Pacific walrus spend all or the majority of their time in water, and thus are specially adapted to this way of life. Their thick layers of fat help to keep them warm in frigid waters. Since they are mammals, they must always come up to the surface to breathe, although they can often hold their breath for surprising lengths of time.

The scientific name of the walrus means "tooth-walker." The tusks, which are enlarged teeth, are used to help the animal move around on land or ice. In addition to their distinctive tusks, walrus are also impressive on account of their size. Large males can weigh more than 3300 pounds and be more than 10 feet long. These bulky animals, which move so awkwardly on land, are well suited for their marine existence.

Walrus do not have external ear flaps. The head of the walrus is small in relation to the body, with small eyes and a muzzle covered with vibrissae. Adult males have bumpy nodules covering their necks and shoulders. Walrus use their vibrissae to feel along the ocean floor and locate clams, which they then suck out of their shells. They may also eat softshell crabs, slow-moving fish, snails, worms, shrimp, or even other marine mammals such as seals.

Coloring

The color of walrus varies. When walrus are in cold water, they may appear pale brown, grey, or even yellowish. On land, when walrus are warm, they are pinkish to darker brown. This color change is a result of their temperature regulation mechanism; when cold, walrus restrict blood flow to the outer layers of their skin and blubber to conserve heat. When they are warm, blood vessels dilate and allow blood to flow to the surface, bringing color and allowing excess heat to radiate from the animal.

Walrus as Prey

Walrus are an important source of food for local residents, providing meat and blubber. Occasionally, walrus may fall prey to polar bears and killer whales, but their tusks can be formidable weapons for defense.

Important Ice

Walrus are traditionally associated with pack ice, and as ice cover retreats northward during the summer months, most of the animals follow it. A sizable group of males, however, remains behind in the Bristol Bay area during the summer months, hauling out in several spots around the region. Togiak Refuge has an ongoing marine mammal monitoring program to document their distribution.

Breeding

Walrus mating takes place underwater, and pups are born 15 months later, in mid-April through mid-June. Mothers nurse the young for up to two and a half years. Females in their prime give birth on alternate years, becoming pregnant while still suckling an older pup.

Resources:

Reeves, Randall R. et al. 1992. The Sierra Club handbook of seals and sirenians. Sierra Club Books. San Francisco California.