Often called "Buff-bellied Pipit" in Old World literature but in winter they lack the buff-colored underparts which this species gets in the breeding season. At that time the underparts may be largely unstreaked. Birds migrating through and wintering in California are presumed to be the subspecies A. r. pacificus, which averages dingier overall and less patterned with blurrier streaks below. Alstrm & Mild merged pacificus as a junior synonym of nominate. However pacificus is still recognized as valid by Clements/eBird and H&M4 but not by IOC.
