Porbeagle Sharks (Lamna nasus)


CITES Status | Taxonomy | Description | Habitat | Distribution | Threats

 

CITES Status

Porbeagle Shark

Credit: NOAA

Proposed by Brazil, Comoros, Croatia, Denmark and Egypt for listing in Appendix II at CoP16.
Included by the European Union in Appendix III.

Taxonomy

Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Lamniformes
Family: Lamnidae
Genus: Lamna
Species: nasus

Description

Porbeagle sharks are moderately large, spindle-shaped sharks. They are characterized by a cylindrical body, conical head and crescent-shaped tail. A distinctive white patch on the lower trailing edge of the first dorsal fin is used to identify fins in trade. They are warm-blooded, relatively slow growing and late maturing, long-lived, and bear only small numbers of young.

Weight: about 300 pounds (135 kg)
Length: up to 11.5 feet (3.5 m)
Appearance:  dark bluish-grey backs with a white belly, they have a cylindrical body, conical head, and crescent-shaped tail
Lifespan: around 65 years
Diet: small fishes, sharks, squid
Behavior: females give birth to live young that are nourished in utero with egg yolk for about 8-9 months

In the northwest Atlantic, males mature at approximately 8 years and 5.5 feet (1.5 m) length while females mature at 13 years and 6.4 feet (2 m) length. Life history characteristics vary between stocks. Northeast Atlantic porbeagle sharks are slightly slower growing than the northwestern stock. Both northern stocks are much larger, faster growing, and have a shorter life span than the smaller, longer-lived (~65 years old) southern porbeagles. They are ovoviviparous (that is, they give birth to live young that are nourished in utero with egg yolk), and females produce an average of four young per year. Gestation is thought to last 8 to 9 months.

Habitat

The porbeagle shark is a coastal species found in the upper pelagic zone from the surface to 200 m deep (occasionally to 350 m-700 m). They are most commonly reported on continental shelves and slopes from close inshore (especially in summer), to far offshore (where often associated with submerged banks and reefs). They are apparently less abundant in the high seas. Stocks segregate (at least in some regions) by age, reproductive stage, and sex. They undertake seasonal migrations within their stock area.

Mature females tagged off the Canadian coast appear to migrate 1,240 miles (2,000 km) south to give birth in deep water in the Sargasso Sea in the Central North Atlantic. Pups seem to follow the Gulf Stream to return north.

Distribution

Porbeagle sharks are found worldwide in a band between ~30° and 60°S in the Southern Hemisphere and mostly between 30° and 70°N in the North Atlantic Ocean and Mediterranean. Genetic studies identified two isolated populations, in the North Atlantic and the Southern oceans.

Threats

  • targeted fisheries
  • shark fin trade
  • bycatch

This species is highly desired for the shark meat trade in Europe and some other areas. Fins are also moderately desirable in trade. They are caught in a variety of fisheries, including artisanal and small-scale commercial fisheries and commercial longline, gill net, drift net, and trawl fisheries. Sports fisheries exist in the U.S., New Zealand, and in some EU Member States.

Additional Information

Check out this fact sheet to learn more about porbeagle sharks. Also available in Arabic, French, Russian, and Spanish pdf.

The United States strongly supports shark and manta ray proposals and applauds the leadership of the proponent countries. What are the benefits of listing a marine species in CITES appendix II? Click here to learn more.

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