TOM MANGELSEN / Male Resplendent quetzal (Pharomachrus mocinno) perched at its nest hole, El Triunfo Biosphere Reserve, Sierra Madre de Chiapas, Mexico.

TOM MANGELSEN / Polar Bear (Ursus maritimus) portrait, Canada

TOM MANGELSEN / Polar bear swimming with cubs {Ursus maritimus} Arctic

TOM MANGELSEN / Peregrine falcon diving, Arctic. Peregrines are the fastest animals in the air, recorded at 200mph in a dive!

TOM MANGELSEN / Mule deer (Odocoileus hemionus), female nuzzling young. Montana, USA

TOM MANGELSEN / Polar bear watches Arctic fox Churchill. Canada

TOM MANGELSEN / American bald eagles on perch (Haliaeetus leucocephalus) Alask

TOM MANGELSEN / Moose by lake, Alaska (Alces alces) Denali NP US

TOM MANGELSEN / Wild Grey wolf portrait, Denali NP (Canis lupus) Alaska

TOM MANGELSEN / Polar Bear mother and cubs (Ursus maritimus) Churchill, Manitoba, Canada

TOM MANGELSEN / Brown bear (Ursus arctos) Kodiak NP, Alaska

TOM MANGELSEN / Stoat / Ermine in winter coat (Mustela erminea) Grand Teton NP Wyoming, USA

TOM MANGELSEN / Siberian Tiger cub, orphaned (Panthera tigris altaica)

TOM MANGELSEN / Siberian Tiger cub orphan (Panthera tigris altaica) Omaha Zoo, Nebraska

TOM MANGELSEN / Arctic Fox in snow, Canada. (Vulpes lagopus)

TOM MANGELSEN / Arctic Fox sitting at sunset. Canada (Vulpes lagopus)

TOM MANGELSEN / Arctic Fox on ice, Canada (Vulpes lagopus)

TOM MANGELSEN / Arctic Fox sitting portrait, Canada (Vulpes lagopus)

TOM MANGELSEN / Polar Bear resting on snow, Canada

TOM MANGELSEN / Polar Bear,Canada (Ursus maritimus)

TOM MANGELSEN / Bohemian waxwings eating berries (Bombycilla garrulus) Montana

TOM MANGELSEN / Northern cardinal fluffed up in tree. (Cardinalis cardinalis) Montana

TOM MANGELSEN / Coyote in snow in Yellowstone NP (Canis latrans) Wyoming, USA

TOM MANGELSEN / Stoat / Ermine in winter coat by wood pile (Mustela erminea) Grand Teton NP, USA

TOM MANGELSEN / Polar bears relaxing, Hudson Bay Canada

TOM MANGELSEN / Polar bears, Canadian Arctic

TOM MANGELSEN / Polar bears (Ursus maritimus) on ice at sunset. Hudson Bay, Canada.

TOM MANGELSEN / Polar bear head portrait (Ursus maritimus) Hudson Bay, Canada

TOM MANGELSEN / Dall sheep / Thinhorn sheep (Ovis dalli) two rams resting, Denali National Park, Alaska, USA.

TOM MANGELSEN / Coyote (Canis latrans) travelling on a sand bar, in autumn with trees reflecting in Snake River, Oxbow Bend, Grand Teton National Park, Wyoming, USA.

TOM MANGELSEN / Litter of Coyote (Canis latrans) pups emerging from den. Yellowstone National Park, Wyoming, USA, June.

TOM MANGELSEN / Coyote (Canis latrans) walking through deep snow, Yellowstone National Park, Wyoming, USA. February.

TOM MANGELSEN / Coyote (Canis latrans) walking in snow, Yellowstone National Park, Wyoming, USA. February.

TOM MANGELSEN / Coyote (Canis latrans) with ears back standing in snow, Yellowstone National Park, Wyoming, USA. February.

TOM MANGELSEN / Coyote (Canis latrans) portrait in snow, Yellowstone National Park, Wyoming, USA. February.

TOM MANGELSEN / Coyote (Canis latrans) with standing in snow, Yellowstone National Park, Wyoming, USA. February.

TOM MANGELSEN / Coyote (Canis latrans) carrying fish prey through snow, with standing in snow, Grand Teton National Park, Wyoming, USA. February.

TOM MANGELSEN / Coyote (Canis latrans) standing on a charred fallen tree in patchy snow, Yellowstone National Park, Wyoming, USA. October.

TOM MANGELSEN / Coyote (Canis latrans) standing in patchy snow, Yellowstone National Park, Wyoming, USA. October.

TOM MANGELSEN / Coyote (Canis latrans) walking through snow along the Yellowstone River in Yellowstone National Park, Wyoming, USA. October.

TOM MANGELSEN / Coyote (Canis latrans) pups playing near their den, Yellowstone National Park, Wyoming, USA. June.

TOM MANGELSEN / Coyote (Canis latrans) female standing on boulders, Yellowstone National Park, Wyoming, USA. June.

TOM MANGELSEN / Coyote (Canis latrans) pup standing in grass, Yellowstone National Park, Wyoming, USA. June.

TOM MANGELSEN / Coyote (Canis latrans) female walking away from nursing pups, Yellowstone National Park, Wyoming, USA, June.

TOM MANGELSEN / Coyote (Canis latrans) female nursing pups, Yellowstone National Park, Wyoming, USA, June.

TOM MANGELSEN / Horned guan (Oreophasis derbianus) standing in a tree, El Triunfo Biosphere Reserve, Sierra Madre de Chiapas, Mexico.

TOM MANGELSEN / Male Resplendent quetzal (Pharomachrus mocinno) at nest hole, El Triunfo Biosphere Reserve, Sierra Madre de Chiapas, Mexico.

TOM MANGELSEN / Portrait of a male Resplendent quetzal (Pharomachrus mocinno) perched on a branch, El Triunfo Biosphere Reserve, Sierra Madre de Chiapas, Mexico.