White-throated Sparrow

White-throated Sparrow is an uncommon winter visitor to Sonoma County, migrating from northern breeding grounds mostly in Canada. White-throated Sparrow is the least common of the three sparrows of the genus Zonotrichia that regularly move into the county over the winter from colder climates in the north, the others being Golden-crowned Sparrow (Zonotrichia atricapilla) and White-crowned Sparrow (Zonotrichia leucophrys), although there is a non-migrating coastal population of White-crowned Sparrow as well. There are two White-throated Sparrow color morphs, usually referred to as "white-striped" and "tan-striped," referring to the color of the pale, broad lateral head stripes just above the eye. Both forms are illustrated on this page. All immature birds are tan-striped. White-striped birds acquire the white with adult plumage. Typically seen in woodland undergrowth, but also in suburban settings near woods. Visits feeders. Often mixes with flocks of White-crowned and Golden-crowned sparrows.

True to its name, White-throated Sparrow has a prominent white patch at the throat but also a strikingly striped head. Note the distinctive dark stripe mostly behind the eye, and patches of yellow at the lores (the forward part of the tan or white lateral stripes). The central stripe on top of the head is usually white but yellowish in young birds. Otherwise, mostly pale grey upper breast (smudged grey in first-year birds) with a vague dark spot in the middle and with tweedy brown upperparts and attenuated white wingbars, similar to the other Zonotrichia sparrows. Lower belly and vent are white. The bill is usually darkish, the legs usually pink. The tan-striped form tends to have more of the darker upper breast grey than the white-striped form. Juveniles resemble the tan-striped form but with well-defined streaking on the breast and paler areas on the head that make the auricular patch stand out. Fine, dark stripes that divide the white throat patch into three sections (or a suggestion of them), although somewhat variable, are present in both juveniles and adults.

Selected county sightings: Sonoma Developmental Center (December 30, 2015, Colin Talcroft); Arroyo Sierra Dr. (Feb 8, 2013, Colin Talcroft); Arroyo Sierra Dr. (12/16, 2012, CBC group); Strawberry School Park (December 21, 2011); Strawberry School Park (December 18, 2011), Ellis Creek Water Treatment Facility (November 5, 2011); Wright's Beach (October 16, 2011, Lisa Hug); Ellis Creek Water Treatment Facility (January 18, 2011, Bob Dyer); Arroyo Sierra Dr. (October 26, 2010); Melita Rd. (April 27, 2010); Spring Lake (October 17, 2009)