
Species Identification:
The Acadian Flycatcher is a small song bird, 15 cm long and 12- 14 grams. They have an olive-green crown, back and tail with a pale whitish throat and breast. The most prominent feature of this bird is the bold white ring around the eye, and two white-ish horizontal bars on the wing. Their beak is short but has a wide base, allowing a big opening for snatching insects out of the air. Males give a distinct “peet-sa” call.
Diet:
The Arcadian Flycatcher mostly feeds on insects and insect larvae found on leaves and low vegetation, and they will often snatch insects in the air. Diet staples include bees, wasps, ants, moths, beetles, spiders, and flies.

Biology and Behaviour:
Males start to arrive in Ontario mid-May, and females arrive about a week later. They often return to the same breeding territory. The female builds a loose cup nest on a horizontal branch of a small tree like American Beech, Witch-hazel, Sugar Maple, Eastern Hemlock, or Eastern Flowering Dogwood. They lay 3 eggs on average, which are incubated by the female for two weeks. After hatching, the young are fed by both adults for another two weeks, and will stay close to the nest for a week after that. The male’s territorial “peet-sah” call is frequently heard, and both sexes call to each other with characteristic vocalizations. Fall migration begins from late July to early September. Nest predation is fairly common. Likely predators include raptors, snakes, small mammals, and Blue Jays

Similar Species:
There are 15 other Empidonax species in the Americas that look fairly similar. The Acadian Flycatcher is best distinguished by its “peet-sah” call.

Conservation and recovery strategies:
The Acadian Flycatcher is representative of a group of neotropical migrants that are vulnerable to shifts in forestry practices in Canada and the United States. It is considered a good indicator, as it is vulnerable to a range of habitat disturbances.
The provincial strategy involves identifying key areas to conserve, and to encourage the consideration of habitat needs in management planning. They also have plans to better survey populations, monitor threats, and expand Ecological Land Classification surveys. The province aims to maintain the current population level of 35 to 50 pairs.
Forestry practices that use selective logging that intentionally leaves large-diameter and older trees. Selective logging can also prevent forest fragmentation and risks of brood parasitism.
Additional Resources:
- Cornell Lab, Birds of North America profile.
- COSEWIC Assessment and Status Report, 2010.
- Ontario Recovery Strategy, 2016.

Sources:
COSEWIC. 2010. COSEWIC Assessment and Status Report on the Acadian Flycatcher (Empidonax virescens) in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. X + 38 pp.
Environment Canada. 2012. Recovery strategy for the Acadian Flycatcher (Empidonax virescens) and the Hooded Warbler (Wilsonia citrina) in Canada. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa, Ontario. viii + 32 pp.
Ontario Ministry of Natural Resources and Forestry. 2016. Recovery Strategy for the Acadian Flycatcher (Empidonax virescens) in Ontario. Ontario Recovery Strategy Series. Prepared by the Ontario Ministry of Natural Resources and Forestry, Peterborough, Ontario. v + 5 pp. + Appendix.