A whippoorwill is a medium-sized North American bird famous for its distinctive, repetitive nighttime song that sounds remarkably like its own name: “whip-poor-WILL, whip-poor-WILL, whip-poor-WILL.” These birds are most active at dusk and dawn, singing their loud, clear calls hundreds of times in a row. On a quiet spring or summer evening in the eastern United States, you might hear one calling from the woods, repeating its three-note song over and over.

Whippoorwills are related to nightjars and have evolved specialized features for catching insects in mid-air during twilight. Their mottled brown and gray feathers create such perfect camouflage against tree bark and fallen leaves that even if you stand right next to one during the day, you might never spot it.

The bird appears frequently in American poetry, literature, and folk songs because its haunting, persistent call captures something about rural nights and wilderness. Henry David Thoreau wrote about hearing whippoorwills at Walden Pond, and Robert Frost featured them in his poetry. The sound can feel either comforting or eerie, depending on whether you're safe indoors or out in the woods at nightfall.