Since the American Ornithologists’ Union (1983) considered the White Wagtail (Motacilla alba) and Black-backed Wagtail (M. lugens) separate species, interest in their field identification in North America has grown. The White Wagtail breeds across Eurasia to western Alaska, while the Black-backed Wagtail breeds primarily in the Kamchatka Peninsula; the two are sympatric along the Bering Sea coast north of the Kamchatka Peninsula (Morlan 1981, A.O.U. 1983). The Siberian (and Alaskan) subspecies of the White Wagtail is M. a. ocularis, which, together with lugens, differs from other forms of White Wagtail in its black eyestripe; both forms winter in southeast Asia.