Starving polar bears turn to cannibalism

By Jonathan Liew
Published: 2:40PM GMT 08 Dec 2009 New pictures show that polar bears are beginning to cannibalise each other as global warming destroys their hunting grounds. The images, taken in Hudson Bay, Canada, around 200 miles north of the town of Churchill, Manitoba, show a male polar bear carrying the bloodied head of a polar bear cub it has killed for food. Polar bears usually subsist on seals, which they hunt from a platform of sea ice. But the melting of sea ice as a result of rising global temperatures has made it more difficult for polar bears to hunt seals at sea, confining the bears to land. This has led to malnourishment and starvation as polar bears are unable to build sufficient fat reserves for winter. Drowning is also more common as bears are forced to swim further out to sea to find food. … Last month tourists on a guided tour of the area were reported to be distressed after witnessing a male bear eating a cub. …

December 7, 2009 – Freeze-up ran weeks late this year on Hudson Bay, and the polar bears that gather near Churchill to wait for the ice to form showed signs of stress. “Research shows that the average body condition of the Western Hudson Bay polar bears has been declining for almost 30 years,” says Dr. Andrew Derocher, a leading polar bear scientist who serves on PBI’s Advisory Council. “If they’re forced to wait until December to return to the sea ice this continues to take a toll on the bears as they burn one kilowatt of stored body fat every day they’re not hunting.” Scientists believe that the decline in body condition and this year’s late freeze-up may have contributed to this year’s higher-than-normal observations of cannibalism of cubs by adult males in the Western Hudson Bay population. Manitoba Conservation has confirmed four cases of cannibalism this year and are investigating four others. In a typical year, there are one or no cub deaths by male bears. “The weight of evidence is that cannibalism and infanticide has been uncommon in Churchill,” says Derocher. “It certainly wasn’t this year. It’s an unusual event that should be reported.” Photographer Daniel J. Cox of Natural Exposures captured grisly images of a male bear preying on a cub this fall. Though graphic, it’s important for the world to understand the pressures on the bears by a changing Arctic. To view his gallery of images, click here. …

Cannibalism in Hudson Bay Bears