General facts about all bears:

  • Bears are mammals.

  • Bears are found in many habitats in different countries.

  • Bears all have a large body with strong legs and a short tail. They have a snout rather like a dog's snout. They have thick fur. Their paws have five claws that do not pull back like a cat's claws do.

  • Bears generally live alone, except when a mother is raising cubs.

  • There are eight different kinds of bear.

What do polar bears look like?

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Together with their close relatives, the kodiak brown bear, the polar bear is the largest of all bears, and the largest land predator. Males weigh about 500-600 kilos and are about 3 metres from nose to tail, and about 1 metre tall when standing on all four feet.  Females are about 300 kilos and a bit smaller in size. Though it spends time on land and ice, the polar bear is often thought of as a marine mammal because it spends so much time in the sea and swims so well.

©Getty Images

©Getty Images

The polar bear has a thick body with a very short tail about 10 cm long. They have a thick layer of body fat to help keep them warm. The legs and neck muscles are strong. Their necks are quite long, so they can keep their heads above water while swimming. The soles of their very large feet (about 30 cm across) are covered with stiff, thick fur to give them grip when they walk on ice. The polar bear can reach a speed of about 32 kph when moving on flat ice.  

Polar bears have three eyelids: the third eyelid helps protect their eyes in such a severe climate. Their excellent sense of smell enables them to locate prey many miles away.

Their fur looks white or creamy, but actually each individual hair is transparent and hollow. This means that the hairs act like greenhouses: they turn the sunlight into heat, which is absorbed by the bear's skin, which is black. Black is a good colour for absorbing and keeping warmth. 

Habitat and Distribution (where they are found)

Polar bears are are found in the top part of the northern hemisphere, in and around the Arctic Ocean which includes parts of Russia, Norway, Greenland, Canada and the U.S.A. The size of its range varies with the pack ice of the Arctic.

Pack ice forms in winter when the Arctic Ocean freezes and there is a crust of floating ice which moves with ocean currents. Pack ice can be very flat because the ocean is flat but there are rough patches where sheets of ice rub against each other.  Where it is locked to the shore, pack ice is called fast ice.  Pack ice is not always continuous - cracks (called leads) open up suddenly then re-freeze, so new ice is added all through the long winter.

Polar bears swim far out in the open sea ©Getty Images

Polar bears swim far out in the open sea ©Getty Images

What are their behaviours?

Polar bears are excellent swimmers, able to swim more than 95 km without a rest. They can swim underwater for up to 2 minutes, and can dive down about 5 metres. They have webbing between their toes to help them paddle. They flatten their short, furry ears and close their nostrils when swimming.

Like other kinds of bear, polar bears are solitary, except for females with young. Males take no part in caring for young cubs, and in fact may injure or kill them. 

Polar bears eat plenty of food in autumn so their bodies have extra fat to keep them alive while they hibernate through winter. They wait motionless near holes in the ice where seals come up to breathe.

Mother with cubs. ©Getty Images

Mother with cubs. ©Getty Images

Diet

Polar bears eat meat. They have 34 - 42 very sharp teeth. They catch seals and sometimes walrus pups, as well as birds, beluga whales, musk oxen and reindeer.

They hunt in places where there are cracks in the ice that seals may use to come up for air. When food is scarce, they eat any dead animals they find along the shore, as well as birds eggs, small animals, shellfish and any other edible things they can find. They will sometimes eat berries or seaweed, and even garbage left by humans, when other food is scarce.

Life Cycle

Polar bears mate between March and July. In November females get ready to give birth, and go into dens to hibernate, which is a kind of sleep during which their heart rate and temperature drop. They make oval dens 3 metres long, with a tunnel to the surface.  Cubs are born in the dens in December or January while their mother is hibernating. The number of cubs born is usually 2.

The tiny cubs are blind, hairless and toothless. They drink milk from their sleeping mother, and develop fast because polar bear milk is very high in fat.  By the time their mother leaves the den in March or April, the cubs are big enough to follow her. By this time they weigh about 10-15 kilos. They stay with their mother for about two to three years, learning skills they need to survive in this harsh habitat.

Global warming is affecting the habitat and hunting ©Getty Images

Global warming is affecting the habitat and hunting ©Getty Images

Conservation Status and Threats

Polar bears are classified as Vulnerable. The destruction of its habitat on the Arctic ice through global warming threatens the bear's survival. The pack ice is a large platform from which polar bears hunt for their main food, ringed seals. The ice is thinning, and is in place for a shorter time so that polar bears have a shorter hunting time.  As the ice melts, the bears have to come ashore earlier and before they have eaten enough to keep them going through their hibernation.  Pollution is also posing a threat to these bears. It is thought that there are about 20,000 to 25,000 polar bears in total left in the wild.

Read more about polar bears:

Watch a video about polar bears and kodiak bears in the Arctic