Rock ptarmigans are circumpolar, meaning they are found in many places all around the North Pole. This includes countries such as Russia, Sweden, Canada, Iceland, Greenland, and other areas north of the Arctic Circle. In some instances they may be found further south. Japan is one such location.
Adult ptarmigans feed on leaves, flowers, berries, buds, twigs and other types of vegetation. Young ptarmigan chicks are fed insects in addition to vegetation.
Rock ptarmigans can be found in elevated, rocky, sloped areas of the tundra. Females and chicks prefer areas with brush to protect them from predators, while males prefer open, barren areas to assist them in locating predators and other ptarmigans.
They measure between 12 - 16 inches in length.
Rock ptarmigans may molt several times a year and change colors when they do so. During the summer months, they have a spotted brown color with males shedding their white winter plumage later than females. This allows the males to be spotted by females easily against the brown tundra, but also allows them to be seen by predators.
Females are extremely difficult to spot in the summer, even from close distances. In the winter both sexes shed their brown plumage for an almost pure white coat. Males have a red comb over their eyes.
Females will lay between 6 - 10 eggs and will then incubate them for about 3 weeks. The male will leave the female, eggs and nest at some point during the incubation period, and the female will complete the raising of the chicks on her own. The chicks will acquire feathers, also known as fledging, in about 10 - 12 days.