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in a warmer world, polar bears will lose out to grizzlies

More bad news for polar bears on the climate change front- a new study by evolutionary biologists at the Univeristy of California, Los Angeles, predicts that as northern climates warm and the habitat ranges of polar bears and grizzly bears overlap more, polar bears will be outcompeted for food.

Milder temperatures in the high Canadian boreal forest and tundra are already causing grizzlier bears to push further north. At the same time, the Arctic sea ice that polar bears depend on to hunt fish and seals is shrinking, which is causing the bears to migrate further south in search of food.

The study, which used 3-D modeling to compare the skull and jaw strength of the closely related species, found that polar bears are ill-suited for the tougher chewing demands imposed by a more vegetarian diet they will likely need to adopt. Grizzly bears, whose jaws are adapted for breaking up tough grasses, bark and berries, will not be required to alter their diet much as they migrate north.

The species range of grizzlies and polar bears has already begun to overlap. In 2006, the first confirmed hybrid of a grizzly bear and a polar bear was shot by a Canadian hunter.

This study was also reported by Facts About Climate Change