This section is from "The American Cyclopaedia", by George Ripley And Charles A. Dana. Also available from Amazon: The New American Cyclopędia. 16 volumes complete..
Bobolink, Or Rice Bunting (Emberiza Oryzi-Vora, Linn.; dolichonyx oryzivorus, Swains.), the rice bird or ortolan of Georgia and Carolina, the reed bird of the middle states, and the bobolink of the north and northwest, migratory through the whole length of the North American continent and islands, from Labrador to Mexico and the Antilles. The plumage of the male bird is entirely different at various seasons. The bobolink winters mainly in the western isles, and not in the tropical parts of this continent. Early in spring the birds begin to appear in the southern states in small parties, the females often preceding the males, tarrying only a few days, seen only in small companies, and for the most part making their journeyings by night. In the first days of May they appear in Massachusetts, gayly clad in full dress, and in full song, and at this period are neither gregarious nor predatory, though on their northern voyage they damage the crops of young grain. The length of the bobolink is about 7 1/2 inches; the male, in his spring dress, has the upper part of the head, shoulders, wings, tail, and the whole of the under plumage black; lower part of the back bluish white; scapulars, rump, and tail coverts white; there is a large patch of brownish yellow on the nape and back of the neck; bill bluish black, which in the female, young male, and adult, after the month of June, is pale flesh color; the feathers of the tail formed like a woodpecker's; legs brown.
The female, whose plumage the adult male assumes after the breeding season, has the back streaked with brownish black; the whole lower parts of a dull yellow. The young birds have the dress of the female. During the breeding season they frequent cool, grassy meadows, which they render vocal with their quick, merry song, the male singing to the female while she is sitting. "He chants out," says Wilson, "such a jingling medley of short variable notes, uttered with such seeming confusion and rapidity, and continued for a considerable time, that it appears as if half a dozen birds of different kinds were singing all together. Many of the tones are in themselves charming, but they succeed each other so rapidly that the ear can hardly separate them. Nevertheless the general effect is good, and when 10 or 12 are all singing in the same tree, the concert is singularly pleasing." The female makes an inartificial nest of withered grass, in some depressed place in the meadows, and lays five or six eggs of purplish white, blotched all over with purplish stains, and spotted with brown at the larger end.
During April, May, and June the males are constantly singing, and they neither congregate nor damage any crops; but toward the end of June they become silent, and gradually assume the coloring of the females, so that by the beginning of August the change is complete. They now assemble in vast flocks, mute with the exception of a short, sharp chirrup, and do some mischief to the latest crops of oats and barley; chiefly, however, they congregate in throngs along the river beds and lake margins, wherever the wild rice (zizania aquatica) grows abundantly. Along the Delaware and Schuylkill, as also on the borders of the New Jersey and many of the Virginia streams, they are much pursued by sportsmen. As the cool nights draw on, late in September and early in October, they quit their northern summering places for the southern rice fields, which they at times glean so completely that it is useless to attempt to gather the grain. Here they become so fat and sluggish that they can scarcely fly, and when shot are frequently known to burst open on striking the ground.
Before the rice crop is fully gathered, they have already made their appearance in Cuba and Jamaica, where they repeat the same ravages on the seeds of the guinea grass (sorghum), and grow so fat that they receive the name of "butter birds."
Bobolink (Dolichonyx oryzivorus).