About the White-Crowned Sparrow
One of the most common winter sparrows, the white-crowned typically occurs in flocks, which may involve more than 100 birds. They feed in short grass or open areas adjacent to woodlands, hedgerows, or brush piles. They may pop out in response to pishing and raise their crown feathers when agitated. Polytypic. Length 7".
For bill color, see sidebar below; whitish throat; brownish upperparts; mostly pale gray underparts. Adult: black-and-white striped crown. Immature: tan and brownish head stripes. Juvenile: Brown and buff head; streaked underparts.
The white-crowned sparrow is divided into 3 well-defined subspecies groups: "dark-lored" (Rocky Mountain oriantha and eastern leucophrys), "pacific" (northern pugetensis and southern nuttalli), and "Gambel's" (western gambelli). Individual subspecies are often not identifiable in the field. The region around the lores gives the best first clue. The median crown stripe meets the eye line at the base of the maxilla in the "dark-lored" birds; the supercilium is pinched off and the supraloral region is black. In "pacific" and "Gambel's," the white supercilium meets the gray lores and the supercilium is not pinched off. Judge the bill color, carefully, too: yellow in "pacific," orange in "Gambel's" and pink in "dark-lored." "Pacific" birds often show a prominent malar stripe, rare in the others. Note as well that the primary extension is comparatively short in "pacific," longest in "Gambel's", and intermediate to longish in "dark-lored." "Pacific" lacks gray striping on its back, showing only dark brown and tan; gray striping is fairly prominent on the back of "Gambel's" and "dark-lored." "Pacific" also has more brownish coloration to its breast and flanks. First-winter birds show a distinctive difference that can be very hard to spot in the field: the first-winter "pacific" has a small patch of yellow feathers right at the bend of its wing; on "dark-lored" and "Gambel's," this patch is white.
The white-throated sparrow has a dark bill, prominent white throat, and yellow supraloral. Immature similar to immature golden-crowned, but note the latter’s dark gray bill, indistinct head pattern, and dingy underparts.
Call: loud, metallic pink. Flocking birds give a husky chatter. Flight note: sharp tseep. Song: one or more thin, whistled notes followed by a variable series of notes.
Status and Distribution
Common in the West, uncommon in East, rare in the Southeast. Winters south to central Mexico. Breeding: clumps of bushes or stunted trees on taiga and tundra; coastal scrub, chaparral for “Pacific” group birds. Winter: hedgerows, desert scrub, brushy areas, wood edges, and feeders. Migration: spring mid-March–mid-May, peaking early to mid-April; fall early September–mid-November, peaking mid-October. Vagrant: Europe and Asia.
—From the National Geographic book Complete Birds of North America, 2006