversed from 2018, with relatively high catch rates through to 2020. Subsequent levels of catch from both Green Cape and Disaster Bay have declined sharply, to historically low levels, whilst catch rates have been maintained or increased. Catches in other Areas of SMU 3 have increased, to above industry defined target levels in many years, and catch rates in these areas have declined within the last few years, suggesting fishing mortality is too high to maintain levels of catch. Further, within SMU 3 the 3-year trend in catch rate and legal-sized biomass, used to inform recent status, is declining [ACN 2023].

Recent trends in measures of fishery and stock performance together with loss of stock from extreme storm events in 2016 and the responsive substantial changes in the distribution of catch, generally maintaining SMU level catches from largely reduced areas over the subsequent years, and with that trend being maintained in more recent years, with higher than proposed target catches at recently declining catch rates demonstrates stocks in SMU 3 were recently overfished after the 2016 storm and fishing pressure is too high in areas supporting current high catches. 

On the basis of the evidence provided above, the NSW Spatial Management Unit 3 stock is classified as a depleting stock. 

New South Wales Spatial Management Unit 4

SMU 4

Catch from SMU 4 peaked at 80 t in 1985-86, was 71 t in 2002 and declined to 20-40 t p.a. following reductions in the state-wide TACC. From 2009-10, when the TACC was at its lowest (75 t) and the minimum legal length in SMU 4 was raised to 120 mm (see general text in SMU 1) catch reached a historic low (14 t) before increasing to a recent peak of 40 t in 2017 (TACC 130 t). During this same period of time catch rate generally increased, reaching a peak of ~65 kg per hour in 2015 and legal-sized biomass density peaked in 2017. Catch, catch rate and legal-sized biomass declined through 2018-19 (TAC 100 t), before catch rates and legal-size biomass increased as catch remained relatively low (20 t) in 2020. Catch and catch rates increased through 2021, before declining marginally in 2022 whereas legal-sized biomass continued to decline over this period. 

Within the last 3-4 years, these SMU-wide patterns have been driven by levels of catch in Areas within SMU 4 that have been at or substantially exceeded industry defined target levels, with this partially in response to a shift in fishing away from areas in SMU 3 that were more substantially impacted by the 2016 storm and where measures of fishery performance were indicating declines. These recent levels of catch, from Areas within SMU 4, have however been taken at or among record high catch rates (>60 kg per hour) and have resulted in a 3-year increasing trend in catch rate throughout the SMU. However, these high catches have resulted in estimates of legal-sized biomass that have declined from among historically high levels to a 4-year low in 2021-22, producing a 3-year declining trend in legal-sized biomass in SMU 4. The contrast in recent measures of catch rate and estimates of legal-sized biomass provide some uncertainty in determination of a stock status. Recent historically high catches (within the period of the current 100 t TACC and 125 mm minimum legal length) harvested at historically high catch rates support a status determination of sustainable at levels above what would be considered reasonable target levels. However, measures of legal-sized biomass have been declining over the last 3 years, which increases the uncertainty associated with this determination. The persistence of catches above recent high average levels and at record high catch rates would suggest stock productivity increases in this SMU inconsistent with even recent estimates of surplus production within this SMU [ACN 2023], other areas of the NSW Abalone Fishery and other Australian jurisdictions and may suggest factors other than stock abundance influencing these measures of performance. Greater certainty in the determination of stock status would be made where there was stability in the level of catch through time and consistency among changes in measures of catch rate and legal-size biomass.

On the basis of the evidence provided above, the NSW Spatial Management Unit 4 stock is classified as a sustainable stock.

Blacklip Abalone biology [Shepherd 1973, Officer 1999, Tarbath et al. 2001, Tarbath and Officer 2003]

Distribution of reported commercial catch of Blacklip Abalone

New South Wales – Indigenous (Management Methods) https://www.dpi.nsw.gov.au/fishing/aboriginal-fishing

Victoria – Indigenous (Management Methods) A person who identifies as Aboriginal or Torres Strait Islander is exempt from the need to obtain a Victorian recreational fishing licence, provided they comply with all other rules that apply to recreational fishers, including rules on equipment, catch limits, size limits and restricted areas. Traditional (non-commercial) fishing activities that are carried out by members of a traditional owner group entity under an agreement pursuant to Victoria’s Traditional Owner Settlement Act 2010 are also exempt from the need to hold a recreational fishing licence, subject to any conditions outlined in the agreement. Native title holders are also exempt from the need to obtain a recreational fishing licence under the provisions of the Commonwealth’s Native Title Act 1993.

Commercial catch of Blacklip Abalone - note confidential catch not shown

1. Abalone Council of NSW, 2023, Assessment of abalone stocks in NSW: Submission to the TAC setting process for 2023-24, Sydney.
2. Bell, JD 2020, Abalone Recruitment Monitoring — Preliminary investigation of Abalone Recruitment Modules in the Eastern Abalone Zone. Victorian Fisheries Authority Science Report Series No. 13. 13pp.
3. Burnell, O. and Hogg, A. (2023). Assessment of the Southern Zone Abalone (Haliotis rubra and H. laevigata) Fishery in 2022/23. Fishery Assessment Report to PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2007/000552-9. SARDI Research Report Series No. 1179. 59pp.
4. Burnell, O. and Mayfield, S. (2023). Assessment of the Central Zone Abalone (Haliotis laevigata & H. rubra) Fishery in 2021. Report to PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. FXXXXXX. SARDI Research Report Series No. XXXX. XXpp.
5. Dixon, CD, Lowe, J. and Potts, J. 2022, Stock Assessment for the Eastern Zone of the Victorian Abalone Fishery 2021/22. MRAG Asia Pacific, Brisbane, Australia. 87 pp.
6. Dixon, CD, Lowe, J. and Potts, J. 2023, Stock Assessment for the Central Zone of the Victorian Abalone Fishery 2021/22. MRAG Asia Pacific, Brisbane, Australia. 93 pp.
7. Gorfine, H, Bell, J, Mills, K, Lewis, Z 2012, Removing sea urchins (Centrostephanus rodgersii) to recover abalone (Haliotis rubra) habitat. Department of Primary Industries, Queenscliff, Victoria, Australia.
8. Helidoniotis F and Haddon M 2014, Modelling the potential for recovery of Western Victorian abalone stocks: The Crags. Interim Report to 2012/225. CSIRO, Hobart.
9. Internal Report: East Coast Abalone Assessment
10. Jones, HJ, Tarbath, D & Gardner, C 2014. Could harvest from abalone stocks be increased through better management of the size limit/quota interaction? Australian Seafood Cooperative Research Centre, Institute for Marine and Antarctic Studies, University of Tasmania, Australian Seafood Cooperative Research Centre, Institute for Marine and Antarctic Studies, University of Tasmania, 2014
11. Lafferty KD, Harvell CD, Conrad JM, Friedman CS, Kent ML, Kuris AM, Powell EN, Rondeau D and Saksida SM, 2015, Infectious Diseases Affect Marine Fisheries and Aquaculture Economics Annual Review of Marine Science, 7: 471–496.
12. Liggins G and Upston J 2010. Investigating and managing the Perkinsus-related mortality of Blacklip Abalone in NSW. Final report to the Fisheries Research and Development Corporation for Project No. 2004/084. Industry & Investment – Fisheries Final Report Series No. 120. Cronulla, NSW, Australia. 182pp.
13. Management Plan for the South Australian Commercial Abalone Fisheries (2021), 51pp.
14. Mayfield, S, McGarvey, R, Gorfine, HK, Peeters, H, Burch, P and Sharma S 2011, Survey estimates of fishable biomass following a mass mortality in an Australian molluscan fishery. Journal of Fish Diseases 2011; 34: 287–302.
15. Modelling trends including effects of natural disturbance in an abalone dive fishery in Australia. Natural Resource Modelling, 31. DOI: 10.1111/nrm.12175
16. Mundy C and Jones H 2017, 'Tasmanian Abalone Fishery Assessment 2016', Technical report, Institute for Marine and Antarctic Studies Report. University of Tasmania, Hobart, 163.
17. Mundy, C and McAllister J 2020, Tasmanian Abalone Fishery Assessment 2019. Institute for Marine and Antarctic Studies Report. University of Tasmania, Hobart.
18. Mundy, C and McAllister J 2023, Tasmanian Abalone Fishery Assessment 2022. Institute for Marine and Antarctic Studies Report. University of Tasmania, Hobart.
19. New South Wales Government Gazette. Number 147 – Mining and Primary Industries. Friday, 31 March 2023.
20. NSW Total Allowable Catch Setting and Review Committee. 2015. Report and Determination 2016 – Abalone Fishery. New South Wales Government.
21. NSW Total Allowable Fishing Committee. Abalone Fishery. Determination for the 2023/24 fishing period. 14 April 2023.
22. Oliver, ECJ, Benthuysen, JA, Bindoff, NL, Hobday, AJ, Holbrook, NJ, Mundy, CN and Perkins-Kirkpatrick SE 2017, The unprecedented 2015/16 Tasman Sea marine heatwave, Nature Communications 8, 1–12.
23. Oliver, ECJ, Lago, V, Hobday, AJ, Holbrook, NJ, Ling SD and Mundy CN 2018, 'Marine heatwaves off eastern Tasmania: Trends, interannual variability, and predictability', Progress in Oceanography 161, 116–30.
24. Parma, AM, Orensanz, JM, Elías I and Jerez, G 2003, Diving for shellfish and data: incentives for the participation of fishers in the monitoring and management of artisanal fisheries around southern South America, in Newman, SJ, Gaughan, DJ, Jackson, G, Mackie, MC, Molony, B, St John, J and Kailola, P eds, 'Australian Society for Fish Biology Workshop Proceedings - Towards Sustainability of Data-Limited Multi-Sector Fisheries'. 8–29.
25. Shepherd, SA 1973, 'Studies on southern Australian abalone (genus Haliotis) I. Ecology of five sympatric species', Australian Journal of Marine and Freshwater Research 24, 217–257.
26. Size limits and yield for Blacklip Abalone in northern Tasmania. TAFI Technical Report Series, No 17. University of Tasmania, pp37.
27. Size limits for Greenlip Abalone in Tasmania. TAFI Technical Report Series, No 5. University of Tasmania, pp48.
28. Status of the Central Zone Abalone Fisheries in 2022. Status Report for PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. FXXXXXXX. SARDI Research Report Series No. XXXX. XXpp.
29. Stobart, B. (2023). Western Zone Blacklip Abalone (H. rubra) and Greenlip Abalone (Haliotis laevigata) Fisheries in 2022/23. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. XXXXXX. SARDI Research Report Series No. XXX. XX pp.
30. Stobart, B. and Mayfield, S. (2021). Western Zone Blacklip Abalone (Haliotis rubra) and Greenlip Abalone (H. laevigata) Fisheries in 2020/21. Report to PIRSA Fisheries and Aquaculture (PDF 7.7 MB). South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2017/000331-5 SARDI Research Report Series No. 1119. 72pp
31. Stobart, B., Mayfield, S. and Heldt, K. (2019). Western Zone Blacklip Abalone (Haliotis rubra) and Greenlip Abalone (H. laevigata) Fisheries in 2018. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2017/000331-3. SARDI Research Report Series No. 1039. 90pp.
32. Stobart, B., Mayfield, S. and Heldt, K. 2020. Western Zone Greenlip Abalone (Haliotis laevigata) and Blacklip Abalone (H. rubra) Fisheries in 2019. Report for PIRSA Fisheries and Aquaculture. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI publication in review. 84. pp.
33. Tactical Research Fund: Developing the use of existing technology in cost-effective and reliable Industry-based structured fishing surveys to urgently replace more costly methods and advise finer-scale management of abalone populations. FRDC Project 2008-076.
34. Tarbath, D and Gardner C 2011, Tasmanian Abalone Fishery Assessment 2010. Tasmanian Aquaculture and Fisheries Institute.
35. Tarbath, D and Mundy C 2004, Tasmanian Abalone Fishery 2003. Tasmanian Aquaculture and Fisheries Institute.
36. VFA 2017a, 2016/17 Victorian Abalone Stock Assessment – Central Zone. Victorian Fisheries Authority Science Report Series No. 2. Victorian Government: Melbourne, 56 pp.
37. VFA 2017b, 2016/17 Victorian Abalone Stock Assessment – Eastern Zone. Victorian Fisheries Authority Science Report Series No. 3. Victorian Government: Melbourne, 43 pp.
38. VFA 2017c, 2016/17 Victorian Abalone Stock Assessment – Western Zone. Victorian Fisheries Authority Science Report Series No. 4. Victorian Government: Melbourne, 48 pp.
39. Victorian Department of Natural Resources and Environment. 1996. Draft abalone management plan. Victorian Fisheries Program. The Department of Natural Resources and Environment: Melbourne.
40. Western Abalone Divers Association, 2023. Assessment of abalone stocks in Western Zone Victoria: Submission to the TAC setting process for 2023-24