Polar Bear Essay Example for Free

Polar Bear EssayThe polar abide (Ursus maritimus) is a bear native by and large within the Arctic circle encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the worlds largest land carnivore and to a fault the largest bear, together with the omnivorous Kodiak bear, which is approximately the same size. 3 An gravid male weighs around 350-680 kg (770-1 ,500 while an adult female is about half that size.Although it is closely related to the brown bear, it has evolved to occupy a narrow bionomic niche, with many body characteristics adapted for cold emperatures, for moving across s presently, ice, and unresolved water, and for hunting the seals which make up most of its diet. 5 Although most polar bears are born on land, they spend most of their time at sea (hence their scientific name meaning maritime bear) and can hunt consistently only from sea ice, so spend much of the year on the frozen sea. The polar bear is classified as a vulnerable sp ecies, with 8 of the 19 polar bear subpopulations in decline. 6 For decades, unrestricted huntingclarification eeded raised foreign concern for the future of the species populations have rebounded after controls and quotas began to take effect. citation needed For thousands of years, the polar bear has been a key fgure in the material, spiritual, and cultural life of Arctic indigenous peoples, and the hunting of polar bears remains important in their cultures. The IIJCN now lists global warming as the most significant threat to the polar bear, primarily because the melting of its sea ice home ground reduces its ability to find sufficient food.The II-JCN states, If climatic trends continue polar bears may draw extirpated from most of their range within 100 years. 7 The polar bear was listed as a threatened species infra the Endangered Species Act by the United States Department of the Interior in 2008. Habitat The polar bear is often regarded as a marine mammal because it spends many months of the year at sea. 28 Its preferred habitat is the annual sea ice covering the waters over the continental shelf and the Arctic inter-island archipelagos.These areas, cognize as the Arctic ring of life, have high biological productivity in comparison to the profoundly waters of the high The polar bear tends to frequent areas where sea ice meets water, such as polynyas and leads (temporary stretches of open water in Arctic ice), to hunt the seals that make up most of its diet. 30 Polar bears are and so found primarily along the perimeter of the polar ice pack, rather than in the Polar turning point close to the North Pole where the density of seals is low. 1 Annual ice contains areas of water that appear and disappear end-to-end the year as the weather changes. Seals migrate in response to these changes, and polar bears must follow their prey. 29 In Hudson Bay, James Bay, and some other areas, the ice melts completely separately summer (an event often referred to a s ice-floe breakup), forcing polar bears to go onto land and wait through the months until the next freeze-up. 29 In the Chukchi and Beaufort seas, polar bears retreat each summer to the ice further north that remains frozen year-round.