Estimated Catch: 6,181.7 tonnes

Stock Status of Target Species

Source: Patterson, H, Williams, A, Woodhams, J and Curtotti, R 2019, Fishery status reports 2019, Australian Bureau of Agricultural and Resource Economics and Sciences, Canberra. CC BY 4.0.

MANAGEMENT PLANS/ARRANGEMENTS

The fishery continues to be managed in accordance with the Southern Bluefin Tuna Fishery Management Plan 1995. It is managed through a system of output controls in the form of individually transferable quotas, which are allocated as statutory fishing rights under the management plan. The performance criteria detailed in the management plan were all met in 2018-19.

The Commission for the Conservation of Southern Bluefin Tuna sets an annual global total allowable catch. From the global total allowable catch national allocations are provided to all members. Prior to the commencement of the fishing season (1 December to 30 November), AFMA determines a total allowable catch of southern bluefin tuna for the domestic fishery based upon Australia's national allocation.

The Southern Bluefin Tuna Fishery is an approved wildlife trade operation for the purposes of Parts 13 and 13A of the Environment Protection and Biodiversity Conservation Act 1999 until 13 December 2019.

ANALYSIS OF PERFORMANCE

Performance – quota setting

The domestic total allowable catch for the 2017-18 Southern Bluefin Tuna fishing season was 6165 tonnes. When undercatch from the previous season is added the effective total allowable catch becomes 6527 tonnes.

The AFMA Commission set the 2018-19 total allowable catch as 6165 tonnes after accepting an undertaking from the Australian Southern Bluefin Tuna Industry Association to voluntarily set aside 250 tonnes of the quota to account for other sources of mortality, including mortality from recreational fishing.

The total catch in the fishery, for the 2017-18 fishing season, was 6159 tonnes. Concession holders in the ranching sector of the fishery took approximately 83 per cent of the catch. The remaining catch was taken by longline.

The Commission for the Conservation of Southern Bluefin Tuna allows up to 20 per cent of any uncaught national allocation to be carried forward into the next fishing season. Australia advised that it would carry forward 118 tonnes of uncaught quota from the 2017-18 fishing season into the 2018-19 season.

Performance – status of fish stocks

The Commission for the Conservation of Southern Bluefin Tuna management procedure specifies that a full quantitative stock assessment should be undertaken every three years. The 2017 stock assessment suggested that the stock remains at a low state, estimated to be 13 per cent of the initial spawning stock biomass, and below the level to produce maximum sustainable yield.

There has been improvement since previous stock assessments, which indicated the stock was at 5.5 per cent of original biomass in 2011 and 9 per cent in 2014. The current fishing mortality rate is below the level associated with maximum sustainable yield meaning that overfishing is not currently occurring.

Internationally, the Commission for the Conservation of Southern Bluefin Tuna management procedure is considered a success in that it has been instrumental in addressing the previous sharp decline in the stock and facilitating recovery towards agreed targets.

Performance – economic returns

The majority of the southern bluefin tuna total allowable catch continues to be taken by the purse seine sector in South Australia, for subsequent grow out by the ranching sector. Historically the purse seine catch was taken in the Great Australian Bight south of Ceduna. However, in recent years the majority of the catch has been taken in areas to the east of Kangaroo Island. As these areas are closer to the aquaculture zone in Port Lincoln, the time the fish spend in the tow cage before transfer to farms has been reduced.

The amount of fish taken by longliners on the east coast depends primarily on access to available quota from the ranching sector and the seasonal availability of fish. In the 2017-18 fishing season 1034 tonnes was caught compared to 731 tonnes in the previous season.

EXTERNAL REVIEWS

A management procedure is a pre-agreed set of rules that can specify changes to the total allowable catch based on updated monitoring data. In 2011 the Commission for the Conservation of Southern Bluefin Tuna adopted a management procedure to guide its global total allowable catch setting. The management procedure is tuned to a 70 per cent probability of rebuilding the stock to the interim rebuilding target reference point of 20 per cent of the original spawning stock biomass by 2035.

The Commission for the Conservation of Southern Bluefin Tuna has decided to develop a new management procedure to guide the setting of total allowable catches from 2021. It will take into account changes in data availability, in particular, changing the recruitment monitoring series from an aerial survey of juveniles to a juvenile gene tag/recapture program.