A small to medium-sized bird of montane forest middle story and subalpine scrub. Off-white underparts, brown back, gray head, white throat and a brown wash on the sides of the chest. Very similar to Island Whistler but does not co-occur. Mountain Mouse-Warbler is similarly colored but smaller and restricted to the understory or ground. Song, a forceful series of upslurred “whip!” and downslurred “chew!” notes.