A hungry polar bear comes out of its den into the cold wind and blowing snow. It runs on the thick ice until it reaches the water. Splash! The bear dives into the icy water for a long, cold swim. It swims with only its nose showing.

How do polar bears swim so comfortably in icy water? How do they run so easily on frozen land? The Arctic is the area of the earth that surrounds the North Pole. Part of the Arctic is land. Part of it is water. Fore more than half of the year, much of the Arctic is frozen.

Animals who live in this cold, harsh place need ways to keep warm and safe. Polar bears have thick fur that keeps them warm, even during the cold, Arctic winter. Polar bears get most of their food from the water. They have sharp claws and teeth for catching seals, walruses, seabirds and fish. They hunts seals at holes in the ice where the seals come up for air. Polar bears must go from place to place to follow their prey. Sometimes they travel many miles by swimming in the water or riding on a big chunk of ice.

If polar bears cannot find food in the water, they hunt on land. Polar bears have thick pads and fur on their feet to help them walk or run on slippery ice and snow. The land animals they hunt include large animals, such as reindeer and musk oxen, and small animals such as lemmings. Polar bears can smell animals from up to ten miles away. They can even smell animals homes that are buried under snow and ice.

Polar bears are huge animals. Many polar bears grow to a length of nine feet. They can weigh up to 1600 pounds. They are so strong that they can kill a seal with one swipe of a paw. It is very dangerous for a person to get close to a polar bear. One way is by watching them through a powerful telescope or binoculars. From the top of a high cliff, scientists will often watch a mother polar bear teach her cubs to hunt seals at an ice hole. When polar bears are walking on the ice, scientists can use an underwater microphone to bring the sound of the bears closer.