Striped Marlin

• Commonwealth Eastern Tuna and Billfish Fishery (365t in 2024)

Striped marlin is found in the Pacific Ocean and caught throughout its range by fisheries managed by other nations, including Australia, Taiwan, Japan and the Republic of Korea.

The majority of striped marlin is caught as a byproduct in fishing targeting tunas off the eastern coastline of Australia, with a small catch (less than 1t) from the western coastline that is not covered by this assessment.
Stock status information indicates significant concern over the population of striped marlin caught in the ETBF, with evidence of high fishing activity and stock declines over a period of decades.

The stock fished by Australia is currently overfished, and as fishing pressure is set too high, overfishing can continue to drive a decline in the stock.
Striped marlin are caught using longlines in Australian waters, which also catch a range of threatened species. Turtles, whales, dolphins and seabirds are at risk from multiple threats, including fishing. It is imperative that cumulative impacts are considered, and that fisheries are precautionary when reacting to threatened species interactions.

Independent video monitoring across the fishing fleet was rolled out in 2015. This best practice management measure provides confidence in reporting of wildlife affected by the fishery. However, video monitoring identified significant under-reporting of deaths of endangered wildlife in the past.

Thanks to the now reliable bycatch data, managers have been able to identify several species at high risk from this fishery including turtles, albatrosses and marine mammals.

However, even after 10 years of reliable data, there has been no effective effort from industry or managers to protect most bycatch species.

Of particular concern, this fishery has reported bycatch of between 13-35 critically endangered leatherback turtles per year since 2020. There are only around 1400 mature nesters thought to be left in the population impacted by the fishery, and it is declining at around 6% annually.

In comparison, a US-managed longline fishery that impacts the same leatherback turtle population closes when yearly bycatch reaches 16 leatherbacks.

This fishery has been aware of these turtles being caught for several years and has made no significant changes to their operation.

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.

Marine sanctuaries, areas where fishing is not allowed, provide valuable protection to species, allowing for greater confidence in surrounding fisheries.

The Australian tuna fishing industry has extensively lobbied for the removal of marine sanctuary protection in areas where they want to fish. They have been successful on multiple occasions.

Marine sanctuaries are a fundamental part of healthy oceans, and their targeted reduction is not in the best interest of the ocean or the industry. This continued effort to undermine marine sanctuaries is a disappointing lack of environmental stewardship.