Source: Patterson, H, Bromhead, D, Galeano, D, Larcombe, J, Woodhams, J and Curtotti, R 2021, Fishery status reports 2021, Australian Bureau of Agricultural and Resource Economics and Sciences, Canberra. CC BY 4.0.
The SESSF continues to be managed in accordance with the Southern and Eastern Scalefish and Shark Fishery Management Plan 2003. The fishery has seven sectors that are managed through a combination of input and output controls including limited entry, catch limits, spatial closures, size limits and catch-and-effort triggers that are used to initiate further analysis and assessment. The SESSF sectors include:
Commonwealth South East Trawl Sector
East Coast Deepwater Trawl Sector
Great Australian Bight Trawl Sector
Scalefish Hook Sector*
Shark Hook Sector*
Shark Gillnet Sector*
*collectively called the Gillnet Hook and Trap Sector.
Analysis of Performance
Performance – status of fish stocks
The table above shows that there are several SESSF stocks that are considered to be overfished. Most of these stocks overlap jurisdictional boundaries, meaning they are caught in a combination of Commonwealth and state fisheries, complicating management. AFMA continues to work with State agencies to pursue complementary arrangements in overlapping fisheries.
Stock assessments were updated in 2020 for a number of SESSF species. Assessments for gummy shark, ocean perch (offshore), ribaldo, royal red prawn and sawshark estimated the current biomass, or a proxy thereof, to be above the target reference point. Assessments for blue-eye trevalla, mirror dory (east/west), oreos (mixed), school whiting, and silver trevally estimated that the current biomass, or a proxy thereof, is between the limit reference point and the target referent point. For species assessed as being between the limit and target reference points, catches are set at a level that will allow the stock to build to the target. Smooth oreo (other) continues to be assessed based on the outputs of the 2019 ERA, as well as recent catch and effort data, which shows recent fishing mortality is sustainable.
John dory was assessed using a weight of evidence approach, including the outputs of two data-poor assessment methods, which estimated the stock had declined over time, however it is not clear what the current estimate of biomass is. As a precautionary approach, AFMA implemented a TAC based on unavoidable catches for the 2021-22 fishing season, and will consider further analysis of the catch and effort data when setting a TAC for the 2022-23 fishing season.
Commonwealth rebuilding strategies are in place for blue warehou, eastern gemfish, redfish, school shark and orange roughy. Each of these strategies implement incidental total allowable catches and management arrangements to prevent targeting and promote recovery of the stock to the limit reference point. The performance of the strategies are reviewed annually by the relevant resource assessment group, and each undergo a thorough review every five years. Five-year reviews of the orange roughy and blue warehou rebuilding strategies were completed in 2021, and the revised rebuilding plans are expected to be published in late 2021.
A five-year review of the Upper-slope Dogfish Management Strategy was also completed in 2021, with the revised management strategy expected to be published in late 2021. The management strategy differs slightly from the rebuilding species, in that it prohibits retention and relies on an extensive closure network to support the rebuilding of the stocks to above the limit reference point.
The stock assessment for eastern redfish estimated that the current biomass remains below the limit reference point. Redfish continue to be managed in accordance with the objectives of the rebuilding strategy, which include setting a bycatch TAC to allow for incidental catches. AFMA will commence the five-year review of the redfish rebuilding strategy in 2021 to ensure the management arrangements, including monitoring and research, remain effective.
Performance – economic returns
AFMA reports against economic key performance indicators using the key commercial stocks in each fishery. The Commonwealth Fisheries Harvest Strategy Policy defines what is meant by key commercial stocks. In the 2020-21 season, there were 11 key commercial species in the SESSF with MEY targets: Bight redfish, blue eye trevalla, blue grenadier, deepwater flathead, eastern school whiting, gummy shark, orange roughy east, pink ling west, pink ling east, school shark and tiger flathead.
Three of those species, tiger flathead, deepwater flathead and eastern school whiting are assessed as being ‘on target’ or within 20 per cent of their target reference point on average over the past five years. Two stocks – orange roughy east and pink ling east – are between the limit reference point and target reference point and heading towards the target. One stock – gummy shark – is assessed as being above the target reference point and heading towards the target. Three stocks – Bight redfish, blue grenadier and pink ling west – are assessed as being above the target reference point but not heading towards the target. One stock – blue-eye trevalla – is assessed as being between the limit and target reference point but not heading towards the target. School shark is assessed as being below the limit reference point; however, the latest assessment using Close-Kin Mark-Recapture genetic methods indicates that the stock had recovered slightly during the period from 2000-2017.
Performance – reliability of information
Logbook reporting of retained and discarded catch by shark gillnet, shark hook and scalefish hook boats continues to be monitored by comparing logbook recorded catch and discards against EM reviews. Reporting by fishers has improved since the introduction of EM, particularly for quota species.
In June 2021, AFMA engaged ABARES to undertake an independent analysis comparing logbook data with EM collected data for retained and discarded commercial and bycatch as well as protected species interactions in the GHAT. The analysis is expected to be completed in 2021-22. The outcome of this analysis will assist AFMA and its stakeholders understand the reliability of both sources of information as an accurate representation of commercial fishing operations and inform consideration of EM program audit rates.
A trial was recently completed to better understand the ability of EM to provide information on catch and effort data in the Commonwealth Trawl Sector. The final report, which is available on the AFMA website, concludes that based on the configuration of cameras during the trial, EM can detect interactions with large TEPs, presence/absence of discarded catch and whether mitigation devices are being deployed, however was unable to identify species composition or provide weight estimates for retained and discarded catch. Given the Commonwealth Government’s recent funding announcement to enhance and expand the EM program across Commonwealth fisheries, the utility of EM in Commonwealth trawl fisheries will be considered amongst a suite of other data collection and monitoring options to ensure a cost-effective approach for the fishery.
As a result of the COVID-19 pandemic, deployment of on-board observers was restricted during the second and third quarters of 2020 which affected data collection in the trawl sectors of the SESSF. Coverage recommenced in October 2020 and sampling targets have mostly been achieved since then. Biological data collection in the GHAT is collected via an industry-led program and was also impacted by the COVID-19 pandemic, although sample collection targets were mostly achieved for 2020-21.
The SESSF RAG will review the SESSF Data Plan in August 2021 to ensure data collected across the fishery, including through the observer program, continues to provide useful inputs to stock assessments and support management decisions.
A seismic oil and gas survey was completed during the first six months of 2020 in Bass Strait, which impacted Danish seine catch rates for tiger flathead and school whiting. The impact of the seismic surveys and the lack of observer data collected during this period will be considered by the relevant RAG when reviewing fishery indicator data and undertaking stock assessments in 2021.
Performance – status of bycatch
The ERAs undertaken for the following methods and sectors of SESSF were considered and accepted by the relevant RAGs and management advisory committees in 2019 and 2020:
Otter board trawl method in the Commonwealth Trawl Sector
Danish seine method in the Commonwealth Trawl Sector
Otter board trawl method in the Great Australian Bight Trawl Sector
Shark gillnet method in the Gillnet Hook and Trap Sector.
The remaining SESSF ERAs (including the scalefish automatic longline, and shark hook and scalefish hook methods of the Gillnet Hook and Trap Sector) are being undertaken by CSIRO and are expected to become available later in 2021.
Under these ERAs there were 21 individual species assessed across the sectors as potentially being at high risk for the period 2012-16. These consisted of 14 species in the Commonwealth Trawl Sector (otter board trawl and Danish seine), one species in the Great Australian Bight Trawl Sector (also high risk in the Commonwealth Trawl Sector), and seven species in the gillnet sector of the Gillnet Hook and Trap Sector. Management responses are currently under consideration. In particular, through the development of bycatch and discarding work plans for the relevant sectors, with a view to be finalised later in 2021.
To monitor potential changes in risk in between updates to ERAs, SESSFRAG developed an annual checklist of risk related triggers in August 2020. This annual checklist will be used to identify if an update to an ERA should be brought forward.
Industry is currently coordinating a project to develop a seal mitigation device for otter board trawl boats that will close the trawl net to stop the ingress of seals when the net is being hauled. Good progress has been achieved to date with a half-scale prototype developed and tested in a flume tank, and further development including full-scale design for extensive at-sea trials planned for 2021-22.
AFMA continues to focus on minimising seabird interactions in the SESSF by monitoring compliance with boat-specific Seabird Management Plans. AFMA are also working with industry to develop mitigation options to further reduce seabird interactions with otter board trawl boats by providing feedback on designs and ultimately assessing whether proposed approaches meet the requirements for an exemption to the biological material retention requirements introduced in 2019-20.
The following species/stocks continue to be subject to rebuilding strategies: blue warehou, eastern gemfish, upper-slope dogfish, orange roughy, redfish and school shark. The status of the rebuilding strategies are:
a revised blue warehou stock rebuilding strategy is in the final stages of development following the 2019 five-year review. The existing strategy continues to be implemented while the strategy is being finalised
a five-year review of the eastern gemfish stock rebuilding strategy commenced in late 2020 with a view to have the review finalised in late 2021
a comprehensive review of the Upper-Slope Dogfish Management Strategy was completed in 2020-21. It is planned that the revised strategy will be finalised in late 2021. A monitoring program has commenced that will establish the baseline relative abundance of dogfish and support monitoring through time
a revised orange roughy stock rebuilding strategy is in the final stages of development following the 2019 five-year review. The existing strategy continues to be implemented while the strategy is being finalised
a five-year review of the redfish stock rebuilding strategy is due to commence in late 2021
a five-year review of the school shark rebuilding strategy is underway and due to be completed in 2021-22.
An implementation workplan for the SESSF Strategic Monitoring and Review Project (SMARP, FRDC 2014-203) and Declining Indicators Project (FRDC 2016-146) was finalised in early 2020. The workplan prioritises the recommendations from each project, including approaches for future monitoring and assessment options and developing additional or alternative indicators for use in future assessments and harvest strategies.
Key to the implementation workplan is the ongoing work to develop a new SESSF harvest strategy (FRDC 2018-021) which will consider alternative approaches to multi-species harvest strategies, including monitoring and assessment options identified in the SMARP project.
AFMA commissioned an independent expert panel to review the new stock assessment approach, Close Kin Mark Recapture (CKMR), for school shark in 2020-21. Overall the Expert Panel concluded that the CKMR approach to assess school shark is likely to be the most appropriate method to understand the status of the population and to make management decisions. The Panel also identified several key areas for further work prior to the next assessment to improve the accuracy and precision of assessment outcomes. The outcomes of the review have been adopted by the Shark RAG and AFMA, and actions to address key uncertainties will be undertaken prior to the next assessment in 2024.
No external reviews were completed during 2020-21.