Species most commonly killed during these events are ovenbirds, common yellowthroats, white-throated sparrows, black-throated blue warblers and gray catbirds.
The Audubon Society called last year s event Philadelphia s largest mass collision in 70 years. When they occur at that scale, there are often confounding weather patterns that further reduce visibility and confuse migrating birds, who are especially prone to reflections in windows.
Notable buildings participating in Lights Out Philly include BNY Mellon Center, Comcast Technology Center, Comcast Center, Jefferson Center, One South Broad, One Liberty Place, Two Liberty Place and 1515 Market Street.
During the hours covered by the program, these and other buildings will shut off lights on upper levels and in lobbies and atriums. External lighting will either be turned off or dimmed.