Elephant seal

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{{Taxobox | color = green | name = Sea Elephants | image = Elephant seal.jpg | image_width = 250px | regnum = Animalia | phylum = Chordata | classis = Mammalia | ordo = Carnivora | familia = Phocidae | genus = Mirounga | subdivision_ranks = Species | subdivision = M. leonina
M. angustirostris }}

There are two species of elephant seal. They are the sole members of the genus Mirounga of the family Phocidae or "true seals". The Northern Elephant Seal, Mirounga angustirostris, and the Southern Elephant Seal, M. leonina were both nearly to extinction by the end of the nineteenth century, but numbers have since recovered. The Northern elephant seal, somewhat smaller than its southern relative, ranges over the Pacific coast of the U.S. and Mexico, while the Southern Elephant Seal is found in the southern hemisphere on islands such as South Georgia, Macquarie Island and on the coasts of New Zealand and South Africa.

The elephant seals take their name from the great size of their bodies and the large proboscis of the adult males (bulls). That nose is used in producing extraordinarily loud roaring noises, especially during the mating season. The largest known bull elephant seal was 6.7 meters in length and weighed 3400 kilograms (about four tons). Therfore the Elephant seal is the largest member of the order Carnivora that ever lived.

Image:Elephant seals.jpg

Elephant seals spend an unusual amount of time in the ocean—up to 80% of their lives. They can hold their breath for over 80 minutes (longer than any other mammal). Furthermore, elephant seals are incredible divers as well, with an ability to dive to 1500 meters beneath the ocean's surface. The average depth of their dives is about 300 to 600 meters, as they search for their favorite foods, which are skates, rays, squid, octopuses, eels, and small sharks. While astounding swimmers, they are even more surprising on land, where they have a higher velocity than the average human when moving over sand dunes.

Elephant seals are shielded from cold by their blubber, much more than by fur. The skin on top of this blubber and its hair molts. It has to be re-grown by blood vessels reaching through the blubber. When this process is occurring, the seal is susceptible to the cold, and must rest and molt on land, in a safe place called a "hold-out." The type of molt which an elephant seal undergoes is a catastrophic molt. While this is taking place, the bulls actually cease fighting with one another.

Female elephant seals have an average life expectancy of about 20 years, and can give birth starting at the age of 3–4. Males reach maturity at five years, but generally don't achieve alpha status until the age of 8, with the prime breeding years being between ages 9 and 12. The average life expectancy of a male Elephant seal is 14 years.

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