Strange Behavior by Polar Bears

Author: Bradford Lystra

The ice that covers the Arctic Ocean has been shrinking as the Earthgrows warmer, and that's making it harder for polar bears to hunt.Scientists have seen three recent examples where polar bears found foodby stalking, killing and eating other polar bears. The scientists havebeen studying polar bears in the Arctic for more than 30 years, and thisis the first time they've documented this sort of cannibalism.Steven Amstrup leads polar bear research for the US Geological Survey atits Alaska Science Center. He helped write a report that was publishedthis spring in the journal Polar Biology. He says the bears might besuffering from changes in the Arctic climate."The sea ice has been changing dramatically. It has pulled away from thenorth coast much farther then it used to. This may place polar bears ina disadvantage nutritionally. They're either stuck on land where thereis essentially nothing for them to eat, or they have to go offshorewhere hunting opportunities may be more limited. These animals might bestressed and some of them might turn to cannibalism to survive."Polar bears occasionally kill each other and even eat each other, butthose incidents occur during fights over food or mating. Amstrup sayscannibalism is different. He says these bears were intentionallystalking and killing other polar bears.Amstrup says the loss of ice cover on the Arctic Ocean is a loss ofhabitat for the polar bears"It's critical to understand that polar bears are entirely dependent onthe sea ice for their nutrition."Environmental groups recently signed a petition to ask the U.S.government to list the bears as a threatened species. The U.S. Fish andWildlife Service is responsible for making a decision.


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