As the world's first national park, Yellowstone has long served as a model for the protection of wilderness around the world. For Americans it has become a source of great national pride, not least because it encapsulates all our popular notions of what a wilderness should be - vast, uninhabited, with spectacular scenery and teeming with wildlife.

A natural history portrait of a year in Yellowstone, following the fortunes of America's wildlife icons as they face the challenges of one of the most extraordinary wildernesses on Earth.