The Polar Bear Essay Research Paper INTRODUCTIONUrsus — страница 2

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see its familiar black nose. Once the polar bear has caught its seal, it will usually eat just the skin and blubber. The bear will eat very quickly, eating large chunks and not even chewing for about half an hour. It does this so no other animals will come and steal the food from it while it is eating. After it is done, the bear will climb in the water and wash its face and paws. It may do this for up to 15 minutes. Polar bears, like any other animal, need a good supply of fresh water in their diet. Since there is mostly ocean in the Arctic, the polar bear has to get its water elsewhere. It looks for old ice. It knows that in these areas of old ice, the salt has settled down through the ice blocks and left behind puddles of fresh water. RESPONSE Living in such harsh climates as

the Arctic, a polar bear has to have great senses and other adaptations in order to survive. It has one of the best senses of smell of all animals. It can smell a kill from several miles off and as previously noted, seal breath from a great distance. They first pick up a scent in the driving air, then follow it like a single beam back to its source. The beam is probably rather narrow, and to keep it in focus, the great bears occasionally stand upright and sniff, moving their head from side to side. It also has excellent vision. It can tell what is going on around it just by a quick glance and often will see its prey long before its prey sees it. The polar bear also has extremely thick fur. The fur is hollow, providing insulation. This is what makes the polar bear waterproof. If

they were not waterproof, they would just turn into a block of ice when they jumped into the frigid water to catch their prey. It also keeps them nice and warm in the winter. In the summer, however, they get extremely hot. To cool down, they roll over on to their sides and stick their paws out. This activity sends the heat out through their pads, lowering their body temperature. Below all the fur, there is a 4 to 5 inch thick layer of fat (blubber). This blubber also serves to keep the bears warm. Occasionally, however, it gets too cold and the bear has to resort to other means of keeping warm. The bear will actually plow itself into a snowdrift and stick its rear end up to block the wind while its front end is under the snow. On the other hand when it gets too hot to stand, the

polar bear will dig itself a cave into the permafrost. The bear will keep coming back to the cave year after year. Eventually the cave can become quite deep. REPRODUCTION With polar bears, mating usually takes place in April and May on the sea ice. When the female is in heat, she will start marking her trail with several urination s a day. The male polar bears can tell instantly the tracks of a female in heat. The male will follow the tracks for several days until he finds her. When the male meets the female, there is usually another male that he must fight with for the right to mate. The winner then goes off with the female and they walk together for a couple weeks. The male polar bear will test the female constantly to see if she is ready. When she is, the two will mate several

times over about a week. After the female is pregnant she must gain a couple hundred pounds of fat to have a successful pregnancy. Also, she will build a maternity den where she is to have her cubs. After she builds her den, it takes about one to two months before she gives birth. When cubs are born, they are very tiny and only weight around 1 pound. The cubs eyes stay closed for about 30 days and their canine teeth only become apparent after about 50 days. The cubs begin to walk after about 2 months. The mother nurses the cubs for a couple more months. The cubs will stay with their mother for a couple years before they leave. Most polar bears don t reproduce until they are around the age of five. The female will probably lose her first litter. Most litters are usually twins,

however, some may be as large as four. CONCLUSION By now you can see what amazing animals polar bears really are. Today, polar bears are endangered animals and may become extinct if poachers aren t stopped. However, an agreement between several countries was recently signed saying that people can t hunt them. This may help to protect them to some degree, but in the long run they will probably be killed off, except those maintained in zoos.