Acadian Flycatchers use relatively undisturbed mature forest both on their breeding and wintering grounds. They often use riparian habitats, such as streams, wooded ravines, and river bottoms. They are sensitive to forest fragmentation and are more likely to occur in larger woodlots. This association with large tracts of undisturbed mature forests is also seen in their wintering range, where Acadian Flycatchers occur in understory thickets in both second-growth and primary tropical forest. On migration they sometimes stop over in more open wooded habitats.Back to top
Acadian Flycatchers eats mostly insects and insect larvae, which they usually take from the undersides of leaves during short sallies from an open perch in the middle levels of the forest. They also hawk insects from the air.Back to top
Acadian Flycatchers place their nests in a horizontal fork near the end of a slightly drooping branch of a small tree or shrub, typically between 10 and 30 meters off the ground.
Acadian Flycatcher nests are small hammocks made primarily of spiderwebs or cocoon silk interwoven with fine strips of bark, twigs, and understory grasses. Nests often have distinctive streamers hanging below the nest itself, made of plant fibers and fine twigs.
|Clutch Size:||2-3 eggs|
|Number of Broods:||1-2 broods|
|Egg Length:||0.6-0.8 in (1.6-2 cm)|
|Egg Width:||0.5-0.6 in (1.2-1.5 cm)|
|Incubation Period:||13-15 days|
|Nestling Period:||12-18 days|
|Egg Description:||Creamy to buffy white with some small brownish spots at larger end.|
|Condition at Hatching:||Helpless with some white down.|
Acadian Flycatchers perch quietly in the forest midstory, hawking insects from the undersides of leaves during short sally flights out and back from exposed perches. Males on their breeding territories sing a short, explosive song from conspicuous perches. They sit on dead branches more often than on live ones. They sing primarily in the early morning, decreasing in frequency throughout the day. Female Acadian Flycatchers inspect potential nest sites on male territories, and upon choosing a mate begin building the nest. Pairs are mostly monogamous and territorial, chasing away other males intruding upon the territory. Acadian Flycatchers fly to Central and South America for winter, and often return to the same winter territories year after year, as they do with their breeding territories.Back to top
Acadian Flycatcher populations remained roughly stable between 1966 and 2015, according to the North American Breeding Bird Survey. Partners in Flight estimates a global population of 5.2 million, and rates the species an 11 out of 20 on the Continental Concern Score, indicating a species of low conservation concern. Land managers assign Acadian Flycatchers a relatively high priority for management and monitoring, as this common species is an indicator of relatively mature forest interiors. The biggest threat to Acadian Flycatchers is the loss and, especially, the fragmentation of deciduous forest habitat. Forest fragmentation results in lower reproductive success and an increased rate of brood parasitism by Brown-headed Cowbirds. The Acadian Flycatcher requires mature forest on its wintering grounds as well, and is vulnerable to continued deforestation in the Neotropics.Back to top
Allen, Michael C., Megan M. Napoli, James Sheehan, Terry L. Master, Peter Pyle, Donald R. Whitehead and Terry Taylor. (2017). Acadian Flycatcher (Empidonax virescens), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A. and A. S. Love. (2019). Longevity records of North American birds. Version 1019 Patuxent Wildlife Research Center, Bird Banding Laboratory 2019.
Partners in Flight (2017). Avian Conservation Assessment Database. 2017.
Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski, K. L. Pardieck, J. E. Fallon, and W. A. Link (2017). The North American Breeding Bird Survey, Results and Analysis 1966–2015. Version 2.07.2017. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
Sauer, J. R., J. E. Hines, J. E. Fallon, K. L. Pardieck, Jr. Ziolkowski, D. J. and W. A. Link. The North American Breeding Bird Survey, results and analysis 1966-2013 (Version 1.30.15). USGS Patuxtent Wildlife Research Center (2014b). Available from http://www.mbr-pwrc.usgs.gov/bbs/.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.