page_title: Polar bear
section_title: Hunting and diet
hierarchical_section_title: Polar bear / Life history and behaviour / Hunting and diet
caption_attribution_description: Deutsch: Ein Eisbär (Ursus maritimus) im dichten Treibeis nördlich von Spitzbergen hat eine Bartrobbe erlegt und beginnt, sie auszuweiden. English: After successfully hunting a Bearded seal (Erignathus barbatus), a Polar bear (Ursus maritimus) starts feeding on his prey. He enjoys his meal on an ice floe north of Svalbard, Norway.
context_page_description: The polar bear is a hypercarnivorous bear whose native range lies largely within the Arctic Circle, encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the largest extant bear species, as well as the largest extant predatory carnivore. A boar weighs around 350–700 kg, while a sow is about half that size. Although it is the sister species of the brown bear, it has evolved to occupy a narrower ecological niche, with many body characteristics adapted for cold temperatures, for moving across snow, ice and open water, and for hunting seals, which make up most of its diet. Although most polar bears are born on land, they spend most of their time on the sea ice. Their scientific name means "maritime bear" and derives from this fact. Polar bears hunt their preferred food of seals from the edge of sea ice, often living off fat reserves when no sea ice is present. Because of their dependence on the sea ice, polar bears are classified as marine mammals.
  Because of expected habitat loss caused by climate change, the polar bear is classified as a vulnerable species.
context_section_description: The polar bear is the most carnivorous member of the bear family, and throughout most of its range, its diet primarily consists of ringed (Pusa hispida) and bearded seals (Erignathus barbatus). The Arctic is home to millions of seals, which become prey when they surface in holes in the ice in order to breathe, or when they haul out on the ice to rest. Polar bears hunt primarily at the interface between ice, water, and air; they only rarely catch seals on land or in open water.
  The polar bear's most common hunting method is called still-hunting: the bear uses its excellent sense of smell to locate a seal breathing hole, and crouches nearby in silence for a seal to appear. The bear may lie in wait for several hours. When the seal exhales, the bear smells its breath, reaches into the hole with a forepaw, and drags it out onto the ice. The polar bear kills the seal by biting its head to crush its skull. The polar bear also hunts by stalking seals resting on the ice: upon spotting a seal, it walks to within 90 m (100 yd), and then crouches. If the seal does not notice, the bear creeps to within 9 to 12 m (30 to 40 ft) of the seal and then suddenly rushes forth to attack. A third hunting method is to raid the birth lairs that female seals create in the snow.
  A widespread legend tells that polar bears cover their black noses with their paws when hunting. This behaviour, if it happens, is rare – although the story exists in the oral history of northern peoples and in accounts by early Arctic explorers, there is no record of an eyewitness account of the behaviour in recent decades.
  Mature bears tend to eat only the calorie-rich skin and blubber of the seal, which are highly digestible, whereas younger bears consume the protein-rich red meat. Studies have also photographed polar bears scaling near-vertical cliffs, to eat birds' chicks and eggs. For subadult bears, which are independent of their mother but have not yet gained enough experience and body size to successfully hunt seals, scavenging the carcasses from other bears' kills is an important source of nutrition. Subadults may also be forced to accept a half-eaten carcass if they kill a seal but cannot defend it from larger polar bears. After feeding, polar bears wash themselves with water or snow.
  Although polar bears are extraordinarily powerful, its primary prey species, the ringed seal, is much smaller than itself, and many of the seals hunted are pups rather than adults. Ringed seals are born weighing 5.4 kg (12 lb) and grown to an estimated average weight of only 60 kg (130 lb). They also in places prey heavily upon the harp seal (Pagophilus groenlandicus) or the harbour seal. The bearded seal, on the other hand, can be nearly the same size as the bear itself, averaging 270 kg (600 lb). Adult male bearded seals, at 350 to 500 kg (770 to 1,100 lb) are too large for a female bear to overtake, and so are potential prey only for mature male bears. Large males also occasionally attempt to hunt and kill even larger prey items. It can kill an adult walrus (Odobenus rosmarus), although this is rarely attempted. At up to 2,000 kg (4,400 lb) and a typical adult mass range of 600 to 1,500 kg (1,300 to 3,300 lb), a walrus can be more than twice the bear's weight, has extremely thick skin and has up to 1-metre (3 ft)-long ivory tusks that can be used as formidable weapons. A polar bear may charge a group of walruses, with the goal of separating a young, infirm, or injured walrus from the pod. They will even attack adult walruses when their diving holes have frozen over or intercept them before they can get back to the diving hole in the ice. Yet, polar bears will very seldom attack full-grown adult walruses, with the largest male walrus probably invulnerable unless otherwise injured or incapacitated. Since an attack on a walrus tends to be an extremely protracted and exhausting venture, bears have been known to back down from the attack after making the initial injury to the walrus. Polar bears have also been seen to prey on beluga whales (Delphinapterus leucas) and narwhals (Monodo
caption: Bear feeding on a bearded seal
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