Polar bear population facts are somewhat sketchy since much of the areas that Polar bears live in is inhospitable and sparsely populated. They largely live on the ice flows upon which they depend for food, reproduction and child rearing. This makes tracking them for scientific research complicated.
They are native to Canada, Greenland, Alaska and parts of eastern Russia being widely scattered in Canada, from the northerly Arctic islands and south to the Hudson Bay. There have been sightings of Polar bear tracks as far north as the North Pole, however scientists believe that very few bears travel beyond 82 degrees North latitude. The northern Arctic Ocean has insufficient food available to support them.
No completely accurate census exists on which to base a global population approximation, but wildlife scientists use a working estimate of around 20,000 to 25,000 bears with about 60% of those dwelling in Canada's far North.
continued...In more populated regions where long-term analyses are obtainable, populations are bearing witness to signs of strain due to contracting sea ice. Canada's Western Hudson Bay population has deteriorated 22% since the early 1980s. The declines have been directly associated to an earlier ice break-up on Hudson Bay. A long-term study of the Southern Beaufort Sea population, which traverses the northerly seashore of Alaska and western Canada, has unveiled a decline in cub survival rates and in the weight and skull size of adult males. Such declines were noted in Western Hudson Bay bears preceding the population drop-off there. Another population listed as slumping is Baffin Bay. According to the latest report from the Polar Bear Specialist Group, the harvest levels from Nunavut when aggregated with those from Greenland (which were believed to be much lower than they really are) has resulted in this shared population to be in a non-sustainable harvest position, signifying that the population is in heavy danger of a severe decline. The Polar bear harvest is thought to be many times above what is sustainable.
The available data strongly suggests that Polar bear populations are in steep decline. Global climate change which is breaking up Polar ice packs is a chief suspect in the decline. However, research is not conclusive and further study is required.
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