Very similar to Reed Bunting, but smaller and more slender; also note finer bill, colder pale buffy-brown (instead of rufous) wing coverts, and less extensive streaking on the underparts. Breeding male has a black hood and bright white “moustache” stripe. Female and non-breeding birds are pale sandy brown with a pale but noticeable white “moustache.” Breeds in thickets and vegetation clusters in tundra and winters in reedbeds and tall grassy or brushy areas near water, where often associated with mixed-species flocks. Song is a series of wet buzzy “tsli” notes. “Chlip” calls distinctly sparrow-like.