Bell’s Sparrows are dark brown above with a dark gray head, white underparts and a dark spot in the middle of the breast. The dark face has a contrasting white eyering, a white spot before the eye, and strong white and dark stripes bordering the throat. The tail is dark. Juveniles are more uniformly brown, lack the gray head, and are streaky beneath.
They are fairly inconspicuous birds that spend much of their time on the ground or concealed in shrubs, except during early summer when males sing from prominent perches. When crossing open areas they tend to run along the ground with the tail held high.
Bell’s Sparrows live in shrubby areas of California and Baja California, including coastal sagebrush and chaparral, as well as the Mojave Desert and California’s San Clemente Island. Many are year-round residents, but some migrate to southern California and western Arizona for winter, where they mix with the very similar Sagebrush Sparrow and other species in open, dry habitats.
Bell’s Sparrow consists of four subspecies with somewhat distinct plumages. Two are noticeably dark gray on the head with nearly entirely dark tails and unstreaked backs: these are A. b. belli, which occurs mainly in coastal California sage; and A. b. clementeae, a federally threatened subspecies that occurs only on San Clemente Island. There are also two lighter forms: A. b. canescens, of the Mojave desert region, which closely resembles Sagebrush Sparrow; and A. b. cinerea, of Baja California, which has buffier face markings than the other three subspecies.