Today’s AP reports that aerial surveys conducted by the Minerals Management Service on August 16 recorded 9 polar bears swimming far from shore or any pack ice. As Arctic sea ice disappears, recording incidents of such long-distance swimming is becoming increasingly common.
Steven Amstrup, senior polar bear scientist for the U.S. Geological Survey in Anchorage, said the bears could have been on a patch of ice that broke up northwest of Alaska's coast.
"The bears that had been on that last bit of ice that remained over shallow shelf waters, are now swimming either toward land or toward the rest of the sea ice, which is a considerable distance north," he said in an e-mail response to questions.
It probably is not a big deal for a polar bear in good condition to swim 10 or 15 miles, Amstrup said, but swims of 50 to 100 miles could be exhausting.
"We have some observations of bears swimming into shore when the sea ice was not visible on the horizon," he said. "In some of these cases, the bears arrive so spent energetically, that they literally don't move for a couple days after hitting shore."
The risk of increased polar bear drownings is one of many affects of global warming and receding Arctic sea ice on polar bears about which biologists have long been concerned. These concerns first surfaced after a mass polar bear drowning off the coast of Alaska, where up to twenty-seven polar bears may have perished during a single storm. Writing about this (and other) incidents in its decision to list the polar bear as a threatened species, the U.S. Fish and Wildlife noted that
This suggests that drowning related deaths of polar bears may increase in the future if the observed trend of recession of pack ice with longer open-water periods continues.
What is the Bush Administration’s response? Why, new proposed regulations that attempt to foreclose any avenue to address global warming pollution through the Endangered Species Act, of course! Speaking of which, yesterday NRDC and over 100 other conservation groups, representing millions of Americans, requested that the Department of the Interior extend its comment period on the proposed regulations and hold public hearings on its proposed regulation. Let’s hope they listen.