Polar bear (Ursus maritimus) is the largest predator of the animal world. Body length of 1.6-3.3 m, weight of males 400-500 kg (sometimes up to 750), females - up to 380 kg Bear great swims and dives, swim in the open sea for tens of kilometers. Quickly moves on ice. Solitary lifestyle, but sometimes there are groups of 2-5 animals; some bear can be gathered about a major fall.
Polar bears hunt for fin primarily on ringed seal, sea hare, and the harp seal. Go to land, coastal zones, Islands and the mainland, hunt for walrus calves, also eat emissions sea, meat, fish, birds and their eggs, at least - rodents, berries, mosses and lichens. Pregnant females lie down in their dens, which suit on land from October to March-April. In broods usually 1-3, often 1-2 cub. To two years of age they are left with a bear. The maximum life expectancy of the polar bear 25-30 years, sometimes more.
In Russia, the polar bear constantly inhabits the space from Franz Josef Land and Novaya Zemlya to Chukotka. On the floating ice sometimes reaches of Kamchatka. Marked distant approaches to the mainland (up to 500 km along the river Yenisei. Southern border of the habitat coincides with the edge of the drifting ice. When it melts, and the destruction of the ice bears are moved to the Northern border of the Arctic basin. With the onset of stable ice formation animals begin their southward migration.