One of the 2 species of Western Flycatchers. A small flycatcher, with length 14 to 17 cm and mass 9 to 12 g. The Cordilleran Flycatcher is slightly larger and heavier than its counterpart, the Pacific-slope Flycatcher. Western Flycatchers are pale, dull yellowish with teardrop- or almond-shaped eye-ring, olive-green upperparts, dull-brownish flight feathers and wing-coverts with dingy yellowish wing-bars, dull-yellowish underparts, relatively long tail and short wing, gray leg color, and broad bill with yellow-orange to pinkish lower mandible. Tend to appear relatively large-headed, with rather prominent short peak to rear crown. The Cordilleran Flycatcher is distinguished by its 2-part call (Lowther 2000).
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see Marks et al. 2016, Birds of Montana.
Western Hemisphere Range
"Coolness, shade, and nest sites" are requisites, and this species, from Alberta to northern Mexico, "invariably associated with water courses, and thus openings, in the timber" (Johnson 1980, Lowther 2000).
Feeds almost exclusively on insects caught in the air or gleaned from foliage of trees and shrubs (Lowther 2000).
Has been know to nest in rocky outcroppings near water, in natural nest cavities in live trees (quaking aspen, Douglas fir), tree stumps, and about mountain cabins. Eggs are subelliptical to elliptical in shape. Dull white or creamy white and marked. Clutch size usually four. Eggs have been reported in July (Davis 1961), but the dates are probably similar to those reported for Colorado: June 3 to July 23 (Johnsgard 1986).