The bobolink (Dolichonyx oryzivorus) is a small New World blackbird and the only member of the genus Dolichonyx.
Adults are 16–18 cm (6.3–7.1 in) long with short finch-like bills. They weigh about 1 oz (28 g). Adult males are mostly black with creamy napes and white scapulars, lower backs, and rumps. Adult females are mostly light brown, although their coloring includes black streaks on the back and flanks, and dark stripes on the head; their wings and tails are darker. The collective name for a group of bobolinks is a chain.
The bobolink breeds in the summer in North America across much of southern Canada and the northern United States. It migrates long distances, wintering in southern South America in Argentina, Bolivia, Brazil and Paraguay. source