The rock ptarmigan is well adapted to harsh surroundings like the open tundra or barren and rocky slopes in the mountains. It spends most of its life on the ground at or above the treeline. The bird changes its colours between seasons to blend in with its surroundings. In winter it is pure white and in spring and summer it is brown. It has feathered legs and toes that help keeping them warm and to walk in the snow.
When nesting the male defends the territory but when the eggs are hatched they leave it to the female to care for the young. The chicks grow quickly and by autumn they are almost adult size and are able to fend for themselves.
The rock ptarmigan has a circumpolar distribution in northern and arctic regions, in addition to the Alps and the Pyrenees. It is the most northern, resident herbivorous bird in the world.
The habitat typical for rock ptarmigan is the tundra or alpine summits. Birds are rarely observed in areas of high shrubs or below the tree line. During winter they live in less snowy, windswept areas to take the food from the ground (mainly buds and twigs of species, including polar willow).
The main human-caused threats to the rock ptarmigan at a local scale is habitat degradation (e.g. as a result of development of tourist facilities) and over-hunting. The global population has aprox. 8 mln individuals.
The sub-species of rock ptarmigan is Svalbard rock ptarmigan.