Polar bears Arctic

Polar bears live along shores and on sea ice in the icy cold Arctic. When sea ice forms over the ocean in cold weather, many polar bears, except pregnant females, head out onto the ice to hunt seals. Polar bears have been spotted on sea ice hundreds of miles from shore. When the warm weather causes the sea ice to melt, polar bears move back toward shore. Polar bears primarily eat seals. Polar bears often rest silently at a seal's breathing hole in the ice, waiting for a seal in the water to surface. Once the

seal comes up, the bear will spring and sink its jagged teeth into the seal's head.

Sometimes the polar bear stalks its prey. It may see a seal lying near its breathing hole and slowly move toward it, then charge it, biting its head or grabbing it with its massive claws. A polar bear may also hunt by swimming beneath the ice.In fall pregnant polar bears make dens in earth and snowbanks, where they'll stay through the winter and give birth to one to three cubs. In spring the mother emerges from her den followed by her cubs. Generally, she will nurse them for two and a half years. During that time she will protect them and teach them how to hunt.

The U.S., Canada, Denmark, Norway, and the Soviet Union signed an agreement in 1973 to protect polar bears. 

FAST FACTS
Paw pads with rough surfaces help prevent polar bears from slipping up on the ice.

Polar bears swim using their large front paws to propel themselves through the water and their back legs to steer.

Only humans prey on polar bears.The scientific name for polar bear is Ursus maritimus, which means "sea bear."

Adult males generally weigh between 720 and 1,700 pounds (363 and 771 kilograms). Adult females often weigh between 500 and 600 pounds (227 and 272 kilograms). Males can grow to ten feet (three meters) in length—the height of a one-story building.Polar bears are the largest predators on land, and they are the largest of all bears.

Polar bears have fur and skin that allow them to absorb sunlight for warmth. Their blubber, or fat, insulates them in cold water.

Polar bears have been known to swim 100 miles (161 kilometers) at a stretch.