Walrus (Odobenus rosmarus)- Part I (Introduction – distribution – description)- Video

This video was filmed during December 2014 in the Sea World, San Diego, California, USA.

Review: Abdel Rahman El Gamal (Founder of the video channel)

Introduction: The walrus, (Odobenus rosmarus) is the only living species in the Odobenidae family and Odobenus genus. Two subspecies of walrus are widely recognized: the Atlantic walrus, Odobenus rosmarus rosmarus  and the Pacific walrus, Odobenus rosmarus divergens. The common name, walrus, originated with the Danish word hvalros, meaning “sea horse” or “sea cow”.


Distribution and habitats:

Range: The walrus is circumpolar in its range but they are concentrated in geographically separated areas. The Pacific walrus is found in the Bering, Chukchi, and Laptev Sea, while the Atlantic walrus inhabits the coastal regions of northeastern Canada and Greenland.

Habitats: Most walruses live where the air temperature is about -15° to +5°C. Because of the limited diving abilities of walruses, they are generally found where the water is no more than 80 m deep. While walruses spend about two-thirds of their lives in the water, they haul out to rest and bear their young.

Migration: Walruses migrate primarily by swimming, but they may also ride ice floes. Some walruses migrate more than 3,000 km each year. In general, Pacific walrus adult females and young walruses are more migratory than adult males.


General: The walrus (Odobenus rosmarus) is a large marine mammal with flippers, a broad head, short muzzle, small eyes, tusks and whiskers. A walrus has a rounded, fusiform body. With wrinkled brown and pink hides, walruses are distinguished by their long white tusks, grizzly whiskers, flat flipper, and bodies full of blubber.

Size: The Walrus is the third largest pinniped species, after the two elephant seals. Male Pacific walruses normally weigh about 800 to 1,700 kg; Length typically ranges from 2.2 to 3.6m. In general, females weigh about two-thirds as much as males. Atlantic walruses weigh about 10–20% less than the Pacific walruses. The high body weight of walruses is due to the blubber stored underneath their skin. This blubber keeps the animals warm and the fat provides energy to the walrus. Newborn walruses are quite large, averaging 33 to 85 kg in weight and 1 to 1.4 m in length across both sexes.

Color: Young walruses are deep brown and grow paler and more cinnamon-colored as they age. However, they may appear almost white after a sustained period in very cold water because skin blood vessels constrict in cold water, while they are nearly pink in warm weather when tiny blood vessels in the skin dilate and circulation increases.

Flippers: The limbs in walruses are adapted as flippers. The flippers of walruses are hairless with thick and rough skin, providing traction on land and ice. For walking on land, walruses can rotate their rear flippers forward, while positioning its foreflippers at right angles to the body allowing them to walk on all fours. While during swimming, a walrus holds its foreflippers against its body or uses them for steering.

Tusks: The most prominent feature of the walrus is its long tusks. These are elongated canines which grow throughout their lives reaching about 1 m and weigh up to 5.4 kg. Tusks are present in both male and female and tend to be longer and thicker among males, which use them for fighting, establishing social dominance, and protecting their females during mating season. Tusks are also used to break breathing holes into ice from below and aid the walrus in getting out of water onto ice or rocky shores “tooth walking”.

Skin: A walrus’s skin is highly wrinkled, thick, tough and not particularly sensitive to touch. It may reach a thickness of 2 to 4 cm. In adult males, the skin is thickest around the neck and shoulders and may reach up to 15 cm thick, where it protects the animal against jabs by the tusks of other walruses. The blubber layer beneath is up to 15 cm thick.

Vibrissae: A walrus has about 400 to 700 vibrissae (whiskers) surrounding the tusks in 13 to 15 rows reaching 30 cm in length on its snout. Vibrissae are attached to muscles and are supplied with blood and nerves making them extremely sensitive tactile organs and so used as detection devices (e.g. locating food) especially in deep and murky waters when visibility is usually poor.

Sources: Defenders of Wildlife, National Geographic, Sea World, Wikipedia




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