Polar Bear Near Churchill, Manitoba (image) University of Washington Share Print E-Mail Caption A polar bear walks along an expanse of open water at the edge of Hudson Bay near Churchill, Manitoba, in 2011. The bears need pack ice to hunt for food, primarily seals, but climate change brings open water more often than it used to. Polar bears have been listed as a threatened species. Credit Cecilia Bitz/U. of Washington Usage Restrictions News use only Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.