vireo (bird) philadelphicus (of the city of Philadelphia, where it was first collected by John Cassin in 1851)
Saturday, May 15, 1982 — 10:00 am
Elk Grove Village, Illinois — Busse Woods
This must have been the stage of my birding experience when I gained the expertise necessary to identify vireos. I got three lifer vireos in a week. I tracked this one down by its song. It was foraging slowly through the woods, moving branch to branch, up and down from treetops to under-story (as low as 15 feet above the ground). It was picking at leaves and occasionally fluttering out like a flycatcher. It often stopped to sing. It moved slower than the warblers that were foraging nearby. I spotted a Red-eyed Vireo about five minutes later. The Philadelphia Vireo was smaller, and its song, although similar, was slower and not as continuous.