Southern Bluefin Tuna (SBT), Thunnus maccoyii are migratory fish, crossing the Pacific, Atlantic and Indian Ocean within their annual migration. Their habitat ranges widely across the southern hemisphere including territorial seas of Indonesia, Australia, New Zealand and South Africa. Every year between September and April, adult SBT (aged 11-12 years) migrate from southern feeding areas to their single identified spawning ground in the waters south of Indonesia. The larvae and juvenile fish are swept south by the Leeuwin current along the Western Australian coastline and reach the Great Australian Bight as 1 to 2 year-olds.
Southern Bluefin Tuna are generally long lived, with some fish living greater than 40 years. At maturity SBT can be up to 2 metres in length and weigh greater than 200kg. The age of maturity is a matter of debate; however, is generally agreed to be between 8 and 12 years of age. SBT are incredible predators of the ocean. They can accelerate at twice the rate of a Ferrari and have the capacity to swim long distances at speeds which are illegal on most urban roads. SBT are opportunistic feeders meaning they prey on a large variety of food including crustaceans, cephalopods and small pelagic fish.