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.

Global swordfish stock statuses range from unlikely overfished to unknown, with degrees of stock status uncertainty varying from low to high. When averaged, international swordfish stocks are ‘moderate’ conservation concern.

Although there are limited data regarding international pelagic longline bycatch levels and trends, the continued bycatch of sea turtles, seabirds, marine mammals,
sharks, billfish, and other pelagic fishes remains a ‘critical’ conservation concern for the majority of swordfish fleets. In the absence of data demonstrating that bycatch rates are declining, SeaChoice must adopt the precautionary approach in considering the severity of the
bycatch problem in global longline fisheries.

Pelagic longlines have negligible habitat effects since they are not used near the bottom. The ecosystem effects of removing large predators, such as tuna, billfishes, and sharks, however, remain controversial. Due to the nature of the ecosystem effects caused by the removal of large predators from the ecosystem, the conservation concern for pelagic longlines is ‘moderate’.

International swordfish management ranges from effective measures in the U.S. that include a bycatch management plan, monitoring, fishery data collection and other measures. However, these measures were put in place only after a significant decline in North Atlantic swordfish populations. Management in other parts of the world ranges from highly effective as in the south Pacific managed by the Hawaiian state government to ineffective in the south Atlantic. Overall this category is a ‘moderate’ conservation concern.

How was this swordfish caught? Where was this swordfish caught?

Consumption advisory due to mercury.

No.