Measurements
Both Sexes
- Length
- 5.9 in
15 cm - Wingspan
- 9.1 in
23 cm - Weight
- 0.4–0.5 oz
11–14 g
Cool Facts
- Curiously, no information exists on the ability of the Acadian Flycatcher to walk or hop. It is an excellent flier, though, extremely maneuverable and able to hover and even fly backward. It has been observed bathing not by standing in water, but rather by diving into water from above, hitting the water with its chest, and then returning to a perch to preen and shake.
- The male defends his territory with a characteristic "peet-sah" song. The female may use the same call in stressful situations, such as when disturbed from the nest or right after being released from a mist net.
- The Acadian Flycatcher is a common host to the brood-parasitic Brown-headed Cowbird, which lays its eggs in other birds' nests. Nests are parasitized more in small woodlots than in large tracts of forest. The frequency of parasitism is lower for the flycatcher than for other bird species in the same forests. From the cowbird's perspective the Acadian Flycatcher does not seem to be a particularly good host: only 16% of cowbird young in Acadian Flycatcher nests fledged successfully.
Habitat

Forest
- Breeds in mature forest, especially deciduous woods, along streams, in ravines, and in swamps.
- Winters in lowland tropical forest and second growth.
Food

Insects
Insects, insect larvae, and other arthropods.
Nesting
Nesting Facts
- Clutch Size
- 1–4 eggs
- Egg Description
- Creamy to buffy white with some small brownish spots at larger end.
- Condition at Hatching
- Helpless with some white down.
Nest Description
Nest a shallow, thin cup of fine materials held together with spider and insect silk, usually dangling streamers of material on silk below nest. Slung hammock-like in fork of small branch in tree, usually over water.
Nest Placement

Tree
Behavior

Flycatching
Captures insects primarily by snatching them from leaves, especially from the undersides. Also hovers to glean insects and catches some in flight. Occasionally forages on ground.
Conservation

Least Concern
Populations nationwide appear to be stable, but may be declining in Midwest. Considered area-sensitive, showing a negative impact of forest fragmentation. Vulnerable to loss of wintering habitat.
Credits
- Whitehead, D. R., and T. Taylor. 2002. Acadian Flycatcher (Empidonax virescens). In The Birds of North America, No. 614 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.