A plump, large-headed, brownish bird with an extremely long tail. Plain overall with no distinctive plumage features; look for pale eye and stubby bill. Difficult to see, but often heard giving an accelerating series of hard chip notes. Usually solitary or in pairs. Skulks through low, dense vegetation, especially chaparral. Restricted to the Pacific coast of North America, from Oregon to northern Baja. Not closely related to any other species in the Western Hemisphere. Might be confused with Bushtit, but larger and much different behavior and vocalizations.