Crabeater Seal

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Crabeater Seal
Conservation status
Least concern (LR/lc)
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 fifteen million, 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 200 cm (7 feet) 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.

[edit] References

1. ^ Bryson, Bill. A Short History of Nearly Everything. 285
2. ^ BONNER B 1995 Birds and Mammals - Antarctic Seals. in Antarctica Pergamon Press 202 - 222

[edit] Further reading

• Seal Specialist Group (1996). Lobodon carcinophagus. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.