Polar Bear Cannibalism Comes Early

While cannibalism is common among polar bears during the spring mating season, eight cases have been reported so far this fall in Churchill, Manitoba. Environmentalists fear that the thinning sea ice and reduced hunting range could be to blame for this early outbreak of polar bear cannibalism. Ursus maritimus males have been known to eat polar bear cubs before and after impregnating females. This new behavior is thought to be less instinctual, and more a drive to keep food in their bellies during a mild winter where long-distance swimming and hunting difficulties have made it tough for the bears to survive.

According to the US Geological Survey, the polar bear population in western Hudson Bay has shrunk by almost 200 bears in the last 17 years. "They are dependent on the Arctic sea ice for all of their essential behaviors," said Kassie Siegel of the Center for Biological Diversity. "As the ice melts and global warming transforms the Arctic, polar bears are starving, drowning, even resorting to cannibalism because they don't have access to their usual food sources." Some scientists believe that the arctic may be ice-free by 2013.

Inner-species killing is common among polar bears, leading skeptics to claim that these reports are meant to sensationalize what's happening in the arctic. Polar bears kill each other for population control, reproductive advantage, and social dominance. The first confirmed cannibalistic killing between adult polar bears happened in 2004, when a male polar bear pounced a female that had just given birth in her den and dragged her across the snow in order to eat part of her carcass. The newly born cubs suffocated when the den collapsed during the attack. Environmentalists believe that choosing to kill females indicates that polar bears are killing for lack of prey rather than for social status or breeding preference.