The SBT industry is an Australian success story, with international impact. The SBT industry, pioneered by the Port Lincoln fishing industry has gone from humble beginnings, to over-exploitation and accompanying species collapse, to one of innovation, resilience and a strong resource base. Today the SBT industry is sustainable, certified, is the single most valuable sector of South Australia’s aquaculture industry, and increasingly a significant target species for the East Coast Tuna and Billfish fishery.
The SBT industry began towards the end of World War II, in 1936, when Stanley Fowler from the Commonwealth Scientific Industrial Research Organisation (CSIRO) “hitched a ride” with a Royal Australian Air Force flight over the Great Australian Bight. Stanley Fowler was conducting a survey of tuna to stimulate economic development. Before this time the fishery was largely unappreciated and unexploited (Serventy, 1956). It was during this flight that Stanley Fowler spotted abundant schools of SBT migrating off the coast of SA.
In 1979 fishery biologists warned that the fishery was fully exploited. The parental biomass was found to be reducing at an alarming rate (30% of its pre-exploitation size), which would ultimately result in poor recruitment of juvenile SBT to the fishery in subsequent years. Furthermore, there was evidence that the overall global SBT catch was beginning to decline. Australian SBT catch peaked in 1982; however, at the same time the Japanese catch of 40,000 tonnes was half that of its peak in 1962. This highlights how overall the SBT stock was decreasing.
Upon realisation of the drastic effect that the tuna industry had on the species biomass, the industry changed its practices to support fishing for tomorrow, not just today. In 1984, Individual Transferable Quotas (ITQs) were allocated by the Australian Government to fishermen. ITQs were introduced to prevent further exploitation in the industry, allowing time for the species to recover. Japanese and New Zealand governments also agreed to limit catches. After introduction of the initial ITQs, they were further reduced. Between 1983 and 1988 fishermen were unable to catch even the lower quotas, demonstrating how much the fishery had been over-exploited.
Increasing development in technology allowed SBT to be frozen at minus 60C. At this temperature SBT can be frozen in prime condition as super-cooled freezing stabilises fats in flesh, preventing degradation. The SBT could now be transported to Japan in prime condition, marking the birth of the sashimi market. SBT went from being worth $2 per kilogram in cans to greater than $45 per kilogram as a premium culinary product.
It was originally the Japanese interest that proposed ranching of SBT. To assess the potential of growing out SBT in ranches (sea cages), a study was initiated by the Tuna Boat Owners Association of Australia (now called ASBTIA) and the Federation of Japan Tuna Fisheries Co-operative Associations in conjunction with the Overseas Fishery Cooperation Foundation (OFCF). The project was supported by the South Australian Government and the Australian Government and undertaken by the SBT industry in partnership with the Fisheries Research and Development Corporation (FRDC).
