The head, back, wings, and tail are a bright sky blue. Males are light blue from the chin to the belly, and grayish-white on the belly and undertail coverts. Females have brownish-gray upper parts. The wings, rump, and tail are a pale or light blue. Females sometimes have a pale reddish throat and breast, but more commonly, the throat and breast are gray brown.
Juveniles look like adult females, but they are darker and less colorful.
Their breasts and sides are streaked with brown. This species song is a deep chur or phew. A very subdued warble. Distribution and Breeding Habitat Mountain Bluebirds are found in the western parts of Canada and the United States. They are found at elevations above 7,000 feet, and they nest in open areas such as meadows, hayfields, grain fields, savannas, prairies, clear cuts, and the edges of coniferous and deciduous forests.