The sooty fox sparrow contains the darkest-colored taxa in the genus Passerella. It is currently classified as a "subspecies group" within the fox sparrow pending wider-spread acceptance of species status. It has long been suspected to be a separate evolutionary lineage due to morphological distinctness, and this is confirmed by analysis of mtDNA sequence and haplotype data. This group appears to be most closely related to the thick-billed and/or slate-colored fox sparrows.
Region
Pacific Coast of North America
Typical Environment
Breeding populations occur from the Aleutian Islands and coastal Alaska through British Columbia, favoring dense coastal conifer forests, alder–willow thickets, and maritime shrublands. In winter, birds move south along the Pacific slope through Washington, Oregon, and California, reaching into northern Baja California. They prefer brushy edges, riparian tangles, and overgrown gardens where there is ample leaf litter. Local populations on outer islands may be more sedentary.
Altitude Range
Sea level to 2000 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
The sooty fox sparrow is the darkest member of the fox sparrow complex, with mtDNA and morphology supporting its treatment as a distinct species by some authorities. It breeds in dense coastal thickets from Alaska southward and winters along the Pacific Coast. Like many ground-foraging sparrows, it performs a rapid double-scratch in leaf litter to uncover seeds and insects.
Temperament
shy and skulking
Flight Pattern
short rapid wingbeats between cover
Social Behavior
Typically solitary or in loose small groups outside the breeding season. Monogamous pairs defend dense, shrubby territories in the breeding period. Nests are cups placed low in shrubs or on the ground; both adults feed the young.
Migratory Pattern
Partial migrant
Song Description
The song is a rich, clear series of melodious whistles and trills, reminiscent of a small thrush. Calls include a sharp smack or chak and thin seep notes given from cover.
Plumage
Uniform sooty-brown to chocolate-brown upperparts with heavy, blurry dark spotting on the breast that often coalesces into a central blot; underparts otherwise whitish to grayish. Minimal contrast between head and back; wings and tail lack obvious wingbars. Overall appearance is darker and more smudged than other fox sparrow groups.
Diet
Feeds on seeds of grasses and forbs, small fruits and berries, and a wide range of insects and other invertebrates. In the breeding season, it takes more animal prey such as beetles, caterpillars, and spiders to provision nestlings. In winter, it relies heavily on seeds and fallen berries and will visit backyard feeding areas.
Preferred Environment
Forages on the ground in dense thickets, forest edges, coastal scrub, and riparian understory with abundant leaf litter. Often feeds under shrubs or at the bases of trees, frequently using a two-footed double-scratch to uncover hidden food.
