Southern Bluefin Tuna


Latin name: Thunnus maccoyii


Common name: Tuna

  • Say No

Farmed

Region:
Australia

Key Facts

  • Southern bluefin tuna is mainly caught in purse seines; the majority are juveniles that are 'ranched' in sea cages off the coast of SA to marketable size.
  • Southern bluefin tuna is critically endangered species, with population numbers down to around 5% of original fish biomass.
  • The fishery is managed by an international collaborative body that includes representatives of the nations that fish the species. Management initiatives to protect the species have been difficult to implement, although progress is beginning to be made.
  • Southern bluefin tunas are top predators that require high amounts of wild-caught fish to grow to marketable size.

More information

  • Commonwealth Southern Bluefin Tuna Fishery (4,485t caught in purse seines in 2011-12)

Southern bluefin tuna is mainly caught in purse seines in Australian waters. The majority of southern bluefin tuna caught are juveniles, which are transported to large sea cages off South Australia and ‘ranched’ (grown on in fish farms) until they reach marketable size.

Southern bluefin tuna is listed as ‘Critically endangered’ on the IUCN Redlist due to intense fishing pressure from a number of nations, including Australia, Japan, Taiwan and New Zealand. Recent stock assessments indicate that the numbers of fish remaining are still at around 5% of their original population.

Southern bluefin stocks are managed internationally by a body that includes representatives of the fishing nations that fish the species (the Commission for the Conservation of Southern Bluefin Tuna).  Although there is now a plan in place that may enable the stock to rebuild over a period of decades, reaching agreement and reducing quotas has been challenging, given that individual fish fetch hundreds of thousands of dollars.

Southern bluefin tuna are top predators that have a high dependency on wild caught fish in ranching operations. Accessing information on the ranching process is difficult, but research reports suggest that it takes between 10-20kgs of wild caught fish to grow 1kg of Southern bluefin tuna. The majority of fish used to feed southern bluefin tuna comes from the sardine fishery managed by SA, which is Amber-listed in this guide as a result of dolphin mortalities.

The majority of southern bluefin tuna grown to marketable size are exported to Japan. There is a limited market in Australia.