Dolichonyx oryzivorus
Order Passeriformes
Family Icteridae
Subfamily Dolichonychinae
♂ Adult male.— Nape buffy-white; shoulders and lower back white; otherwise black.
♀ Adult female.— Upper parts brown, streaked; under parts yellowish-brown, unstreaked; line over eye and line through crown buffy.
♂ Male in August and Immature.— Similar to female, but yellower.
Nest, placed on the ground in some tuft of grass or weeds.
Eggs, white, blotched with brown.
The Bobolink is a common summer resident throughout New England and New York, wherever there is grass-land, though absent apparently from Cape Cod, and local in the vicinity of New York city. It arrives early in May, and stays till September. It breeds in mowing-land of grass or clover, and at the edges of grassy marshes. Here the males through May and June pour forth their rollicking song, either from the tops of the neighboring trees, or from some bending weed, or tuft of grass. Often they sing in the air, either gliding with curved wings or chasing each other furiously over the field. About the first week in July the young ones leave the nest, and now the song of the males ceases abruptly. If one approaches the grass where a young one is hiding, both parents hover near, uttering a chuck of alarm, flying from one perch to another, spreading the tail nervously. Towards the end of July the males begin to lose the black-and-white plumage; it is replaced by a dress similar to the female’s, but yellower. About this time old and young gather in large flocks, which roost each night in the long grass of some low meadow. As they pass to and fro they utter a mellow chink, which is one of their ordinary call-notes; this note may be heard at night in August and early September from migrant flocks.
The young birds and the males in autumn may be known by their unstreaked yellowish under parts, and by the buffy line over the eye; in spring the presence of the brightly marked males will often help one to identify the plain-colored females.
Hoffmann – A Guide to the Birds of New England and Eastern New York (1904)