Southern Elephant Seal

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Southern Elephant Seal
Conservation status
Least concern (LR/lc)
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Suborder: Pinnipedia Family: Phocidae Genus: Mirounga Species: M. leonina
Binomial name
Mirounga leonina Linnaeus, 1758

The Southern Elephant Seal (Mirounga leonina) is one of two species of elephant seal (the other is the Northern Elephant Seal). It is the largest member of not only the family Phocidae or "true seals", but also of the order Carnivora.

The elephant seals get their name from their great size and the fact that the adult males have a large proboscis, which is used in making extraordinarily loud roaring noises, especially during the mating season. There is a great sexual dimorphism in size, with the males very much bigger than the females (they are called bulls and cows), and correspondingly there is a highly polygynous mating system, with a successful male able to impregnate up to 40 females in one season. While the females average about 680 kg (1,500 lb) and 3 m (10 feet) long, the bulls average around 2045 kg (4,500 lb) and 4.5 m (15 feet) long. The record bull, shot in Possession Bay, South Georgia in 1913, was 5000 kg (11,000 lb) and 6.9 m (22.5 feet) long.

Southern Elephant Seals are found throughout the Sub-Antarctic regions, coming ashore to breed in the summer but wintering at sea. They used to live in large numbers around Tasmania, but were wiped out by the sealing industry and are now only seen there a few times a year. They are occasionally seen off the coasts of New Zealand and South Africa. They breed on the subantarctic islands, with the population at South Georgia being the largest (it includes about half of the entire species population). Other important populations are at Macquarie Island (over 80,000 individuals), Península Valdés, Heard Island and the Kerguelen Islands.

After their near extinction due to hunting in the 19th century, total population is about 600,000, but all the populations seem to be declining at present. The reasons for this are unclear, but it may simply be that once protection from hunting was established, the species recovered so fast that it overshot its equilibrium numbers. Most of their most important breeding sites are now protected by international treaty, as UNESCO World Heritage Sites or by national legislation.

Elephant seals feed in deep water, and can dive to great depths, up to 1700 metres. Dives lasting up to two hours have been recorded. They feed on cephalopods such as squid and cuttlefish, and large fish including sharks. When at sea, they spend a high proportion of their time underwater, and they only need to spend a few minutes on the surface between dives.

[edit] References

• Seal Specialist Group (1996). Mirounga leonina. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 09 May 2006.

• Mirounga leonina (TSN 180671). Integrated Taxonomic Information System. Accessed on 24 January 2006.

[edit] External links

• ARKive - images and movies of the southern elephant seal (Mirounga leonina)
• http://www.pinnipeds.org/species/selephnt.htm
• Elephant Seal Research Group - http://www.eleseal.it