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The Porbeagle (Lamna nasus) is a large pelagic predatory shark.
Distribution
The Porbeagle's distribution ranges from the northwestern coast of North America, from New Jersey to Greenland and from the northwesten coast of Africa, Marocco or Western sahara and the Mediterranean, and up to the waters off Iceland to the north coast of Norway and the northwestern coast of Russia. In the southern hemisphere it's distribution is circumglobal from 30o to 60o south.
Habitat
The porbeagle is mainly a pelagic shark, but can be found in coastal waters. It lives in cold water commonly from about 5oC to 10oC, but have been found down to 1oC and up to 23oC. It can be found at the surface to more than a depth of more than 700 meters.
Anatomy and appearance
The most distinguishing characteristic of Lamna nasus is its white patch on trailing edge of the dorsal fin, this distinguishes it from both the Salmon shark and the Great white shark and it's two keels on the tail fin, this is common with the Salmon shark.
The porbeagle is a stout big and heavy shark, dark blue-gray on top and white underneath, it has a conical snouth.
The porbeagle can grow up to about 3.7 m (12 feet), weighing about 160-250 Kg (350-550 pounds).
Diet
The porbeagle is an opportunistic feeder, it eats mostly bony fish like mackrels, herring lancetfish and sauries.
Reproduction
The porbeagle is ovoviviparous. Gestation period is about 8 to 9 months. Litters of up to 6 pups have been recorded but the normal size is about 4. Pups are about 60 to 80 cm long when born. Female porbeagles reaches sexual maturity at about 12 to 13 years and males at 7 to 8 years.
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