![]() ![]() Superb hunters, polar bears are the most carnivorous of all bears. In fact, a polar bear running on land will easily become overheated, and many land animals are too fast for polar bears to successfully hunt. They wear a dense layer of underfur, have black skin to absorb the sun’s energy rays, and carry a layer of blubber beneath their skin, insulating them from the Arctic temperatures both on land and at sea. In the Arctic’s chilly temperatures, often well below freezing, polar bears are designed for warmth. ![]() Their iconic white coats are a means to disguise themselves against the backdrop of their frozen snow-covered hunting grounds. © Carrie Vonderhaar, Ocean Futures Society While polar bears are part of the bear family, including brown and grizzly bears, these enormous mammals have evolved incredible and unique adaptations to survive life in the frigid waters of the Arctic and surrounding landmasses, the only region in the world where polar bears exist. C'est la prédation de ces classes d'âges terme qui permet l'apport énergétique maximal à l'ours, tout en causant le moins de tort à la population de proies.Standing up to nine feet tall and weighing in over one thousand pounds, polar bears are the largest land carnivores in the world. Les phoques âgés de moins de deux ans, sont les plus fréquemment tués. Les régions de glaces hummockées, le meilleur habitat de reproduction du phoque annelé, sont chassées par, l'ours polaire avec moins de succès que les autres types de glace, peut-être à cause de facteurs tels que la complexité des repaires de naissance et une certaine confusion olfactive. Les ours polaires tuent surtout les phoques nouveau-nés. Le phoque barbu Erignathus barbatus semble constituer une espèce fréquemment chassée par l'ours polaire au sud-est de la Terre de Baffin. ![]() Les types de glace sur lesquels chassent îes ours sont différents entre le grand Nord et la région sud-est de la Terre de Baffin, Aucune différence n'a été notée dans les proportions des essais réussis. Dans le grand Nord et à l'est de la Terre de Baffin, la déprédation des repaires sous-nivéaux du phoque annelé Phoca hispida est fréquente. ![]() La prédation sur les phoques par Tours polaire Ursus maritimus est négligeable dans le Golfe d'Amundsen. Data are presented to show that harvesting these age-classes provides the maximum return of energy to the bear and results in the least harm to the prey population. Seals under 2 years of age are those most frequently killed by bears. Several factors such as the complexity of birth lairs and possible olfactory confusion might account for this. The prime breeding habitat of ringed seals located in ice hummock areas is less successfully preyed upon by bears than other ice types. Polar bears mainly kill newborn pups in their birth lairs. There is strong evidence that the bearded seal, Erignathus barbatus, is an important prey species of the polar bear in southeastern Baffin Island. However, no difference was seen in the proportion of successful kills. The ice types hunted by bears differed between the High Arctic and southeastern Baffin Island. In the High Central and Eastern Arctic, and along southeastern Baffin Island, bear predation of the subnivean lairs of ringed seals, Phoca hispida, was common. Predation of seals by the polar bear, Ursus maritimus, was not significant in the Western Arctic. ![]()
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