A ptarmigan is a plump bird that lives in mountainous places.
Its scientific name is Lagopus muta, and its range extends across northern regions of Europe, Asia, and North America.
It is remarkable for its plumage, which provides good camouflage in all seasons. To see an image of the winter plumage, which makes the bird inconspicuous against the snow, visit:
http://fwp.mt.gov/mtoutdoors/HTML/articles/portraits/ptarmigan.htm
For the summer plumage:
http://www.statesymbolsusa.org/Alaska/bird_willow_ptarmigan.html
and for the transitional (between-seasons) appearance:
http://en.wikipedia.org/wiki/Ptarmigan