Hooded Seal

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{{Taxobox | color = pink | name = Hooded Seal | image = Klappmuetze.jpg | image_width = 200px | regnum = Animalia | phylum = Chordata | classis = Mammalia | ordo = Carnivora | familia = Phocidae | genus = Cystophora | genus_authority = Nilsson, 1820 | species = C. christata | binomial = Cystophora christata | binomial_authority = (Erxleben, 1777) }} The Hooded Seal (Cystophora christata) is an arctic seal found only in the central and western North Atlantic ranging from Svalbard in the east to the Gulf of St. Lawrence in the west.

1 Naming
2 The bulge
3 Size
4 Lifestyle
5 Breeding
6 Offspring
7 Lifespan
8 Facts
9 See also
10 External links

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Naming

The seal is named after a cap-like bulge essay on forehead and nose of the adult male that doesn’t hang down as with the elephant seal.

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The bulge

The bulge develops when the seal is four years old. The male can blow up this bulge, so that the size of its head seems to be twice as large.

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Size

Adult males are 2.34 m long on average, and weigh in excess of 300 kg. Sexual dimporphism is obvious from birth and females are much smaller: 2.03 m long and weigh 200 kg, rarely exceeding 300 kg. The colour is silvery; the body is scattered with dark, irregular marks. The head is darker than the rest of the body, and without marks.

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Lifestyle

In April through June, after the breeding season, they travel long distances to feed and eventually gather together again in separate moulting areas on the ice from June through August. After moulting, they disperse widely again to feed in the late summer and autumn before returning to the breeding areas in late winter.

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Breeding

There are four major breeding areas: the Gulf of St. Lawrence, the "Front" east of Newfoundland, Davis Strait (between Greenland and northern Canada) and the West Ice near Jan Mayan.

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Offspring

Pups are born about 1 m long and weighing about 24 kg on the ice from mid-March to early April with a well-developed blubber layer and having shed their pre-natal coat. They are born with a slate blue-grey coat (giving them the name "blueback"), with a pale cream color on the belly, which they will moult after about 14 months. Nursing of the pup lasts for an average of only 8 days, the shortest lactation period of any mammal, during which the pup doubles in size from about 24 kg to about 47 kg.

The female pup will mature between ages 3 and 6, whereas the male pup will mature between ages 5 and 7.

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