In past years one could often see and hear the common nighthawk as it circled in the glow of streetlights, picking off moths and other insects attracted by the glare. This bird would even nest within city limits on gravel surfaces of flat rooftops. Unfortunately its numbers have dropped markedly in the past forty years, and it is now seen only occasionally in small numbers in the Newton area.
Nighthawks gather in loose flocks to migrate south in late summer. Your best chance of seeing one is during the last week in August or in early September. Choose a high vantage point overlooking a wide, open area where visibility is good, and keep watch of the sky during the hour before sunset. The old baseball field at Cold Spring Park and the open area over the Charles River near Cutler Park are good spots to check for migrating nighthawks.