The polar bear's Latin name, Ursus maritimus, or "Sea Bear," refers to the animal's close association with the Arctic's chilly waters.

Alone among bears, the polar bear is considered a marine mammal.

Polar bears are often seen along open leads, where they hunt seals, as well as on the pack ice.

Polar bears spend as much time on the ice as they do on land.

Polar bears are champion swimmers. They have been known to swim more than 60 miles without a rest.

The polar bear's swimming limit is not known.

Polar bears have been clocked swimming as fast as six miles per hour.

A polar bear's forepaws are partially webbed to assist it in swimming. The massive size of the forepaws help as well. Each measures up to 12 inches in diameter.

Polar bears are skilled divers. They easily swim from one ice floe to the next.

When a polar bear emerges from the water, it shakes water from its fur like a dog.

A polar bear also wrings water from its fur by dragging itself across the ice.

Polar bears have excellent underwater vision. They can spot food up to 15 feet away.

The polar bear's fat layer, which is three to four inches thick, not only protects it from the cold, but adds to its bouyancy in the water.

Sources: San Diego Zoo/Wild Animal Park ZooNooz, February 1996; Polar Bears by Nikita Ovsyanikov (Voyageur Press, Stillwater, Minnesota, 1996).