WILLOW PTARMIGAN live in the colder parts of the northern hemisphere, often well beyond tree limits. They are children of the wide desolate tundras where the sun appears for only a few months each year. Males are monogamous and fight one another with unusual ferocity for the females' favor. In those inhospitable regions Nature intends that only the strongest shall survive — a rather unnecessary test when the severity of the climate is considered.
They are so pugnacious at this time that Nelson states they can be decoyed into gunshot by a ruf imitation of themselves.
The loud raucous challenge of males in spring, reaches its height between ten p. m. and two a. m. (which corresponds to dawn in more southern latitudes).
Food of insects, berries and seeds is plentiful in summer but in winter Ptarmigans feed entirely on terminal bush and tree buds.
Arctic regions from northern Alaska to central Greenland; south in winter to southern British provinces and rarely to northern United States.