In this undated image released by Discovery Channel/BBC, polar bears walk on ice floes during the filming of "Frozen Planet," a seven-part series premiering with the first two hours Sunday, March 18, ... more 
In this undated image released by Discovery Channel/BBC, polar bears walk on ice floes during the filming of "Frozen Planet," a seven-part series premiering with the first two hours Sunday, March 18, at 8 p.m. EDT on Discovery. (AP Photo/Discovery Channel/BBC, Jason Roberts) less 
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Associated Press | Photo By Discovery Channel/BBC, Jason Roberts
Wed, Mar 14, 2012 7:41 AM EDT