Nature: Polar Bears

This episode from the popular "Nature" series homes in on the habits of polar bears, the great white descendents of the grizzly, which have evolved to survive and thrive in the Arctic but whose very existence is now threatened by climate change. As their habitat disappears, these glorious beasts struggle to maintain their population, even as grizzlies move in on their territory. Also included is the bonus program "Showdown at Grizzly River."