Discover the habits of these giant carnivores and find out the polar bears' secrets for surviving in the Arctic.

Scientists hoping to learn more about polar bears face an exhausting challenge: spending hours searching over huge territories and enduring harsh weather.

What type of dog makes the best sled dog? What commands does a musher use? What equipment is required to race? In Dogsledding 101, you can learn all this and more.

The powerful McNeil River Falls is a very popular nursery spot for growing grizzly bears. Every summer, hundreds of the huge animals gather at the falls to feast on migrating salmon and find mates.

Newborn bears arrive each January and February weighing less than a pound, nearly hairless and mostly helpless. But they put on weight fast, and by their first summer are able to follow their moms on hunting expeditions.

Ironically, the powerful, dedicated canines profiled in Sled Dogs: An Alaskan Epic are little more than mutts. They are mixed-breed huskies that have endurance.

Ironically, the powerful, dedicated canines profiled in Sled Dogs: An Alaskan Epic are little more than mutts. They are mixed-breed huskies that have endurance.

Ironically, the powerful, dedicated canines profiled in Sled Dogs: An Alaskan Epic are little more than mutts. They are mixed-breed huskies that have endurance.

Ironically, the powerful, dedicated canines profiled in Sled Dogs: An Alaskan Epic are little more than mutts. They are mixed-breed huskies that have endurance.

Ironically, the powerful, dedicated canines profiled in Sled Dogs: An Alaskan Epic are little more than mutts. They are mixed-breed huskies that have endurance.