Queensland Spanner Crab Fishery: Commercial quota setting for June 2016 – May 2018

The Queensland (QLD) fishery for spanner crabs primarily lands live crab for export overseas, with gross landings valued around A$5 million per year. Quota setting rules are used to assess and adjust total allowable harvest (quota) around an agreed target harvest of 1631 t and capped at a maximum of 2000 t. The quota varies based on catch rate indicators from the commercial fishery and a fishery independent survey. Quota management applies only to ‘Managed Area A’ which includes waters between Rockhampton and the New South Wales (NSW) border. This report has been prepared to inform Fisheries Queensland (Department of Agriculture and Fisheries) and stakeholders of catch trends and the estimated quota of spanner crabs in Managed Area A for the forthcoming annual quota periods (1 June 2016–31 May 2018). The quota calculations followed the methodology developed by the crab fishery Scientific Advisory Group (SAG) between November 2007 and March 2008. The QLD total reported spanner crab harvest was 1170 t for the 2015 calendar year. In 2015, a total of 55 vessels were active in the QLD fishery, down from 262 vessels at the fishery’s peak activity in 1994. Recent spanner crab harvests from NSW waters average about 125 t per year, but fell to 80 t in 2014–2015. The spanner crab Managed Area A commercial standardised catch rate averaged 0.818 kg per net-lift in 2015, 22.5% below the target level of 1.043. Compared to 2014, mean catch rates in 2015 were marginally improved south of Fraser Island. The NSW–QLD survey catch rate in 2015 was 20.541 crabs per ground-line, 33% above the target level of 13.972. This represented an increase in survey catch rates of about four crabs per groundline, compared to the 2014 survey. The QLD spanner crab total allowable harvest (quota) was set at 1923 t in the 2012-13 and 2013-14 fishing years, 1777 t in 2014-15 and 1631 t in 2015-16. The results from the current analysis rules indicate that the quota for the next two fishing years be retained at the base quota of 1631 t

Queensland Spanner Crab Fishery : Commercial quota setting for June 2015 – May 2016

The Australian fishery for spanner crabs is the largest in the world, with the larger Queensland (QLD) sector’s landings primarily exported live overseas and GVP valued ~A$5 million per year. Spanner crabs are unique in that they may live up to 15 years, significantly more than blue swimmer crabs (Portunus armatus) and mud crabs (Scylla serrata), the two other important crab species caught in Queensland. Spanner crabs are caught using a flat net called a dilly, on which the crabs becoming entangled via the swimming legs. Quota setting rules are used to assess and adjust total allowable harvest (quota) around an agreed target harvest of 1631 t and capped at a maximum of 2000 t. The quota varies based on catch rate indicators from the commercial fishery and a fishery-independent survey from the previous two years, compared to target reference points. Quota management applies only to ‘Managed Area A’ which includes waters between Rockhampton and the New South Wales (NSW) border. This report has been prepared to inform Fisheries Queensland (Department of Agriculture and Fisheries) and stakeholders of catch trends and the estimated quota of spanner crabs in Managed Area A for the forthcoming quota period (1 June 2015–31 May 2016). The quota calculations followed the methodology developed by the crab fishery Scientific Advisory Group (SAG) between November 2007 and March 2008. The total reported spanner crab harvest was 917 t for the 2014 calendar year, almost all of which was taken from Managed Area A. In 2014, a total of 59 vessels were active in the QLD fishery, the lowest number since the peak in 1994 of 262 vessels. Recent spanner crab harvests from NSW waters have been about 125 t per year. The spanner crab Managed Area A commercial standardised catch rate averaged 0.739 kg per net-lift in 2014, 24% below the target level of 1.043. Mean catch rates declined in the commercial fishery in 2014, although the magnitude of the decreases was highest in the area north of Fraser Island. The NSW–QLD survey catch rate in 2014 was 16.849 crabs per ground-line, 22% above the target level of 13.972. This represented a decrease in survey catch rates of 0.366 crabs per ground-line, compared to the 2013 survey. The Queensland spanner crab total allowable harvest (quota) was set at 1923 t in 2012 and 2013. In 2014, the quota was calculated at the base level of 1631 t. However, given that the 2012 fisheryindependent survey was not undertaken for financial reasons, stakeholders proposed that the total allowable commercial catch (TACC) be decreased to 1777 t; a level that was halfway between the 2012/13 quota of 1923 t and the recommended base quota of 1631 t. The results from the current analysis indicate that the quota for the 2015-2016 financial year be decreased from 1777 t to the base quota of 1631 t

Queensland Spanner Crab Fishery: Commercial quota setting for June 2016 – May 2018

The Queensland (QLD) fishery for spanner crabs primarily lands live crab for export overseas, with gross landings valued around A$5 million per year. Quota setting rules are used to assess and adjust total allowable harvest (quota) around an agreed target harvest of 1631 t and capped at a maximum of 2000 t. The quota varies based on catch rate indicators from the commercial fishery and a fishery independent survey. Quota management applies only to ‘Managed Area A’ which includes waters between Rockhampton and the New South Wales (NSW) border. This report has been prepared to inform Fisheries Queensland (Department of Agriculture and Fisheries) and stakeholders of catch trends and the estimated quota of spanner crabs in Managed Area A for the forthcoming annual quota periods (1 June 2016–31 May 2018). The quota calculations followed the methodology developed by the crab fishery Scientific Advisory Group (SAG) between November 2007 and March 2008. The QLD total reported spanner crab harvest was 1170 t for the 2015 calendar year. In 2015, a total of 55 vessels were active in the QLD fishery, down from 262 vessels at the fishery’s peak activity in 1994. Recent spanner crab harvests from NSW waters average about 125 t per year, but fell to 80 t in 2014–2015. The spanner crab Managed Area A commercial standardised catch rate averaged 0.818 kg per net-lift in 2015, 22.5% below the target level of 1.043. Compared to 2014, mean catch rates in 2015 were marginally improved south of Fraser Island. The NSW–QLD survey catch rate in 2015 was 20.541 crabs per ground-line, 33% above the target level of 13.972. This represented an increase in survey catch rates of about four crabs per groundline, compared to the 2014 survey. The QLD spanner crab total allowable harvest (quota) was set at 1923 t in the 2012-13 and 2013-14 fishing years, 1777 t in 2014-15 and 1631 t in 2015-16. The results from the current analysis rules indicate that the quota for the next two fishing years be retained at the base quota of 1631 t

Total allowable commercial catch review for Queensland spanner crab (Ranina ranina), with data to December 2021

This report was prepared to inform on estimated Total Allowable Commercial Catch (TACC) of spanner crabs and potential economic Gross Value of Production (GVP) in managed area A for the forthcoming two quota years 1 July 2022 to 30 June 2023 and 1 July 2023 to 30 June 2024. The harvest strategy uses standardised commercial (sCPUE) and fishery independent survey (sFIS) catch rates from two years, compared against target rates, to calculate TACC. The average 2020–2021 catch rate indicators from two years, standardised using generalised linear models, were: sCPUE = 0.823 kilograms per dilly-net lift and sFIS = 6.623 crab per ground-line. The stock indexes were the ratio of the indicators compared to their targets. The calculated stock indexes were less than 1, signalling catch rates were below target: sCPUE ratio = 0.6 and sFIS ratio = 0.631. The pooled index was 0.616 (average of the two stock indexes). The pooled index means that the fishery was at 62% of its target. By referencing the pooled index against the harvest strategy, no change in the 847 t TACC was suggested. This TACC corresponded to a potential GVP of around $8 million per year if fully caught

Stock assessments of bream, whiting and flathead (Acanthopagrus australis, Sillago ciliata and Platycephalus fuscus) in South East Queensland

Yellowfin bream, sand whiting and dusky flathead are major target species for both commercial and recreational fishers in south east Queensland. Their fishery and regional social and economic importance prompted stock assessments to inform on the sustainability of fishing. The assessments covered both estuarine and ocean-beach waters between Baffle Creek north of Bundaberg and Coolangatta on the Gold Coast. Over the last five years (2013 to 2017), the South East Queensland total harvest for yellowfin bream, sand whiting and dusky flathead averaged 242, 272 and 121 tonnes per year respectively. The catches split for bream was 54 per cent commercial versus 46 per cent recreational, 77 per cent commercial versus 23 per cent recreational for whiting and 36 per cent commercial versus 64 per cent recreational for flathead. The stock assessments used commercial, recreational, charter and indigenous catch, and research data. Inputs to the model included fish harvest sizes (1945 to present), standardised catch rates from commercial net logbook data (1988 to present), and fish age–length data collected from the fishery (2007 to present). All three assessments were challenging due to lack of contrast in the data since the commercial logbook system began in 1988. All three species had been subject to high harvests prior to that year, and commercial catch rates had not varied much since then. In addition, the only available catch rates came from net fishing, which can target whole schools of fish. Net catch rates may be ‘hyperstable’ and not sensitive to trends in fish population size. Bream biomass was estimated to be at 33.8 per cent of unfished biomass. The equilibrium maximum sustainable yield (MSY) was estimated as 420 tonnes per year (commercial and recreational sectors combined, and Moreton and Fraser regions combined). The model indicated that maintenance of a harvest size of 220 t ⁄ yr will recover the biomass to 60 per cent of unfished in about 25 years. A lower harvest of 150 t ⁄ yr would recover to 60 per cent in about 12 years. Whiting biomass in 2017 was estimated as 28.7 per cent of unfished biomass, which is approximately the biomass corresponding to MSY (denoted BMSY). The model’s estimate of equilibrium MSY was 452 t ⁄ yr. Current combined harvest size is approximately equal to the equilibrium harvest at 60 per cent unfished biomass (B60). Rebuilding of the stock from its current level to B60, however, would require the harvest to be reduced, ideally to about 150 t (commercial and recreational sectors combined, and Moreton and Fraser regions combined) to rebuild within about five years. Yearly harvests between 150 and 270 t ⁄ yr would recover the stock more slowly; the midpoint 210 t ⁄ yr would reach B60 in about seven years. The status of flathead is more uncertain than bream and whiting. The precautionary estimate of dusky flathead biomass in the Moreton region in 2017 was between 36 per cent and 39 per cent of unfished spawning biomass, approximately equal to or slightly below BMSY. The estimated MSY was 104 t ⁄ yr to 112 t ⁄ yr, approximately equal to current harvests. Recovery of the spawning stock to 60 per cent in the Moreton region would require the harvest to be reduced, ideally to 63 t ⁄ yr (commercial and recreational sectors combined, Moreton region only) which would recover to B60 within eight years. An intermediate harvest level of 73 t ⁄ yr would reach B60 within 16 years. In the Fraser region, fishing pressure on flathead was lower, and 2017 estimated spawning biomass was 70 per cent of unfished. Although the results for flathead are already precautionary, additional caution may be needed in view of fishing club catch rates which date back to the 1950s and indicate that flathead were already heavily fished by 1988

The AusTED II, an improved trawl efficiency device 2. Commercial performance

An Australian-designed bycatch reduction device (BRD), known as the AusTED, was modified to improve its efficiency and simplify its design. The modified version (the AusTED II) was tested under a range of conditions typical of prawn trawl fisheries of north eastern Australia. Trials occurred during commercial trawling operations to heighten industry awareness of research into BRDs and improve the credibility of research results to industry. Average bycatch reduction ranged between 15% and 49% depending upon fishery conditions, and the capture of large animals such as stingrays and sea turtles was significantly reduced. The AusTED II had a variable effect on prawn catches depending on trawling conditions, ranging from no significant difference to a 36% loss. The AusTED II offers commercial fishers the benefits of large animal exclusion plus reduced bycatch. Reductions in bycatch were explained in part by the exclusion of fish species with “fusiform” and “laterally compressed” body-forms. Unexpectedly, “weak swimming fish” were also excluded consistently by the AusTED II. The trialing of a single BRD across a range of trawling conditions in north eastern Australia demonstrated the variability in BRD performance that can be attributed mainly to the quantity and composition of bycatch species. It is highly likely that other exclusion systems like the AusTED II will not be immediately suitable to all north east Australian trawl fisheries. The acceptance of BRDs by the Australian trawling industry will depend upon efficient and pragmatic designs coupled with industry confidence in research results

The AusTED II, an improved trawl efficiency device 1. Design theories

Improvements to the original AusTED (Australian trawling efficiency device) design were completed in 1994 and the device was renamed AusTED II. New design features, theories and performance of the AusTED II during testing are described. The AusTED II reduced bycatch (including large animals) and slightly reduced byproduct. Variations in prawn catches were dependent on the area being fished. Large fluctuations in net drag precluded any detailed analysis of changes in drag as a result of fitting the AusTED II to standard commercial trawl gear. The AusTED II equipped net required no extra assistance or vigilance from the crew when tested under commercial conditions

Reducing Prawn-trawl Bycatch in Australia: An Overview and an Example from Queensland

Prawn trawling occurs in most states of Australia in tropical, subtropical, and temperate waters. Bycatch occurs to some degree in all Australian trawl fisheries, and there is pressure to reduce the levels of trawl fishery bycatch. This paper gives a brief overview of the bycatch issues and technological solutions that have been evaluated or adopted in Australian prawn-trawl fisheries. Turtle excluder devices (TED's) and bycatch reduction devices (BRD's) are the principal solutions to bycatch in Australian prawn-trawl fisheries. This paper focuses on a major prawn-trawl fishery of northeastern Australia, and the results of commercial use of TED's and BRD's in the Queensland east coast trawl fishery are presented. New industry designs are described, and the status of TED and BRD adoption and regulation is summarized. The implementation of technological solutions to reduce fishery bycatch is assumed generally to assist prawn-trawl fisheries within Australia in achieving legislative requirements for minimal environmental impact and ecological sustainable development