Credit: Mark Maftei, Wildlife Conservation Society
The polar bear near the scientists' campsite off the Beaufort Sea. Polar bears have become increasingly confined to land as Arctic sea ice melts.
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Mama bear and cubs
Global Warming May Kill Polar Bears, Scientist
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Credit: Robert Rockwell
Polar bear on the Cape Churchill Peninsula of western Hudson Bay.
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Baby polar bear
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World's Cutest Baby Wild Animals
Though they are cuddly creatures when young, polar bear babies grow up to be ferocious predators. They are controversial zoo inhabitants, as many conservationists argue that it's unnatural to breed these violent bears in zoos, rather than in their natural habitat. However, that habitat is swiftly disappearing as the polar bear's home –the arctic ice – is diminishing rapidly due to climate change.
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Knut at the zoo
Credit: Berlin Zoo
Knut at the Berlin Zoo.
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Credit: Berlin Zoo
The Berlin Zoo's beloved polar Bear Knut, whose antics and cute demeanor charmed the world, died unexpectedly over the weekend, on March 19.
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What Big Paws You Have
Credit: Captain Budd Christman, NOAA Corps
A researcher examines the paws of a sedated polar bear in this 1982 photograph taken in Alaska. Polar bears' giant paw pads help them keep traction on ice and snow.
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Credit: Daniel J. Cox/NaturalExposures.com
A polar bear sniffs at the camera
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Credit: Wikimedia commons user Messybeast
Also known as the "grolar" or "prizzly" bear, this is a stuffed polar-grizzly hybrid at the Rothschild Museum in Tring, England
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Polar Bears Forced to Land and Water
Polar bears depend on sea ice for hunting, breeding and denning. The bears wait for seals to pop up through breathing holes in the ice, but since the ice is melting earlier and earlier in the year, polar bears are shifting their habitat to land and water, and may be missing out on hunting opportunities.
A large male polar bear returns to feed on a fin whale carcass. On land, where bears cannot hunt for seals, food is scarce and polar bears mainly depend on washed up marine mammals for food. Holmiabukta Bay, Northwestern Svalbard, Norway.
Female polar bear with her cub on a frozen lake near Cape Churchill, Canada.
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Patchy Polar Bear
This polar bear, captured and immobilized by USGS scientists, shows hair loss and oozing sores on the left side of its neck. The cause of the alopecia and lesions is still unknown.
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Polar Bears on Arctic Ice
Credit: Sophie TRAN, Laboratoire des Sciences du Climat et de l'Environnement (LSCE), distributed by EGU under a Creative Commons license.
A baby polar bear follows its mother across Arctic ice.
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Swimming Polar Bear
Credit: Paul Nicklen | National Geographic Stock | World Wildlife Fund
The rapid loss of sea ice is forcing polar bears to go for longer swims, according to research.
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Polar bear with cub
Credit: Scott Schliebe/USFWS
A polar bear and her healthy cub, a sight that could be increasingly rare in Canada's Hudson Bay.
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Credit: World Wildlife Fund
Researchers following a group of adult polar bears wearing GPS collars found a 45 percent mortality rate among the cubs of those who swam 30 miles or more at a time, as compared with an 18 percent mortality rate among the cubs of other polar bears.
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Polar Bears Evolved Just 150,000 Years Ago
Credit: U.S. Fish and Wildlife Service.
Here two polar bear cubs snuggle up. The polar bears, which evolved from brown bears, originated some 150,000 years ago, according to genetic analyses of a polar bear fossil.
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Goose Eggs Could Save Polar Bears
Polar bears hunt seals from the ice. When their icy habitat melts, the bears are forced to swim more, move north or retreat to land.