Common Nighthawk

From U.S. Fish and Wildlife Service Midwest Region:

Common nighthawks will start migrating with the cooler nights of late August and early September. These long-distance travelers move in large flocks at all hours of the day, all the way to their wintering grounds in South America.

Photo: Common nighthawk courtesy of Brian Garrett/Creative Commons.https://flic.kr/p/bWqSGm