Lamna nasus

WHAT TO LOOK FOR
This is a heavy bodied shark with a short, conical snout, and long gill slits. It has a strong keel on its caudal peduncle with short, secondary keels on the base, and a crescent tail.

 

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COLOR

Dark grey or blackish on top, with the underside being white with dusky blotches. It has a very distinctive white tip on its first dorsal fin.

SIZE
The shark is 1.9 to 2.6 ft [60 to 80 cm] long at birth. Porbeagle sharks are extremely slow to reach sexual maturity (18 to 26 years). Males mature at 4.9 to 6.7 ft [1.5 to 2 m] in length, and females mature at 6.7 to 8.2 ft [2 -2.5 m] (but can be smaller in the south Pacific). Its maximum length can be over 9.8 ft [300 cm].

HABITAT
Inshore to continental offshore fishing banks. They are occasionally in the open ocean, from less than 3.3 to 2296.6 ft [1 to 700 m] deep.

DISTRIBUTION
The sharks are found in the north Atlantic, and cool water areas 33.8 to 64.4ºF [1 to18ºC] in the southern hemisphere. They are not found in equatorial seas.

BIOLOGY:
Prey – Small fishes, dogfish, tope and squid.
Reproduction – Porbeagle sharks have long gestation periods, and generally bear litters of only 4 pups.

BEHAVIOR
This is a migratory species that moves inshore and to the surface in the summer months. It spends the winter offshore in deeper water. Populations are segregated by age (size) and sex. The shark is inquisitive, and may approach boats and divers.

STATUS
The porbeagle shark is Critically Endangered in the Northeast Atlantic and Mediterranean where fisheries are unmanaged. The Mediterranean population has virtually disappeared. It is Endangered n the Northwest Atlantic — female spawning stock has decreased to 12% and 16% of previous levels. In the Southern Ocean it is classed as Near Threatened –depletion of spawning stock indicates biomass is 18% of previous levels. The North Atlantic population has been seriously depleted (~90%) by commercial fisheries for the shark’s high value meat.

In 2007, at CITES CoP14, Germany proposed the porbeagle shark for Appendix II, but the proposal failed to achieve the 2/3rds majority vote required for the listing. In 2009, the International Commission for the Conservation of Atlantic Tunas (ICCAT/ICES specialist meetings) recommended that high-seas fisheries stop targeting porbeagle sharks. In 2010, at CITES CoP15, the species was again proposed for Appendix II by Sweden on behalf of European Union Member States and Palau, and although the United Nations Food and Agriculture Organization (FAO) determined that the porbeagle shark met the criteria for an Appendix II listing, the proposal was defeated by Japan and its cohorts.