Rock Ptarmigan

The hardy Rock Ptarmigan nests as far north as there is land in the world. This chunky grouse wears two kinds of camouflage: it’s nearly all-white in the snowy winter and mottled brown in the summer.

Male Rock Ptarmigan stay white until they’ve finished courting females, and then intentionally dirty their plumage to hide from predators until they have molted into a safer (but less dashing) brown plumage. Their feathered feet help them to walk on deep snow and to dig snow burrows and tunnels for refuge from severe cold. Cornell All About Birds