Swordfish

Swordfish

Mekajiki, Kajiki-Maguro

Swordfish are found throughout the world’s oceans where surface waters are warmer than 13°C. The latitudinal range of Swordfish extends from approximately 50° North to 45° South. Swordfish are highly migratory and adults are found year-round in most parts of the distributional range, but in greatest abundance in areas of rich production where small pelagic prey are plentiful, such as frontal zones, merging currents, and temperature and salinity gradients. Swordfish reach a maximum total length 455 cm and a maximum weight of 650 kg, although individuals taken commercially in the Pacific are typically no longer than 120-190 cm. Females are larger than males, and nearly all specimens over 140 kg are female. Pacific swordfish are larger than western Atlantic swordfish, which grow to 320 kg, and Mediterranean swordfish, which are rarely over 230 kg. Swordfish are prolific egg producers; a large female can produce 30 million eggs annually and attain sexual maturity at 5-6 years of age. This species is known to live at least 9 years.

Swordfish are considered inherently resilient to fishing pressure because their populations grow relatively quickly. In addition, swordfish are characterized by an early to moderate age at first maturity, high growth rates, and moderate maximum age. Extremely high fecundity and a worldwide distribution also enable this species to support fishing pressure.

Based on the lack of a stock assessment for South Atlantic swordfish, this stock is ranked as unknown and is considered of ‘moderate’ conservation concern.

Based on the estimates of leatherback turtle bycatch in the South American gillnet fisheries, bycatch in these fisheries also ranks as a ‘critical’ conservation concern. Leatherbacks are considered a critically endangered species by the IUCN.

Drift gillnets have negligible habitat effects because they generally do not come into contact with the seafloor and so are of ‘low’ conservation concern.

International South Atlantic management is limited by lack of data for several swordfish fisheries and an incomplete stock assessment for the South Atlantic swordfish stock. There is no large-scale plan to reduce bycatch in South Atlantic swordfish fisheries and regulations are not enforced. Though the south Atlantic swordfish stock status is uncertain, existing size limits and quotas are unlikely to prevent decline. International management of swordfish in the South Atlantic is thus deemed ‘ineffective’.

How was this fish caught? Where was this fish caught?

Consumption advisory due to mercury.

No.