Polar bears live in all parts of the Arctic, but most live in Canada. Most of where the polar bear lives is where there is lots f snow and very cold. They have ways of combating the cold like their fur and fat layers but most important is a form of hibernation. In the autumn many polar bears dig out dens in the shelter of rocks or cliffs.
The polar bear sleep for several months, resting and sleeping in a comfortable retreat, well insulated by a blanket of snow. During this period, the bear lives off its stored body fat but, unlike smaller mammals that hibernate, the bear's body temperature, heart rate, and breathing rate slow down only very slightly and the animal can quickly arouse itself to full activity. The environment affects the life of the polar bear a lot because if it was not so hot, they would not have to dig summer dens and need so much fat.
Food and Eating
In the course of the polar bear's hunting, a polar bear may travel up to 25 miles in a day before finding food. Polar bears have a very acute sense of smell. They can smell carrion such as a dead whale from 20 miles away and can sniff out seal dens that are covered with snow. They are scavengers, feeding on the carcasses of walrus, beluga, bowhead whales and narwhals when they wash up on land. Normally they eat only seal's blubber and intestines. When a polar bear gets within l00 feet or so of a seal, the bear charges across the ice and seizes its victim, killing it before it can
escape. A seal may have several different breathing holes and so a bear has to wait patiently for one to pop up to breathe, then he pounces on the seal and quickly drags it onto the ice to kill it.
Life Cycle - Mating and Reproduction
The male polar bear looks for a mate in spring. Mating takes place in April and May. Male and female polar bears might stay together for just a few hours while mating takes place. Females can continue to breed until 20 years of age.
At the start of the Arctic winter when the sun appears above the horizon, for a short period each day, the female polar bear starts to look for a place where she can give birth to her cubs. She seeks out a place sheltered by a valley, slope or cliff where winds have already piled the snow into drifts. Using her big and strong feet and claws she digs a tunnel into a sloping edge of snow. At the end of it she shapes a comfortable chamber packing and stamping down the snow., as she turns around until it has walls, a roof, and a floor. Most dens are oval shape, six to nine feet long and about six feet in height and width.
Females give birth to one to three cubs, usually two. Cubs weigh only about 25 ounces and can fit into the palm of your hand. The young leave the den with their mother at about four months but remain with her for another year or so. Polar bears are fully grown at around five or six years of age. A polar bear's life span is around
Appearance
An adult male polar bear may measure more than nine feet in length and weigh over 2000 pounds. The largest polar bear ever seen was more than eleven feet tall. They are twice the size of a tiger or lion.
The polar bear is the largest omnivore living on the Arctic land. An omnivore is an animal that eats meat as well as fruit and plants. The polar bear has a layer of fat that can be as many as four inches thick. The polar bear can survive even when the temperature drops to minus 70 degrees because its fat keeps its body heat trapped inside. Scientists have recently discovered that the hairs on a polar bear are hollow and can channel ultraviolet light from the sun down to the bear's black skin, which absorbs it. This means that the bear's body is somewhat like a greenhouse, trapping solar energy and then storing it in the form of heat.
The only visible dark places on a polar bear is their eyes, nose and lips, the rest is all white fur. The black nose of a polar bear on the white snow can be seen from six miles away in a clear day through binoculars. It has been said that when stalking seals a polar bear will cover its nose with a paw to escape detection.
Polar bears are strong swimmers and can swim up to six miles per hour. Polar bears have been seen swimming 50 miles from ice or land. "They can swim, run, and leap better than any Olympic gold medalist" (Melissa L. Kim). Who do you know that has leaped 15 feet, sprinted 25 miles per hour and swim six miles per hour?
Even though polar bears live in the Arctic, they sometimes need to cool down. In the summer, temperatures on land can reach up to 70 degrees. Bears on land dig out shallow "summer dens" in order to escape the heat and insects. Younger male polar bears sometimes indulge in "play" fighting. Every autumn polar bears visit Churchill's trash dump while waiting for Hudson Bay to freeze then they will walk back to the permanent ice.
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