Rock Ptarmigan

The rock ptarmigan is a medium-sized game bird in the grouse family. It is known simply as the ptarmigan in the UK. Unlike many arctic inhabiting bird species, ptarmigan do not gain substantial mass to survive over winter. The rock ptarmigan is seasonally camouflaged; its feathers moult from white in winter to brown in spring or summer. The breeding male has greyish upper parts with white wings and under parts. In winter, its plumage becomes completely white except for the black outer tail feathers and eye line. It can be distinguished from the winter willow ptarmigan by habitat and markings, the rock ptarmigan prefers higher elevations and more barren habitat. It also has a slender bill and a black eye stripe, which is absent in the willow ptarmigan.