Crabeater Seal

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iCrabeater Seal

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Family:	Phocidae
Genus:	Lobodon
Species:	L. carcinophagus

Binomial name

Lobodon carcinophagus
Hombron & Jacquinot, 1842

The Crabeater Seal, Lobodon carcinophagus, is one of the most remarkable, though least known, of the mammals of the world. At a population of 8 to 50 million (LAWS 1973), it is perhaps the "second most numerous large species of mammals on Earth, after humans."^[1] More than one in every two seals in the world is a Crabeater Seal and the population biomass of Crabeaters is about four times that of all other pinnipeds put together ^[2].

Schematic of the skull, showing the unusual shape of the teeth.

Despite its name, its diet does not include crabs. Instead, a crabeater seal's unusual multilobed teeth enable this species to sieve krill from the water. Its dentition looks like a perfect strainer, but how it operates in detail is still unknown. The food of Crabeater Seals consists 98 % of Antarctic krill, Euphausia superba. The seals consume over 63 million tonnes of krill each year. They live and reproduce in the pack ice zone around Antarctica.

Females grow up to 360 m (142 in) in length and 500 lb (230 kg) in weight. Crabeater Seals colonized Antarctica during the late Miocene or early Pliocene (15 - 25 million years ago), at a time when the region was much warmer than today. The evolution into this strange, successful and abundant animal can be taken as a token of the bounty and continuity of krill.

The seals background colour is mainly silvery grey when newly moulted, or golden to creamy white when the coat has faded. Older animals become prograssively paler, even when freshly moulted, and may appear almost white. In younger animals, there are net-like , chocolate-brown markings and felcks on the shoulders, sides and flanks, shading into the predominantly dark hind and fore flippers and head.