6-6 1/2" (15-17 cm). Red head and red and brown streaked back and wings. Light buff below with no streaking. Females are gray-brown above with white streaking and white below with gray-brown streaking.
Similar Species- Purple Finch, House Finch
Warbling song ending in a 2-3 note ascending scale. Calls a tcher-werp.
Breeds from southern interior British Columbia, extreme southwestern Alberta, Montana, and northern Wyoming, south to portions of California, southern Nevada, northern Arizona and northern New Mexico. Winters mainly from southern British Columbia, northwestern Montana, and eastern Wyoming, south to northern Baja California, southern Arizona, and central Mexico.
Found in open, montane coniferous forests at higher elevations. During migration and in winter, also found in deciduous woodlands, second growth, scrub, brushy areas, partly-open situations with scattered trees, and occasionally in suburbs near mountains. Idaho study found Cassin's Finches responded positively in number to diameter-cut logging.
Eats seeds and buds of plants, insects, and berries.
Forages on ground, or takes food from foliage. Builds cup-shaped nest in tree, frequently near end of large limb. Male defends zone around female during breeding period; female is more attached to particular site than is male. Individuals are usually seen in flocks, except during nesting season. Often seen in association with crossbills and Evening Grosbeaks.
Female incubates 3-6 eggs (usually 4-5), for about 12-14 days. Young are tended by both adults, and first breed as yearlings in some areas, and at 2 yr in other areas.
Medin, D.E. 1985. Breeding bird responses to diameter-cut logging in west-central Idaho. USDA Forest Service Inter. Res. Sta. Res. Paper INT-355, Boise. 12pp.