THE BLOG

Polar Bear Swims for 9 days in Search of Sea Ice

01/26/2011 08:22 pm ET | Updated May 25, 2011

One of Alaska's own polar bear experts is making headlines this week with a new revelation about the toll climate change is taking on polar bears as a result of melting sea ice. A group of scientists recently documented a mother bear's "epic nine-day swim in search of ice" in the waters of the Beaufort Sea.

"We are in awe that an animal that spends most of its time on the surface of sea ice could swim constantly for so long in water so cold," George M. Durner told BBC News, which reported the findings Tuesday. Durner is a research zoologist with the U.S. Geological Survey in Anchorage at the Alaska Science Center.

With data collected over a two-month period in 2008, Durner and his colleagues chronicled the bear's eastward journey along the Alaska coast, during which she made that incredible nine-day, 426-mile swim from land to floating pack ice over the sea's deep waters. Along the way, she lost her yearling cub and 22 percent of her body weight: more than 100 pounds.

"Our observation confirms that yes, indeed, polar bears are capable of, they have the ability to undergo these extraordinary behaviors such as long distance swimming. No one else has been able to provide data like this before," Durner said in an interview from his Anchorage office Tuesday.

The comprehensive data comes from a unique mix of hi-tech gadgets that were affixed to the bear in August 2008, each equipped with computer chips that recorded and preserved the data that scientists were able to download two months later, when the bear was again captured.

Through satellite tracking, motion detectors and thermometers, they kept tabs on her every hour of every day. They not only knew where she was but also whether she was walking or swimming, resting or active, and how warm or cold it was outside or in the water and, with a sensor buried in the fat beneath her skin, they recorded her own body temperature -- a blend of gadgets designed to assist not only the USGS ongoing studies, but also a University of Wyoming study looking specifically at the physiology of polar bear on land and sea ice during summer in the Beaufort Sea. For scientists, having all of the technology on a single animal was a rare expedition that, as best as it could, let them travel alongside the mother bear via data diary.

Read the entire story at Alaska Dispatch.