Breeding Bird Atlas 1 Species Accounts
Acadian Flycatcher
Empidonax virescens
Egg Dates
Number of Broods

Spring arrivals can be found during the third week in May, both in southeastern and western Massachusetts. Migration continues into June, and many singing males seem to disappear after failing to attract mates. Actual breeding remains very localized in dense, well-watered woodlands, especially along small streams, and in the west is strongly associated with Eastern Hemlocks. The fact that there is much appropriate habitat in the western hills and that this area is close to the base population in Connecticut accounts for the breeding population that has become established there in the years following the Atlas period. The nesting birds in eastern Massachusetts have all been in deciduous woods, with Red Maple predominating; and no recurring pairs at any one site have been identified in that region.
The birds seem to prefer steep hillsides or ravines, but the nest itself is built near or over the slow-moving portions of the stream itself. There, in the shade of the lower branches of the larger trees, the bird goes about its fly-catching business, the male sneezing out his short emphatic song through most of the summer. The song is basically a two-syllable peet-seet, the first part rising and slightly drawn out and the second louder, short, and sharply falling. The only variety seems to be in the degree of harshness in the notes, with the first syllable tending generally to be somewhat less harsh. It resembles the single, almost burry-sounding phrases in one of the Red-eyed Vireo’s songs. The call note is a nondescript peep. On the breeding grounds, the bird also utters a fast series of soft melodious notes, almost a trill, fluttering its wings as it does so, much like a young bird begging for food. This sound is also occasionally heard on migration.
The hanging nest of grasses, rootlets, or moss is not well built, being rather loose with a thin bottom, always in the outer fork of a lower horizontal or drooping branch, usually 8 to 15 feet above the ground or water. Often, streamers of vegetation are attached to and hang below the nest for a foot or more. All of the nests found in western Massachusetts have been in Eastern Hemlocks. The 1977 Middleboro nest was built 10 feet above the ground on a branch 7 feet from the trunk of a Black Gum. It was partially built on June 30 (Petersen, BOEM). Two to four eggs are laid, and the clutch sizes for 2 Massachusetts nests were three eggs each (EHF, BOEM). Incubation lasts almost two weeks, with a single brood the rule. If a cowbird disturbs the nest before the eggs are laid, the birds may build again. Acadian Flycatchers have been observed incubating on June 20 in Royalston (TC), June 28 in Granville, and July 8 in Middleboro (Petersen, BOEM).
Data on nestlings and fledglings in Massachusetts is lacking. Presumably, adults and young remain together for two or more weeks after fledging, but the birds are very quiet and inconspicuous at this time. The southward departure begins in early August and is completed in a month, but few individuals are identified at this time due to the similarity to other Empidonax species. Acadian Flycatchers winter in humid lowland forests from Nicaragua south to northern South America.
Map Legend and Data Summary

