Polar bears prefer eating blubber to meat.
Polar bears live mainly on the Arctic pack ice, moving south in winter as the ice extends and north in summer when it melts back. Their white fur camouflages them on the ice, helping them stalk prey without being seen. Under the fur, their black skin absorbs heat. Hollow hairs and a thick layer of blubber (fat) also keep out the cold.
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Each autumn, polar bears arrive at the town of Churchill, on the edge of Hudson Bay. They have spent summer in the forest, but hunt on the ice in winter. If the ice is late forming, they hang around the dump. They sometimes enter the town and make a nuisance of themselves.
Q: Can polar bears swim?
A: Yes! Despite their ‘doggy paddle’ swimming style, polar bears are fantastic swimmers. They are true marine mammals and can swim many kilometers from one ice floe to another. To help them to do this, their coat is water repellent and their feet are partly webbed.
A female polar bear gives birth, usually to twins, in a snow den in winter. After eating little all winter, she is hungry and must hunt seals to put on weight and produce milk for her cubs. But she must be careful. If a male bear spots them, he will attack the mother and kill the cubs.
When stalking seals on the ice, a polar bear was once seen to cover up its black nose with its furry paw so that it could not be seen!
Hooded seal mothers feed their babies milk for just one week!
On the ice
Seals are mammals. They get oxygen from the air, so they must return to the surface regularly to breathe. In the spring, they leave the water to pup (give birth) in snow or ice dens or on top of the ice itself. When out of the water, Arctic seals are in danger of being eaten by the region’s number one killer-the polar bear.
How many male hooded seals can you count?
Hooded seals live in the Arctic. At breeding time the males display to females and to one another. They do this by blowing out the lining of one nostril into an outsize red balloon or by inflating their black nose hood.
Seals maintain open holes in the ice so that they can breathe regularly. A polar bear may sit for hours at a breathing hole, waiting for a seal to surface. As soon as it does, one swipe from the bear’s powerful forepaw will haul the seal out onto the ice.
Ringed seal pups are reared in snow dens. Each den has an escape hath to the sea. Polar bears can smell the seals and break in the roof, so a mother often has several dens. She leaves some empty to confuse the bears.
Walrus males use their tusks for displaying to females and for hauling themselves out onto ice floes.
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In summer, hundreds of male walrus haul themselves out onto Round Island, Alaska, to sun themselves. When they leave the water they are pale grey. This is because the blood withdraws from their skin in cold water so that they don’t lose heat. As they warm up on land, the blood reaches their skin and they turn bright pink.
The leopard seal is one of the Antarctic’s fiercest marine predators. It stakes out penguin colonies and grabs the birds when they enter the water. It throws its victim into the air and skins it alive before swallowing the flesh.
The Weddell seal patrols an under-ice territory, which it defends by making a singing noise. It has a breathing hole that it must keep clear, using its teeth to chisel away regularly at the ice. Eventually, its teeth wear down or rot and the seal dies because it cannot keep its ice hole open.
Seals appeared in the northern hemisphere about 30 million years ago. During a cold period in the Earth’s history, some headed south. Today, the crabeater seal population in the Antarctic is the largest in the world-possibly more than 15 million seals-making it the most numerous large mammal on the planet after humans.