“The nesting song may be heard commonly on the breeding grounds. I have several records from the Adirondacks. This song is in three or four parts, each part of three or four notes, and a little lower in pitch than the preceeding part. Two-note phrases are not commonly heard in the nesting song.”
Francis H. Allen’s rendering of the song is not very different from the first one of Mr. Saunders', though he noted some variation, and mentions in his notes an aberrant song, which “doubled the common song, which in this case had a first part consisting of only a single phrase, thus; chip-ee-(trill) chip-ee-(trill).”
Field marks.—The gray head, white eye ring, olive-green back, bright yellow under parts, and the absence of wing bars, with no white in the tail, are the distinguishing marks of the eastern Nashville warbler. The Connecticut warbler has a white eye ring but it has a gray throat, whereas the Nashville is bright yellow from chin to abdomen. The chestnut crown patch is not very conspicuous in the male and is less so, or entirely lacking, in the female; the female is duller yellow below and browner above than the male.
Enemies.—Like other ground-nesting birds, this warbler has the usual four-footed enemies to contend with, but its nest is quite well hidden. Perhaps its worst bird enemy is the cowbird, although Friedmann (1934) listed it as an uncommon victim of this parasite and had only six records of it, the nests containing from one to two eggs of the cowbird.
Fall.—As soon as the molting season is over and the young birds are freshly clad in their winter dress the migration begins in Massachusetts. This takes place in August, and the last stragglers may be seen passing through in early October.
In Ohio, according to Mr. Trautman (1940), the first migrants are seen about the first of September, the peak of the migration coming during the latter half of that month when from 10 to 100 could be found in a day, and after the 10th of October only an occasional bird remains. He writes: “As with many other transient warblers the southward migration of the Nashville Warbler covered a greater period of time than did the spring movement, which usually lasted less than 30 days, whereas the fall movement generally extended more than 45 days. * * * In spring the species frequented the upper half of large trees and was more numerous in tall trees of woodlands than it was in smaller groups or rows of tall trees. In fall the species tended to inhabit the middle section of large trees, and it also resorted to the taller bushes and saplings, especially the larger hawthorn trees.”
The fall migration route is apparently a reversal of the spring route southwestward into Mexico and Central America where it spends the winter.
Winter.—The Nashville warbler is evidently very common in winter in certain parts of Mexico, for Dr. C. William Beebe (1905) says: “At times there were twenty and thirty in sight at once near our camp in the Colima lowlands.” These may have been the western race.
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