Kentucky Warbler

Kentucky Warbler (Birds of North Carolina: their Distribution and Abundance)
Though a common bird west of the Appalachians, east of the mountains it is nowhere really common. It is almost always found nesting in moist, rich forest, with an abundance of ferns and other herbaceous species, as well as a good shrub zone, beneath a hardwood canopy. Most breed in floodplains, particularly in brownwater ones. In many parts of the state, this species has noticeably declined in the breeding season, especially in heavily populated counties in the Piedmont; Kentucky Warblers fare poorly when bottomland forests are impacted by exotic plants and other small disturbances.

Kentucky Warbler (allaboutbirds.org)
The Kentucky Warbler’s loud, rolling song rings out from dense forest understories, where these hard-to-see warblers hunt for arthropods on or near the ground. Kentucky Warblers are brilliant yellow below and rich olive above, with a black cap and cheek and bold yellow “spectacles” that don’t quite wrap around the eyes. They spend winters in Mexico and Central America, where they forage near ground level and often follow army ant swarms to catch fleeing insects.

Kentucky Warbler Song (Youtube video, American Bird Conservancy)

How to Tell Apart Sound-Alike Warblers (Audubon)
Of course, using bird songs to track down your favorite species requires knowing the singer. And some species can sound very similar to their cousins. Let’s consider a few of these confusing songs—and their spectrograms—in preparation for our upcoming migrant arrivals.