The tiny flycatchers of the genus Empidonax are notoriously difficult to identify by visual clues alone. Determining the species by sight requires a good look under ideal conditions. Even then, these birds are a tricky lot. Don’t believe it? Take a gander at these photos of an Empidonax flycatcher found atop Second Mountain in Lebanon County at sunrise this morning…
One of the telltale signs of an Empidonax flycatcher from outside the group of eastern species is the presence of an expanded rear edge of a well-defined eye ring.Only the Pacific-slope and Cordilleran Flycatchers, groups currently lumped together by taxonomists as the Western Flycatcher, exhibit the teardrop-shaped eye ring. In the lower Susquehanna region, Western Flycatchers have been recorded as vagrants during autumn and in early winter on several occasions, most recently along the river in Conoy Township, Lancaster County, in December of 2023. (See post from December 20, 2023)For now, that 2023 record will remain the most recent. With a turn of its head providing a better angle in direct sunlight, the apparent expansion of the rear portion of the eye ring turns out to be little more than a pale post-ocular feather on this bird. The broad (but uniform) eye ring, rounded head, small bill, short tail, and the unbroken coloration of the underside areas all conspire to indicate that this is probably a Yellow-bellied Flycatcher (Empidonax flaviventris). Disappointing? Hardly. Yellow-bellied Flycatchers are strictly migrants in the Lower Susquehanna River Watershed. They are rarely seen as they pass through traveling to and from their breeding grounds in the moist coniferous forests, bogs, and swamps of the northernmost United States and southern Canada. A Neotropical species, the Yellow-bellied Flycatcher winters in southern Mexico and Central America.
