courtship rituals involve fast forward flight with rapidly-beating wings followed by an upward glide, tail fanned out. The male, at the peak of the display, belts out a rasping "ah-AAH-ah-AAAAH-a-a-a-a-a-a!", with the sung latter part coinciding with a gliding descent afterwards. The sound is often described as that of a stick being pulled rapidly across the slats of a picket fence. On the ground, male ptarmigans defend their space by calling and giving chase to other males. Physical conflicts between territorial males rarely occur, while confrontations between the former toward subordinate males are intensified. Other signals via fanning their tails, extended necks, lowered wings and circling a receptive female are also utilized. Distribution and habitat The rock ptarmigan is a sedentary species which breeds across Arctic and Subarctic Eurasia and North America (including Greenland) on rocky mountainsides and tundra. It is widespread in the Arctic Cordillera and is found in isolated populations in the mountains of Norway, Scotland, the Pyrenees, the Alps, Bulgaria, the Urals, the Pamir Mountains, the Altay Mountains, and Japan—where it occurs only in the Japanese Alps and on Mount Haku. Because of the remote habitat in which it lives, it has only a few predators—such as golden eagles—and it can be surprisingly approachable. It has been introduced to New Zealand, South Georgia, the Kerguelen Islands, and the Crozet Islands. The small population living on Franz Josef Land in the Russian High Arctic overwinters during the polar night and survives by feeding on rich vegetation on and underneath high cliffs where seabird colonies are located in summer. During the last ice age, the species was far more widespread in continental Europe. Ecology Feeding Food sources can vary tremendously depending on the region of their distribution. In Alaska, rock ptarmigans consume aspen buds, dwarf birch and willow buds and catkins as a staple winter diet. They transition their diets over to crowberries and lingonberry shrubs during the spring. The greatest variety in its diet occurs during early summer, when it feeds on willow leaves, as well as the leaves and flowers of Dryas and locoweed. It also feeds on berries, bistort seeds, and birch buds from late summer to autumn. Insects, larvae and snails are eaten by chicks. Breeding Apart from the red eye combs, male rock ptarmigans have no 'distinct' plumage (other than the black eye stripe) that are more typical for other grouse in temperate regions.