Looking for a story/book

Some time back I read something where Our Hero was on the run from some not nice people. It may have been winter. At the very least the water was cold enough to cause hypothermia fairly quickly.

He went into the water either upstream of a beaver pond or in the pond itself and managed to find the underwater entrance to the beaver lodge.

He climbed out and curled up with the beavers to warm up while the bad guys eventually gave up figuring he'd died in the water.

Ring any bells?