Dark-eyed Junco ("Slate-colored" race) (Junco hyemalis hyemalis)

The Sibley field guide describes 6 geographical populations of this common North American emberizid. In winter they are found at lower latitudes, and at lower altitudes, than in summer. All are characterized by a pinkish bill and by white outer tail feathers, which are especially conspicuous in flight. The "Slate-colored" subspecies (shown here) has the plainest overall plumage and seems to be the most common junco in the East.