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Polar bears under watch

By: chief on Dec. 15, 2011, 8:01 a.m.
entrance to polar bear den

Photo: USGS

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Home sweet home

This is the opening to a polar bear den near the Alaska coast. Polar bears don't hybernate the way other bears do, but they do use dens. A pregnant mother bear will remain in the den for about three months after she gives birth.