The Polar Bear “Melting Glacier” The polar bear (Ursus maritimus) 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 land carnivore. A boar (adult male) weighs around 770–1,540 lb, while a sow (adult female) 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. Most polar bears are born on land but 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. By 2040, scientists predict that only a fringe of ice will remain in Northeast Canada and Northern Greenland due to global warming. This "Last Ice Area" is likely to become important for polar bears and other life that depends on ice. A projection of sea ice in the archipelago, supported by WWF, shows that much of the region is facing significant ice loss in the coming decades - with potentially serious consequences for polar bears. Global polar bear numbers are projected to decline by 30% by 2050.
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