Yellowfin Tuna

• Commonwealth Eastern Tuna and Billfish Fishery (1,378t in 2021)

Yellowfin tuna is a highly migratory species, fished throughout its range in the tropical regions of the Pacific, Indian and Atlantic Oceans. The Amber ‘Eat Less’ ranking is the result of an assessment of the eastern fishery that catches the majority of yellowfin tuna in Australian-managed waters. The Australian catch of yellowfin tuna is less than 1% of the total catch in the Western Pacific region, with the vast majority of the catch coming from other countries fishing on the high seas.

Recent information suggests that there may be a number of different stocks of yellowfin tuna across the east coast area fished by the Australian fishery. This is currently not considered in the management of the fishery, although there are no indications that these stocks are overfished at present.

Yellowfin tuna are caught using longlines in Australian waters, which also catch a range of threatened species. Independent Video monitoring across the fishing fleet was rolled out in 2015. This welcome progress provides confidence in reporting of wildlife affected by the fishery.

However, video monitoring has identified that fishers were significantly under-reporting how much endangered wildlife was killed in the past, which means that the impact of this fishery is substantially higher than previously thought. Since cameras have been installed on boats, the number of turtles, seabirds, whales and dolphins recorded as caught has significantly increased.

Despite this, most current management arrangements for the ecological risks of the fishery to endangered species is based on unreliable information collected before the implementation of cameras, though there is now seven years of reliable, recent data available to the fishery. This does not represent sustainable management, and will result in the red-listing of this fishery in future if not urgently addressed.

The catch of turtles in particular has increased over the past decade. From 2018-2021, an average of 122  turtles were caught per year, compared to the 4-16 that were reported as caught annually in the three years before video monitoring was mandated on the fishing vessels. In previous years, a ‘trigger limit’ was in place which required fishery managers to take action if the rate of turtle catch exceeded a certain level. This trigger limit has since been removed, which means there are no measures in place to cap the number of turtles caught in the tuna fishery.

Of particular concern; the ETBF has reported bycatch of between 20-68 critically endangered leatherback turtles per year since 2018. There are only 1000 mature nesters thought to be left in the population impacted by the ETBF, and it is declining at around 6% annually. For context, and demonstrating adequate management, a US-managed longline fishery that impacts the same leatherback turtle population is closed when yearly bycatch reaches 16 leatherbacks. If not for lower leatherback catch since 2020, the fishery was likely to have been red-listed. Immediate implementation of measures to reduce leatherback turtle bycatch to safe levels is required to avoid a red-listing in future.

In contrast, better protection arrangements and obligations on the fishery to protect seabirds have resulted in additional management that should effectively reduce the impact of the fishery. This is welcome.

Turtles, whales, dolphins and seabirds are at risk from multiple threats, including fishing. Given the small scale of the Australian tuna fishery relative to international tuna fisheries, it is unlikely that this fishery is the major driver of on-going population declines in these species of endangered wildlife.

Commonwealth marine parks were established in 2018, but in a form significantly delayed and weakened following sustained Australian tuna fishing industry lobbying. As such they confer only a fraction of the protection for threatened and endangered species of original government proposals.

• Imported from Indian Ocean, Western & Central Pacific Ocean stocks,

Yellowfin tuna is a highly migratory species, fished throughout its range in the tropical regions of the Pacific, Indian and Atlantic Oceans. Trade records indicate Australia imported 318t of fresh, frozen and chilled (not including canned) tuna in 2011-12 from Fiji, Indonesia, the Maldives and NZ, but no detail of species imported or where the fish was caught is provided. Therefore it is not possible to provide specific advice on individual fisheries and the red ‘Say No’ ranking is the result of an assessment of the main way in which yellowfin tuna are fished and general stock status in the Western and Central Pacific and Indian Oceans.

In general, there is some concern from fisheries scientists that stocks in the Pacific Ocean are already overfished and current high levels of fishing are likely to cause further depletions in yellowfin tuna stocks.

Yellowfin tuna caught in the Pacific and Indian Oceans is taken using longlines, gillnets and purse seines associated with Fish Aggregating Devices (FADs). FADs are artificial objects that float on the surface of the ocean and exploit the natural tendency of fish and other marine wildlife to aggregate under floating objects. The bycatch of large numbers of sharks, including whale sharks, and turtles has been well documented in FAD-associated fisheries. Longlining and gillnetting is also responsible for the capture of threatened sharks, turtles and seabirds. Sharks are often targeted for the high value of their fins, a practice that is increasing in many tuna longline fisheries that catch yellowfin tuna. Scientists have assessed that tuna longlining has contributed to population declines of a number of shark species worldwide.

The countries that manage the fisheries generally do not monitor the bycatch caught, and independent observer coverage is low to non-existent.

• Commonwealth Western Tuna and Billfish Fishery (18t in 2020)

Yellowfin tuna is a highly migratory species, fished throughout its range in the tropical regions of the Pacific, Indian and Atlantic Oceans. More than 90% of the Australian catch of yellowfin tuna is from a fishery operating along the eastern coastline. The smaller catch from the western coastline is assessed here.

It is highly likely that the stock of yellowfin tuna caught caught off western Australia is overfished, and international fishing pressure in the wider Indian Ocean is still set too high to allow the stock to recover. As the Australian portion of the catch is small, it is unlikely that fishing in Australian waters is driving the decline in the population.

Yellowfin tuna are caught using longlines in Australian waters, which also catch a range of threatened species. In previous years, fishery observers undertook independent monitoring of the impact of fishing on endangered wildlife. Video monitoring across the fishing fleet was rolled out in 2015. This welcome advance provides high confidence in reporting of wildlife affected by the fishery.

However, video monitoring has identified that fishers were significantly under-reporting how much endangered wildlife has been killed in the fishery in the past, which means that the impact of this fishery is likely higher than previously thought.

Since cameras have been on boats the number of turtles, seabirds, whales and dolphins caught has increased. Given the relatively small scale of this fishery, it is unlikely that it is driving decline in the populations of these species, or preventing their recovery. However, it is expected that management measures are put in place to ensure that marine wildlife bycatch reduces over time.

Commonwealth marine parks, provide a degree of protection to endangered wildlife. However, it is notable that sectors of the tuna fishing industry secured significant reductions in the area protected from fishing in offshore western Australian waters.