Polar bears are diurnal (active during the day) and are more active during the first third of the day than during the last third. They are solitary, except during the breeding season and when females are with their cubs. Polar bears can run 25 mph for short distances, swim for miles at a time across open water, and stay underwater for about two minutes. They can launch themselves out of the water and land on all four feet on the ice. Their short, curved, sharp claws grip the ice, enabling them to cling to ice floes or to climb towering pressure ridges. Males and nonpregnant females remain active all winter; pregnant females go into dens.
Status in the Wild
Polar bears are sexually dimorphic in size. Males are larger than females are. Polar bears are covered in a thick, dense coat of hair. Each hair is a hollow tube that lacks pigment. When the sunlight bounces off the hair shaft, it appears white in color. Wild bears may look yellowish in the summer due to the oxidation of seal oil on their coat. Their fur does not repel water; polar bears can become hypothermic (their body temperature is too low) if they are immersed too long. They have 4 to 5 inches of blubber that insulates their body. They have a small, round head and a long neck. Their feet are flat, large, and oarlike. They have a membrane between their toes that is up to half the length of the toes. These are adaptations for swimming. Fur covers the soles of the paws, except for the foot pads. This provides traction and warmth against the ice. Black skin under the fur absorbs the warming ultraviolet rays of the sun. They have a very long neck and small ears. Their nose, foot pads, and the skin under their fur is black.
Adopt a Polar Bear
Polar bears' habitat is threatened not only by exploration for gas and oil but also through sport and native hunting. Alaskan natives have exclusive rights to hunt polar bears without limits or a closed season. They are not required to report the number of bears they kill.