Willow ptarmigan in favourable seasons, many juveniles may survive and the population of willow ptarmigan is prone to wide fluctuations in size. By September, families begin to form flocks. The females and young migrate to lower altitudes and may overwinter from their breeding grounds in wooded valleys and hilly country. The males also congregate in small groups but do not usually travel as far as the females. The willow ptarmigan was adopted as the state bird of Alaska in 1955. Widespread and not uncommon in its remote habitat, the willow ptarmigan is classified as a species of "Least Concern" by the IUCN.
Ptarmigan Pass (Sawatch Range) the Eagle River Valley near Red Cliff. Ptarmigan Pass (Sawatch Range) Ptarmigan Pass (elevation 11,765 ft) is a high mountain pass in the Rocky Mountains of central Colorado in the United States. It is located on the crest of the northern end of the Sawatch Range, along the border of Eagle and Summit counties, south of Vail Pass. The pass is traversed by a jeep trail that is passable by four-wheel drive vehicles and on foot. 2WD vehicles will only make it to the summit from the west; the east side is rocky and boggy at times. The trail connects