The walrus (Odobenus rosmarus) is a large flipper marine animal with a discontinuous distribution about the North Pole in the Arctic Ocean and subartic seas of the Northern Hemisphere. The walrus is the only living species in the family Obenaide and genus Odobenus. This species is subdivided into three subspecies: the Atlantic walrus (O. r. rosmarus) which lives in the Atlantic Ocean, the Pacific walrus (O. r. divergens) which lives in the Pacific Ocean, and O. r. laptevi, which lives in the Laptev Sea of the Arctic Ocean.
Adult walrus are easily recognized by their prominent tusks, whiskers, and bulkiness. Adult males in the Pacific can weigh more than 2,000 kg (4,400 lb) and, among pinnipeds, are exceeded in size only by the two species of elephant seals. Walruses live mostly in shallow waters above the continental shelves, spending significant amounts of their lives on the sea ice looking for benthic bivalve mollusksto eat. Walruses are relatively long-lived, social animals, and they are considered to be a “keystone species” in the Arctic marine regions.