Range

Walrus are found in a circumpolar area around the Arctic and sub-Arctic areas. Resident populations can be found in Canada, Greenland, Russia, Svalbard and San Mayen along with the United States in Alaska.

Occasional vagrants have been recorded in Belgium, Denmark, Finland, France, Germany, Iceland, Ireland, Japan, Netherlands, Norway, Spain, Sweden, United Kingdom and in the states of Maine and Massachusetts in the United States.

Habitat

Walruses spend roughly two thirds of their life in the water tending to favor shallow areas. They will come to land on ice floes, pack ice and small rocky islands.

Reproduction

Females are in estrus and ready to breed from December through to March. Mating takes place in the water.

Males will compete for mating rights with the females. This involves them displaying and sparring at the other males to obtain favored positions at the breeding site which provides them access to the females.

A single calf is born after the 15 to 16 month gestation period which will include a period of delayed implantation between 4 and 5 months long.

The calf will suckle for up to 6 months before being weaned at 18 months old.

If a pup is orphaned another female within the group may adopt them.

Females mature earlier at 5 to 6 years for female sexual maturity compared to between 8 and 10 years for males. Females tend to give birth once every two years.

Behavior

Walruses will embark on foraging trips which last from a few hours to several days. During these expeditions they can dive under water for up to 25 minutes reaching depths of as much as 100m (330ft) deep.

These animals are social and will live in large groups on land. At sea they divide in to smaller groups of less than 10. A group of walruses is called a herd.

Walruses can survive in their cold environment as a result of the blubber which keeps them warm and their ability to slow their heart rate.

Predators and Threats

Their large size leaves them with few natural predators though polar bears and killer whales will threaten them.

Humans have impacted the population of the walrus through hunting for their meat, hide, ivory and bones. Another threat is increased human disturbance in their range from oil and gas exploration.

They receive a number of protections under law which have helped to stabilize their population.

Global warming has caused the sea ice on which they haul out to melt and this can cause overcrowding in groups of walrus. Young may be trampled to death here and if there is a stampede in the group back to the water hundreds of them may be killed.

Quick facts

Two subspecies of the walrus are recognized. These are the Pacific and Atlantic walrus. The Pacific walrus is considered the more common subspecies.

Their scientific name (Odobenus rosmarus) comes from Latin meaning "tooth-walking sea-horse."

Walrus are the second largest pinniped species after the elephant seal.