New proof that polar bears turn to ‘cannibalism’ to survive

This year has been an especially hard one for the polar bear, with their population making the list of "at risk" species and their habitat continuously shrinking. But recent photo evidence from the Arctic shows that some of these bears may be faced with an even more gruesome reality.

Scientists say there are an increasing number of polar bears turning to cannibalism in order to survive as their habitat continues to change.

World-renowned polar bear expert Dr. Ian Stirling of Environment Canada and environmental photojournalist Jenny Ross managed to witness a particularly startling incident of an adult bear carrying the carcass of a young cub. Ross caught the scene through her telephoto lens, and the photo, seen here in this BBC story, might be shocking to some.

But Stirling says that cannibalism isn't new to polar bears, although there has definitely been an increase in the number eating younger cubs as it gets harder for the bears to hunt seals, their primary source of food.

"We found four bears that had been cannibalized, we found a couple that had starved to death, and these are things that I had never seen before in the 30 years that I have worked in that part of the world" Stirling says in a CBC National News report, describing his 2009 work in the Beaufort Sea, north of Alaska.

Stirling and Ross shared the story behind the photograph in a recent Arctic journal article, and Ross recounted their experience at the American Geophysical Union Fall Meeting this week.

Ross said that she could see the polar bear through her camera as she approached it by boat, but only saw up close that it was a young cub in the bear's jaws.

"As soon as the adult male became aware that a boat was approaching him, he basically stood to attention - he straddled the young bear's body, asserting control over it and conveying 'this is my food'," Ross said in the BBC story.

"He then picked up the bear in his jaws and, just using the power of his jaws and his neck, transported it from one floe to another. And eventually, when he was a considerable distance away, he stopped and fed on the carcass."

Retreating ice in the Arctic region shoulders a lot of the blame for why the polar bears are turning to cannibalism to survive. With open water replacing the ice platforms they normally hunt from, the bears have been forced to look for alternate food sources.

But the twist in this story is that the practice isn't just happening in the wild: there have been odd cases of polar bears killing and eating younger cubs in controlled environments, too. A zoo in Nuremberg reported in 2008 that a mother polar bear ate one of her twin cubs. According to one Inuit leader, however, an adult polar bear eating a cub is actually quite a normal occurrence.