The chestnut-backed chickadee (Poecile rufescens, formerly Parus rufescens) is a small passerine bird in the tit family, Paridae.

It is found in the Pacific Northwest of the United States and western Canada, from southern Alaska to southwestern California. It is a permanent resident within its range, with some seasonal movements as feeding flocks move short distances in search of food. They usually move to lower elevations in the same area upon onset of winter and move back up to higher elevations in late summer.

It is a small chickadee, 11.5–12.5 cm (4.5–4.9 in) long with a weight of 8.5–12.6 g (0.30–0.44 oz). The head is dark blackish-brown with white cheeks, the mantle is bright rufous-brown, the wing feathers are dark gray with paler fringes. The underparts are white to pale grayish-white, with rufous or pale gray flanks. It is often considered the most handsome of all chickadees. They often move through the forest in mixed feeding flocks, and are often seen in large groups with Bushtits and warblers.

Ref: Chestnut Backed Chickadee Information