Because of adverse weather conditions and city lights, a major migration collision killed 960 birds after they crashed into the McCormick Place convention building in Chicago on Oct. 5, 2023, according to Cornell Lab experts on BirdCast.
“Prior to this, the highest number [of birds] I've ever found at McCormick in one night is 250, which seems massive to start with,” says David Willard, a retired collection manager at Chicago’s Field Museum, who is still involved with the institution.
How Many Birds Die From Windows?
While the numbers are shocking for a single building, 100 million to 1 billion birds die annually in the U.S. from window collisions alone, according to the U.S. Fish and Wildlife Service.
“This one dramatic night shouldn't obscure the fact that there's almost no night during migration [season] when smaller numbers of birds are hitting windows,” Willard says.
