by Sam Cliby

Created on: April 13, 2008   Last Updated: April 15, 2008

Polar bear

The polar bear is well equipped for life in the icy Arctic Circle. It is immensely strong and active, capable of covering short distances very rapidly, and diving off ice floes into the sea. It travels thousands of miles each year in search of food, a covering of hair on the soles of its feet providing extra stability on the slippery ground.

Food and hunting

Polar bears mainly feed on seals, and usually eat the fat and skin first, saving the meat until last. They catch seals by waiting at a breathing hole or stalking them on the ice. As soon as the polar bear has caught a seal, they instantly kill it by a crushing blow to the skull with its paw. In late summer and early autumn the polar bear will patrol coastal areas looking for whale and walrus carcasses. As there is more open land at this time of year, it also feeds on land mammals such as lemmings, and arctic foxes, as well as eider ducks and their eggs and chicks. The polar bear will also eat berries, mosses, toad stools, lichens, sedges, grasses, seaweeds and mountain sorrel.

Habits

The polar bear is found all around the polar region, but spends most of its time along the southern edge of the arctic pack ice. A combination of pack ice, open water and land is ideal habitat. Mostly a solitary animal, the polar bear is active for most of the year but spends a large part of winter in a den beneath the snow. It's an excellent swimmer, jumping into the water, like a dog, or sliding in backwards, cruising at about 10 km/h, using only its front legs to propel it. With its eyes open, and its nostrils closed, it dives beneath the surface, staying submerged for up to 2 minutes at a time. When it emerges from the water, it shakes to remove from its coat before it freezes.

Breeding

Spring is the polar bears mating season, with most activity in April. The male moves about during this period, seeking females without cubs. Most females breed every third year, after separating from there young. In October and November, both male and female polar bears dig out a den in the snow. The den is usually located on the south facing slope of a hill, where northerly winds pile up the snow. Although any bear may dig a den, it is mainly the pregnant females that shelter in a den for extended periods. Polar bears are born in November or December and weigh only 600-700g. The young are blind, hairless and about the size of a rat. They first leave the den in March or April, when they weigh about 8-12kg, but will remain with their mother into the third spring of their life.

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