POLAR BEARSPOLAR BEARS

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Basic information on Basic information on Polar BearsPolar Bears

The The polar bearpolar bear is a is a bearbear native to the native to the Arctic OceanArctic Ocean and its and its surrounding seas. The world's largest predator found on land, an adult surrounding seas. The world's largest predator found on land, an adult male weighs around 300–600 kg (660–1320 lb), while an adult female male weighs around 300–600 kg (660–1320 lb), while an adult female is about half that size. Although it is closely related to the is about half that size. Although it is closely related to the brown bearbrown bear, , it has evolved to occupy a narrow it has evolved to occupy a narrow ecological nicheecological niche, with many body , with many body characteristics adapted for cold temperatures, for moving across characteristics adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting the snow, ice, and open water, and for hunting the sealsseals which make up which make up most of its diet.As it can hunt consistently only from most of its diet.As it can hunt consistently only from sea icesea ice, the polar , the polar bear spends much of the year on the frozen sea, although most polar bear spends much of the year on the frozen sea, although most polar bears are born on landbears are born on land..

Polar bears are the largest land carnivore. Polar bears are the largest land carnivore. 2. Male polar bears (boars) grow two to three times the size of female 2. Male polar bears (boars) grow two to three times the size of female

polar bears (sows). Boars weigh about 350 to more than 650 kg (772-polar bears (sows). Boars weigh about 350 to more than 650 kg (772-1,433 lb.) and are about 2.5 to 3 m (8.2-9.8 ft.) long (Stirling, 1988). 1,433 lb.) and are about 2.5 to 3 m (8.2-9.8 ft.) long (Stirling, 1988).

3. Sows weigh about 150 to 250 kg (331-551 lb.) and are about 2 to 3. Sows weigh about 150 to 250 kg (331-551 lb.) and are about 2 to 2.5 m (6.6-8.2 ft.) long. Pregnant females can weigh as much as 500 2.5 m (6.6-8.2 ft.) long. Pregnant females can weigh as much as 500 kg (1,102 lb.) (Stirling, 1988). kg (1,102 lb.) (Stirling, 1988).

4. The largest polar bear ever recorded was a male weighing 1,002 kg 4. The largest polar bear ever recorded was a male weighing 1,002 kg (2,209 lb.) and measuring 3.7 m (12 ft.) long (Domico, 1988).(2,209 lb.) and measuring 3.7 m (12 ft.) long (Domico, 1988).

Adaptations or something Adaptations or something unique about Polar Bearsunique about Polar Bears

Polar Bear adaptation to the cold and unforgiving Arctic climate is one of nature's mysteries. The shifting Polar Bear adaptation to the cold and unforgiving Arctic climate is one of nature's mysteries. The shifting sea ice, where polar bear live, is one of the unkindest and grimmest climates in the world. It's only in sea ice, where polar bear live, is one of the unkindest and grimmest climates in the world. It's only in recent evolutionary period that bears adjusted to arctic sea life. It commenced during the Ice Age, in the recent evolutionary period that bears adjusted to arctic sea life. It commenced during the Ice Age, in the northern seas, when the seals needed to breathe and reproduce on the water's surface. From this, the northern seas, when the seals needed to breathe and reproduce on the water's surface. From this, the seals became a rich year-round food source within reach of a population of brown bears, who then began seals became a rich year-round food source within reach of a population of brown bears, who then began to inhabit the ice, developing into something similar to the polar bear of today, around 100,000 years ago. to inhabit the ice, developing into something similar to the polar bear of today, around 100,000 years ago.

Weighing around 330 to 1,760 pounds, the length of the polar bear's body is about 6.6 to 10 feet. The male Weighing around 330 to 1,760 pounds, the length of the polar bear's body is about 6.6 to 10 feet. The male body is generally larger than the female. The polar bear, similar to the brown bear, is heavy and stocky. It body is generally larger than the female. The polar bear, similar to the brown bear, is heavy and stocky. It has an long neck and small head. Its fur, normally white, occasionally appears yellow, due to oxidation. has an long neck and small head. Its fur, normally white, occasionally appears yellow, due to oxidation.

A polar bear has black skin, which aids it's adjustment to the Arctic temperature, absorbing and holding A polar bear has black skin, which aids it's adjustment to the Arctic temperature, absorbing and holding heat from the sunlight. It is definitely well dressed for the weather with a layer of fat more than 4 inches heat from the sunlight. It is definitely well dressed for the weather with a layer of fat more than 4 inches thick, providing efficient insulation. The dense fur on its feet (its foot is about 9 inches wide and 12 inches thick, providing efficient insulation. The dense fur on its feet (its foot is about 9 inches wide and 12 inches long) allows for warmth and traction. As each foot is so huge, it acts as a functional snowshoe. long) allows for warmth and traction. As each foot is so huge, it acts as a functional snowshoe.

It adjusts well to swimming with its broad forepaws that serve as paddles and when swimming underwater It adjusts well to swimming with its broad forepaws that serve as paddles and when swimming underwater it lays the small ears flat for protection, and its nostrils close under water. It paddles at about 6 and one-it lays the small ears flat for protection, and its nostrils close under water. It paddles at about 6 and one-half miles per hour --paws only, hind paws trailing--and can stay submerged for about 2 minutes. The hairs half miles per hour --paws only, hind paws trailing--and can stay submerged for about 2 minutes. The hairs of its waterproof coat are hollow which is a good insulator and increases the bear's buoyancy when of its waterproof coat are hollow which is a good insulator and increases the bear's buoyancy when swimming. swimming.

A polar bear has a keen sense of smell, sensing prey at a distance of about 20 miles. Although little is A polar bear has a keen sense of smell, sensing prey at a distance of about 20 miles. Although little is known about its sense of touch (its eyesight and hearing is acute), a polar bear is able to manipulate known about its sense of touch (its eyesight and hearing is acute), a polar bear is able to manipulate various objects with surprising dexterity. various objects with surprising dexterity.

With canine teeth larger and malariform teeth sharper than those of different bears, the polar bear is the With canine teeth larger and malariform teeth sharper than those of different bears, the polar bear is the most carnivorous North American bear. most carnivorous North American bear.

A polar bear inhabits Arctic islands, sea ice, and water and continental coastlines. It favors the sea ice A polar bear inhabits Arctic islands, sea ice, and water and continental coastlines. It favors the sea ice habitat, with water channels or cracks through the ice, next to continental coastlines or islands. A lot of habitat, with water channels or cracks through the ice, next to continental coastlines or islands. A lot of polar bears spend part of the year on land, although in warmer climates a bear might become isolated. polar bears spend part of the year on land, although in warmer climates a bear might become isolated. Most pregnant females spend the autumn and winter on land in maternity dens. Most pregnant females spend the autumn and winter on land in maternity dens.

A polar bear journeys throughout the year within individual home ranges, which are likely to be larger than A polar bear journeys throughout the year within individual home ranges, which are likely to be larger than for other mammal species because of the shifts in sea ice from year to year and even season to season. for other mammal species because of the shifts in sea ice from year to year and even season to season. Small home ranges (19,000 to 23,000 miles) can be observed near Canadian Arctic Islands, while bigger Small home ranges (19,000 to 23,000 miles) can be observed near Canadian Arctic Islands, while bigger home ranges can be viewed in the Bering or Chukchi Sea areas. The polar bear remains in the general area home ranges can be viewed in the Bering or Chukchi Sea areas. The polar bear remains in the general area during the same season. A polar bear can travel 19 miles or more per day for several days, although some during the same season. A polar bear can travel 19 miles or more per day for several days, although some are capable of much more than that. One can only hope that polar bear adaptation will carry on, as their are capable of much more than that. One can only hope that polar bear adaptation will carry on, as their habitat area shrinks and the pressures of civilization continue to encroach on the the natural homes where habitat area shrinks and the pressures of civilization continue to encroach on the the natural homes where the polar bear dwell.the polar bear dwell.

Ancestors of the Polar Ancestors of the Polar Bears and living relativesBears and living relatives

The sea ice of the Arctic Ocean and the connected The sea ice of the Arctic Ocean and the connected frozen seas is home to the largest and most frozen seas is home to the largest and most predatory of the bear family. All bears alive today predatory of the bear family. All bears alive today evolved 22 million years ago from a common evolved 22 million years ago from a common ancestor — the Ursavus of Asia. Polar bears (ancestor — the Ursavus of Asia. Polar bears (Ursus Ursus maritimusmaritimus) evolved from a group of brown [CL1] ) evolved from a group of brown [CL1] bears (bears (Ursus arctosUrsus arctos) over 200,000 years ago, which ) over 200,000 years ago, which became isolated from other brown bear populations became isolated from other brown bear populations by glaciers, possibly in Siberia. It is easy to imagine by glaciers, possibly in Siberia. It is easy to imagine the evolutionary change in brown bears that the evolutionary change in brown bears that inhabited a northern coast during a climatic cooling inhabited a northern coast during a climatic cooling period, when food as tempting as unwary seal pups period, when food as tempting as unwary seal pups can be found offshore. can be found offshore.

Habitat the Polar Habitat the Polar BearsBears live inlive in

Well Polar Bears live in the cold and Well Polar Bears live in the cold and windy northern arctic .The Polar windy northern arctic .The Polar Bears are also found throughout the Bears are also found throughout the circumpolar arctic on pack ice ,along circumpolar arctic on pack ice ,along or near coasts ,and on islands.Well or near coasts ,and on islands.Well Polar Bears share there habitat with Polar Bears share there habitat with indegenious people. Another thing is indegenious people. Another thing is that Polar Bears that Polar Bears