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General Characteristics

The walrus belongs to the Odobenid family (Odobenidae), which includes one species with two subspecies, the Atlantic walrus (O. rosmarus rosmarus), the Pacific walrus (O. rosmarus divergens) and maybe a third one off the North coast of Asia, particularly in the Laptev Sea (O. rosmarus laptevi). The three subspecies are geographically isolated, and present slight differences in cranial morphology and tusk characteristics (Reeves et al. 1992).

CLydersen walrus group 128 2824

Photo: K. Kovacs and C. Lydersen / Norwegian Polar Institute

Size

Male Atlantic walrus reach weights of 1200 to 1500 kg and lengths of close to 3 m. Females are smaller than males, weighing up to around 600 - 700 kg and reaching lengths of 2.5 m (Born et al. 1995).

Productivity

One calf every 2-3 years from 5-12 years of age. 

Lifespan

Up to 40 years.

Migration

Throughout their range walrus inhabit cold Arctic and subarctic waters, living amongst pack ice, in leads and polynyas in winter occupying coastal areas with access to shallow water during the spring, summer and fall.

Feeding

Mainly bivalve mollusks (clams) and other benthic (sea bottom) invertebrates. Some walrus, particularly large males, hunt and kill seals, birds and even narwhals and belugas.

Names

Latin: Odobenus rosmarus rosmarus

Faroese: Roysningur
Greenlandic: Aaveq
Icelandic: Rostungur
Norwegian: Hvalross

English: Atlantic walrus

The origin of the name "walrus" is uncertain, but it may be derived from the Old Norse word hrossval, meaning "horse-whale".


General

Walrus are a cinnamon-brown colour overall. After a long period in cold water, they may appear almost white, as blood vessels to the skin constrict to conserve body heat. A walrus' skin is very tough, and may be from 2 to 4 cm thick. Both male and female walrus have long ivory tusks, which are modified upper canine teeth. Male walrus tusks tend to be longer and thicker than those of females. Another distinguishing feature of walrus is the presence of many stout vibrissae or whiskers on the snout. The vibrissae are attached to muscles and are supplied with blood and nerves, and are used mainly to feel for food in bottom sediments.

KKovack walrus kit walrus 01

Photo: K. Kovacs and C. Lydersen / Norwegian Polar Institute

RStewart MG 1219 curious in water

 

A group of walruses in the water. Note the lighter coloured animal in the front, who has likely been in the water longer than the other animals (see above). Photo: R.E.A. Stewart

 Listen to walrus here and here!
Watch a video of walrus mother and calf. 



References