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Unique Facts About Polar Bears

Polar bears are fascinating creatures with a variety of adaptations that have helped it survive and thrive in one of the harshest climates in the world, the Arctic Circle. The world's largest nonaquatic predator, polar bears have one-of-a-kind qualities that affect their appearance, behavior, hunting tactics and use of territory.

Appearance
- Polar bears are not white although they appear that way. Each shaft of hair is pigment free and the hollow core scatters and reflects light. This is similar to what happens with snow and ice. Contrary to popular belief, the hollow hairs do not conduct ultraviolet light to the animal's dark skin, according to Polar Bears International. Polar bears have black skin, with a thick layer of insulating fat underneath that can measure up to 4.5 inches.
Behavior
- Pregnant female polar bears will retreat to a den until her cubs are born.
  
  Polar bears are intelligent animals with IQs nearly that of apes. Research scientist Alison Ames has seen the animal smash blocks of ice to get to embedded fish and also stack plastic pipes for play activities. Polar bears do not hibernate in the winter like their brown and black bear cousins, although pregnant females will stay in a den until they give birth. Polar bears expend more than twice the energy of other mammals while walking. They prefer to walk slowly, but can run as fast as a horse over short distances. When food is scarce, polar bears enter a state of "walking hibernation" where they are able to reduce their metabolic rate to require less energy.
Hunting
- Polar bears are experts at stalking seals. They can smell a seal on ice from 20 miles away. They will crawl toward a seal basking on the ice and freeze if the seal raises its head. The bear will get to within 20 feet before it pounces. While they prefer seals, they will eat anything. Beluga whales that get trapped in small openings in ice packs can become easy polar bear meals. After eating, and sometimes during, the bear will wash frequently with water or snow to keep its coat in top condition.
Territory
- Polar bears often have huge territories where they hunt for prey.
  
  Polar bears mark their own distinct territories, and these areas are often huge. Scientists discovered a polar bear in Alaska had a territory that was 45 times the size of the Great Smoky Mountains National Park. This park is home to about 400 black bears. Most polar bears only travel within their territory, but scientists once tracked a female that walked more than 3,000 miles from Alaska to Greenland to Ellesmere Island in Canada and then back to Greenland. In 2006, a polar bear-grizzly hybrid was discovered in the Canadian Arctic. The bears can have overlapping habitats, but a wild mating is rare.

Animals & Science