Willow Ptarmigan (Lagopus lagopus), Katmai National Park and Preserve, Alaska, United States of America, North America

An adult female willow ptarmigan (Lagopus lagopus) in summer plumage on the Snaefellsnes Peninsula, Iceland, Polar Regions

An adult female willow ptarmigan (Lagopus lagopus) in the shrubs in Denali National Park, Alaska, United States of America, North America

Female willow ptarmigan (Lagopus lagopus), Denali National Park and Preserve, Alaska, United States of America, North America

Willow Ptarmigan (Lagopus lagopus), Katmai National Park and Preserve, Alaska, United States of America, North America

Willow Ptarmigan (Lagopus lagopus)

Willow ptarmigan (Lagopus lagopus), summer plumage, Varanger, Norway, Europe

Close-Up Of Male Willow Ptarmigan Changing From Winter To Breeding Plumage Near Savage River, Denali National Park & Preserve, Interior Alaska, Spring

Close-up portrait of a male willow ptarmigan (Lagopus lagopus) showing early breeding colors in its neck and eye combs, surveying its high-country territory in Southcentral Alaska's Chugach Mountains on an April day. The head and neck will become completely chocolate-brown as the bird's breeding colors develop, Alaska, United States of America

Willow Ptarmigan (Lagopus Lagopus) In Plumage Transition From Brown Summer Color To White Winter Color

Willow Ptarmigan male (Lagopus lagopus) turning into his summer colours from his white winter's coat, Denali National Park and Preserve; Alaska, United States of America

Willow ptarmigan (Lagopus lagopus) in full-white winter plumage watches for danger on a bright February day, Anchorage, Alaska, United States of America

Close-up portrait of a Willow ptarmigan (Lagopus lagopus) in full-white winter plumage watching for danger on a bright February day, Anchorage, Alaska, United States of America

Willow Ptarmigans (Lagopus lagopus) standing in snow with white winter plumage in Arctic Valley, South-central Alaska, Alaska, United States of America

Willow Ptarmigan (Lagopus Lagopus), Denali National Park And Preserve, Alaska, Usa

Willow Ptarmigan (Lagopus Lagopus), Denali National Park And Preserve, Alaska, Usa

Willow ptarmigan (Lagopus lagopus), adult male in flight over the tundra in Varanger, Norway.

Willow ptarrmigan (Lagopus lagopus) in winter plumage in the snow, James Bay, James Bay, Province of Quebec, Canada