As Arctic winters warm, polar bears are faced with a troubling situation.

Following the stories of several urban kangaroos, Kangaroo Mob reveals how these metropolitan marsupials manage to survive the city, and documents the ongoing debate on how best to manage them.

Tom Murphy must make camp before dark. He's carrying everything he needs to survive -- plus his camera gear.

This grizzly bear is not sleeping. She's been in a state of hibernation since November.

This week's dirt: Walking Fish Left Fossil ‘Finprints’, Tiny Spiders With Giant Brains, Why We Still Have Body Hair, Insects Point the Way to Plastics of the Future, Buttercups Play With Light to Attract Bees, ‘Photoshopping’ Wolves for Political Points, and more.

Diving nose first through the snow's surface, this red fox searches out a meal.

Chris Morgan shares his thoughts on the recent case of polar bear cannibalism. "Each and every polar bear is facing increased every-day stress as a result of our warming planet."

This video explores the critical role of salmon in an ecosystem, as well as efforts to reintroduce salmon nutrients into streams.

This video from NATURE explores the life and death of wild salmon in the Pacific Northwest.

This week's dirt: Toads sniff for earthquakes, inbreeding doesn't faze bedbugs, ugly faces add some bite, the possible return of the woolly mammoth, and more.