Swordfish

Swordfish in the south west Pacific Ocean is not overfished and not subject to overfishing.

This stock is assessed and managed by the Western and Central Pacific Fisheries Commission (WCPFC). Fishing for this stock began in the 1950s and catches increased to a peak in 2012 of around 11,000 tonnes. They have since declined to around 7,000t. The last stock assessment was carried out in 2021, using data up to 2019. The next assessment is expected in 2025.

Spawning biomass (SB) is estimated to have gradually declined from the 1950s to the mid-1990s before rapidly declining to an overall low point in around 2010. Stock size in 2019 is close to this level, at 39% of unfished levels. However, it is thought to be around 3 times the level associated with Maximum Sustainable Yield (SB MSY). Therefore, the stock is not in an overfished state.

Fishing mortality (F) is predicted to have increased gradually through the mid-1990s and sharply increased in the early-2000s. It appears to have stabilized at high levels in the last decade. However, it remains below the MSY level, at 47% of FMSY in 2019. Therefore, the stock is not subject to overfishing.

There are no projections for the stock. The Maximum Sustainable Yield is estimated to be 9,543 tonnes, and catch in 2019 was around 7,700t.

Few appropriate management measures are in place for south west Pacific Ocean swordfish. Management measures only cover part of the fishery, and do not prevent overexploitation. Observer coverage, which is important for ensuring accurate data on catch and bycatch, is too low.

Tuna and swordfish are highly migratory species, found on the high seas and in numerous countries' waters. This makes harmonised and effective management challenging. Regional Fisheries Management Organisations (RFMOs) are responsible for monitoring and managing these stocks on behalf of the countries that access them. However, the degree to which management is implemented, monitored and enforced by each country varies significantly. It is important that commercial buyers choose swordfish that has been caught by vessels that are well regulated by their flag state.

This stock is assessed and managed by the Western and Central Pacific Fisheries Commission (WCPFC). Some stocks overlap with the Inter-American Tropical Tuna Commission (IATTC). The IATTC and WCPFC endeavour to work together to promote compatibility between their respective conservation and management measures across the Pacific, but this is not always achieved.

The main management measure for this stock is a freeze on fishing effort and catches to 2000-2006 levels. However, this only applies to an area south of 20 degrees S, which is only responsible for 42% of catches. This leaves half of the fishery effectively unmanaged. In addition, the measure does not include limits on the total fishing mortality on the stock, and so is insufficient to prevent overexploitation. Scientific recommendations are that these two issues be addressed. The Maximum Sustainable Yield is estimated to be 9,543 tonnes, and catch in 2019 was around 7,700t. It is unclear how this compares to 2000-2006 levels.

The movement and aggregation behaviours of swordfish make it particularly vulnerable to local depletion. There may also be connectivity between the south western population and south eastern population. The south eastern population has no management and no stock assessment since 2011.

Most swordfish is caught by longlining. Since 2011 only 5% observer coverage has been required on large longliners, considered by the scientific committee to be too low for accurate data: a minimum of 20% coverage is recommended. In addition, data recorded by longliners is considered inadequate for scientific purposes and minimum data standards must be identified and introduced.

To help address IUU, the WCPFC maintains an IUU Vessel List, prohibits transhipments at sea between purse seiners (some exemptions apply) and requires all other transhipments to be documented and 100% observed as part of the regional observer programme. In 2017 a Compliance Monitoring Scheme was introduced to assess and improve compliance with obligations, and penalise non-compliance.

A small amount of swordfish in the south west Pacific Ocean is caught by gillnetting. This receives a default red rating owing to the very high levels of cetacean and turtle bycatch.

In the South-West Pacific Ocean, swordfish are mostly caught in mixed species longline fisheries. Much smaller quantities of swordfish are taken in artisanal gill or fixed net fisheries. Gillnets used for catching tuna and tuna-like species can be 7km long and are known for extremely high bycatch including turtles, whales, dolphins, whale sharks, mobulids, requiem sharks and sunfish. WCPFC bans the use of gillnets over 2.5km long, but monitoring is poor. There is no available data on bycatch by gillnet fisheries in the WCPO

Gillnetting is known to have significant levels of seabird bycatch, with an estimated 400,000 birds being killed each year, globally. Some of the highest bycatch rates are in the northwest Pacific.

The five marine turtle species in the WCPFC Convention Area (green, hawksbill, leatherback, loggerhead and olive ridley) are vulnerable, endangered, or critically endangered, and WCPFC does not have enough data to assess the threat posed by fisheries. There are some mitigation measures, including requirements for safe handling and release.

In 2020, an estimated 1.7 million sharks were caught as bycatch or had an interaction with WCPO fisheries. Of these, around 34,000 individuals were caught in FAD-free purse seines, 60,000 in FAD-associated purse seines, and 1.6 million by longlining. Bycatch species include bigeye thresher, shortfin mako, and silky. Of greatest concern is oceanic whitetip shark, which is in a severely overfished state and critically endangered. Further catch mitigation and improved handling and release practices are required. Mobulid rays are also bycaught, but there is very little data on these species.

Interactions between cetaceans and WCPFC fisheries have been recorded, with most resulting in the animal being released alive. Species include false killer whales, toothed whales and oceanic dolphins. These interactions are not well recorded and the scale of impact is unclear.