The Yellow-bellied Flycatcher (Empidonax flaviventris) is a small insect-eating bird of the tyrant flycatcher family.
Adults have greenish upperparts and yellowish underparts (especially on the throat), with a dusky wash on the chest. They have a white or yellow eye ring that lacks the teardrop projection of Pacific-slope (E. difficilis) or Cordilleran (E. occidentalis) Flycatchers, white or yellowish wing bars that contrast strongly against the black wings, a broad, flat bill, and a relatively short tail when compared to other members of the genus. The upper mandible of the bill is dark, while the lower mandible is orange-pink.
Their breeding habitat is wet northern woods, especially spruce bogs, across Canada and the northeastern United States. They make a cup nest in sphagnum moss on or near the ground.
These birds migrate to southern Mexico and Central America.
Yellow-bellied Flycatchers wait on a perch low or in the middle of a tree and fly out to catch insects in flight, sometimes hovering over foliage. They sometimes eat berries or seeds.
The Yellow-bellied Flycatcher's song can be transcribed as a rough, descending "TSE-berk," which can be similar to the more common Least Flycatcher's snappier, more evenly pitched "che-bek." The three primary call notes of Yellow-bellied Flycatcher are a clear, ascending "chu-wee," a sharp, gruff "peekk", and a soft, descending "pyu."