September 24th, 2008

JIM WANT

(no subject)

Polar bears resort to cannibalism as Arctic ice shrinks

This past summer, the Arctic sea ice dwindled to its second lowest level. Arctic sea ice is usually 1 to 3 meters, or as much as 9 feet thick. It grows during autumn and winter and shrinks in the spring and summer.

So, just how much ice is disappearing?

Less than 30 years ago, there would still be 7 million square kilometers or 2.5 million square miles of ice left at the end of an Arctic summer. That's now dropped by almost 40 percent.

"Seven million square kilometers roughly corresponds to an area of the lower 48 United States. So back in the early 1980s, the lower 48 states would be covered in sea ice in the summer," Meier said. "Now we've essentially lost sea ice east of the Mississippi River and even beyond. So that's a significant amount of area."

The best known consequence of disappearing sea ice in the Arctic is the loss of the polar bear habitat. Learn more about polar bears and their habitat.

"The Arctic sea ice melt is a disaster for the polar bears," according to Kassie Siegel, staff attorney for the Center for Biological Diversity. "They are dependent on the Arctic sea ice for all of their essential behaviors, and 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."

Scientists have noticed increasing reports of starving Arctic polar bears attacking and feeding on one another in recent years. In one documented 2004 incident in northern Alaska, a male bear broke into a female's den and killed her.

In May, the U.S. Department of Interior listed the polar bear as a "threatened" species under the Endangered Species Act. In a news release, U.S. Interior Secretary Dirk Kempthorne stated, "loss of sea ice threatens and will likely continue to threaten polar bear habitat. This loss of habitat puts polar bears at risk of becoming endangered in the foreseeable future, the standard established by the ESA for designating a threatened species."



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