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Xiphias gladius

Method of production - Caught at sea
Capture method - Longline
Capture area - South East and Eastern Central Pacific (FAO 77,87)
Stock area - North East Pacific
Stock detail - All Areas
Certification -
Fish type - Oily fish

Sustainability rating Click for explaination of rating

This fish, caught by the methods and in the area listed above, is not a good choice of sustainable fish to eat and should be only eaten very occasionally. Click on the rating icon above to read more and on the alternatives tab below to find more sustainable fish to eat.

Sustainability overview

The last stock assessment for swordfish in the Eastern Pacific Ocean was undertaken in 2014. This revealed that whilst the population is at healthy levels, the fishing mortality has increased in recent years and is now likely above long-term sustainable levels. The 2012 catch of 9,910t was a historical record and nearly twice the estimated Maximum Sustainable Yield (MSY). Swordfish in the region is primarily taken in mixed longline fisheries operated by Japan, Spain, China, Taiwan and Korea with lesser amounts taken by Belize, Mexico, Chile, French Polynesia, Peru, Vanuatu, and the United States. A small proportion is caught in harpoon fisheries which are very selective. Bycatch of vulnerable species including seabirds, sharks and turtles remains of concern in the longline fisheries, and whilst there are measure to reduce this, monitoring and reporting is deficient in many fisheries. Buy swordfish from fisheries that are well regulated by their flag state to ensure that bycatch mitigation devices are being employed and monitored.

Commercial buyers in particular should establish what measures the flag state is taking to improve these deficiencies and specify the need for ongoing and demonstrable improvements. Large buyers should consider supporting such improvements.


Swordfish is the only member of the family Xiphiidae. It is a highly migratory species, moving towards temperate or cold waters in summer to feed and returning to warmer waters to spawn. They are apex predators that feed opportunistically. Squids and fishes are major prey items. In the Atlantic, spawning takes place in spring in the southern Sargasso Sea. In the Pacific, spawning occurs during spring and summer, and in the Mediterranean between June-August. Usually solitary, it forms large schools during spawning. A fast growing fish, swordfish begin to mature at two years of age, when they are about 150 to 170 cm in length, and by age four all are mature. They can attain a maximum size of 4.5m and a weight of 650kg. Swordfish tolerate temperatures of about 5 to 27C, but their optimum range is about 18 to 22C, and larvae have been found only at temperatures exceeding 24C.

Stock information

Stock area
North East Pacific

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Stock information
Swordfish stocks in the northern East Pacific Ocean are managed by both the Inter-American Tropical Tuna Commission (IATTC) and the Western and Central Pacific Fisheries Commission (WCPFC) and assessed by the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (ISC). In recent years, catches of swordfish in the region have reached a historic peak and have averaged approximately 9,700t between 2010 and 2012. The last stock assessment was carried out in 2014 and revealed that Maximum Sustainable Yield (MSY) was approximately 5,490t - considerably less than recent catches. Whilst the assessment indicated that the biomass is in a healthy state (Spawning Biomass, SB, at 1.87SBmsy), the recently observed fishing mortality, F, is too high in the long term (F at 1.11Fmsy proxy) and overfishing is likely occurring.


As for tuna, individual swordfish stocks range across and are accessed by numerous coastal states, making harmonised and effective management of these individual stocks very difficult. As a result, intergovernmental Regional Fisheries Management Organisations (RFMOs) have been established. There are five main tuna RFMOs worldwide and it is their responsibility to carry out data collection, scientific monitoring and management of these fisheries, including swordfish. Whilst the RFMOs are responsible for the development of management and conservation measures, the degree to which they are implemented, monitored and enforced still varies significantly between coastal states. The Western and Central Pacific Fisheries Commission (WCPFC) and the Inter-American Tropical Tuna Commission (IATTC) in the east share this responsibility for this fishery. The main countries reporting swordfish catches in this region are: Japan, Spain, China, Taiwan and Korea with lesser amounts taken by Belize, Mexico, Chile, French Polynesia, Peru, Vanuatu, and the United States.

There is no Total Allowable Catch (TAC) set for this stock. As recent catches are nearly twice the estimated MSY, management measures to limit catches should be considered to ensure the sustainability of the stock in the long-term. Management measures that apply to directed tuna fisheries, in particular albacore and bigeye, are expected to also benefit swordfish stocks. For countries fishing in the WCPFC area, participating coastal states are expected to have set TACs which are not to exceed the maximum level reported in any one year between 2001 and 2006.

The IATTC & WCPFC require 5% observer coverage on longliners greater than 20m.

To help address IUU, the IATTC and WCPFC maintain an IUU Vessel List; maintains a register of authorised fishing vessels; and prohibits transhipments at sea for most vessels (Some exemptions apply) and requires most other transhipments to be documented and observed as part of the regional observer programme.

Capture information

In the northern East Pacific Ocean, swordfish are mostly caught in mixed species longline fisheries. The largest catches have been taken by Japan for more than five decades, yet since the 90s, Spain, Korea, Taiwan and China have significantly increased their catches. These five countries are now responsible for 90% of the total catch which has recently peaked at 9,700t.

Pelagic longlining for tuna and billfish is associated the bycatch of vulnerable sharks, seabirds and marine turtles. To address this, both the IATTC and the WCPFC require a number of mitigation measures. Longliners must use one or more of the following, depending on vessel size and fishing location: weighted branch lines, night setting, tori lines, side setting with a bird curtain and weighted branch lines, blue-dyed bait; deep setting line shooter; management of offal discharge. WCPFC is beginning a project in 2017 to estimate seabird mortality. WCPFC Scientific Committee research in 2016 into sea turtle mitigation in longline fisheries found that interaction rates are lower when large circle hooks are used, higher at hooks closest to floats and higher when squid baits are used. Current measures relating to turtles include: the use of circle hooks for shallow set gear to reduce turtle capture, along with the requirement to carry line cutters and de-hookers and to promptly release turtles or to foster to recovery any sick or comatose turtles captured. Shark measures include: full utilisation of permissible sharks and retention of no more than 5% of fins to total shark weight; a prohibition to land silky and oceanic whitetip sharks; and countries to develop national plans of action to address the bycatch of sharks, turtles and seabirds. WCPFC prohibits the use of wire leaders and lines running directly off the longline floats or drop lines - known as shark lines; and for fisheries specifically targeting sharks, WCPFC countries are required to develop management plans, demonstrating how they intend to avoid or reduce catches of highly depleted shark species. In 2016 IATTC adopted a resolution to prohibit retention, transshipment, landing or storing of silky sharks caught by purse seine vessels. They also introduced stricter monitoring and reporting of catches of shark species. Data on the effectiveness of the WCPFC ban on shark finning is very limited. In 2016, WCPFC adopted measures to improve recording of manta and mobula rays discarded and released, and to treat these species as key shark species for assessment and research.

Monitoring and reporting of interactions with vulnerable species is deficient in many fisheries however, and the effectiveness of these various measures has not been evaluated. The IATTC and WCPFC both require 5% observer coverage on longliners greater than 20m.

Read more about capture methods

Froese, R. and D. Pauly. Editors. 2016. FishBase. Available at [Accessed Dec 2016].

IATTC, 2016. Active IATTC and AIDCP resolutions and recommendations. Available at [Accessed Dec 2016].

IATTC, 2016. Fishery status report no. 14: tunas, billfishes and other pelagic species in the Eastern Pacific Ocean in 2015. La Jolla, California, 2016. Available at [Accessed Dec 2016].

ISC, 2016. Report of the sixteenth meeting of the international scientific committee for tuna and tuna-like species in the North Pacific Ocean: plenary session. Sapporo, Hokkaido, Japan, 13-18 July 2016. Available at [Accessed Dec 2016].

ISSF, 2016. Status of the world fisheries for tuna: Management of tuna stocks and fisheries, 2016. ISSF Technical Report 2016-14.International Seafood Sustainability Foundation, Washington, D.C., USA. Available at [Accessed Nov 2016].

WCPFC, 2014. Western and Central Pacific fisheries commission scientific committee: summary report. Tenth regular session. Majuro, Republic of the Marshall Islands, 6-14 August 2014. Available at [Accessed Dec 2016].

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