Montana Field Guide

Medium-sized song bird. Plumage is characterized by white outer tail-feathers that flash when the bird takes flight and by a gray or blackish "hood" (head, nape, throat) and dark back that contrast with its whitish breast and belly. Exhibits marked geographic variation in plumage coloration and moderate variation in size with intergradations between the 5 distinctive groups. Identification of most groups is well covered by Howell and Webb (1995), Rising (1996), Dickinson (1999), and Sibley (2000), (Nolan, Ketterson, et al. The Birds of North America, No. 716, 2002).

The Bozeman migration for the Oregon form is from March 25 to May 10 and September 6 to November 5. For the slate color form dates are from April 2 to May and October 3 to November 15.

Occurs across the continent from northern Alaska south to northern Mexico. Conspicuous ground-foraging flocks are often found in suburbs (especially at feeders), at edges of parks and similar landscaped areas, around farms, and along rural roadsides and stream edges (Nolan, Ketterson, et al. 2002).

Seeds and arthropods; occasionally fruit and waste grain in agricultural fields. Most food obtained from ground and leaf litter (Nolan, Ketterson, et al. 2002).

Territory sizes for the Oregon form of 1.7 to 2.6 acres in Douglas fir and lodgepole pine in western Montana have been recorded.

Nest site highly variable. Most often in small cavity on sloping bank or rock face, under protruding rock, among roots (especially on vertical surface of root ball of large trees topple by wind), and in sloping road cut (especially if overhung by grass or other vegetation). Eggs are elliptical, white, gray, pale bluish white, or pale-greenish white in color. Clutch size most often 4 eggs, 5 and 3 not uncommon, (Nolan, Ketterson, et al. 2002). Near Fortine, egg dates range from May 1 to August 3. Statewide, nesting is from mid-April to August.