September 9, 2007 - Flying Cigars Welcome to the Nature Notebook. A black cloud swirls in a clear, twilight sky, twisting about as it flies overhead. A chimney appears to suck down this living cloud as darkness falls. Chimney swifts, gathering for fall migration, have found a roost for the night. Swifts look like dark, flying cigars with long, narrow curved wings. Their small, weak feet only allow them to cling to vertical surfaces; they cannot perch like most birds. During the day swifts ply the air with rapid wingbeats and open mouths gobbling up insects while performing aerial acrobatics. Their nightly roosts in chimneys can be their undoing, however. Cooling autumn nights prompt people to kindle fires in their fireplaces or call a chimney sweep to clean the chimneys. Swifts fall victim to both each year. But the ones that survive make their way south to spend the winter where food is abundant. This is PPL's naturalist, Jon Beam, with the Nature Notebook for WVIA.