Last Thursday morning, there was an eerie sight outside of Chicago‘s McCormick Place building — at least 1,000 dead birds littered across the pavement.
The migrating birds died during an apparent collision with the McCormick Place Lakeside Center, North America’s largest (and highly windowed) convention centre. The Washington Post reported there were warblers, woodcocks and sapsuckers among other species of dead songbirds.
On Monday, volunteers were still picking up dead birds from in the area around the largely glass-walled building.
Annette Prince, the director of Chicago Bird Collision Monitors, told the Washington Post the loss of bird life is alarming. The Chicago Bird Collision Monitors is a volunteer-based organization dedicated to the protection of migratory birds through rescue, advocacy and public outreach.
“When we say we found a thousand birds, that’s just a snapshot — beyond the one square mile we look at, there could be so many more,” Prince told the Washington Post.
Prince told The Guardian the bird strikes from Wednesday night and Thursday morning are unlike any the Chicago Bird Collision Monitors has ever seen before. She said weather conditions, namely brisk winds and cloudy skies (along with the building’s glass windows), made the “perfect storm” for bird strikes.
The lights at McCormick Place were also left on after hours on Thursday night to accommodate an event. Most species of migratory birds are known to become disoriented by light pollution, which can lead them to collide with structures and windows.
McCormick Place defended its decision to keep the lights on in a statement shared Saturday. While noting the “extremely large number” of dead migratory birds, the building owners said they are already “actively involved in bird conservation efforts,” including bird sanctuary maintenance and community outreach.
The statement claimed the convention centre normally participates in the Lights Out Chicago program, an initiative that sees buildings in the city turn off or dim their lights to combat bird strikes.
“Lighting at McCormick Place is turned off unless needed for our employees, clients, or visitors,” the statement said. “It is important to understand that there is an event going on at Lakeside Center this week, and thus the lights have been on when the space is occupied. As soon as the space is unoccupied, the lights have been turned off.”
McCormick Place said it is currently working to find “better solutions to protecting our avian neighbors.”
A 2021 study of the building found that shutting off even half of the lights at McCormick Place reduced the number of bird collisions by six to 11 times.
David Willard, who has been patrolling the grounds of the lakefront exhibition center in search of dead birds for 40 years, told the Associated Press he’d never seen anything like the carnage discovered on Thursday morning.
“It was just like a carpet of dead birds at the windows,” said Willard, a retired bird division collections manager at the Chicago Field Museum.
Willard said a typical night would yield up to 15 birds dead from strikes.
“In 40 years of keeping track of what’s happening at McCormick, we’ve never seen anything remotely on that scale,” he said.
Bird window strikes are not exclusive to Chicago; of all U.S. cities, Chicago reportedly poses the greatest risk for migrating birds because of its light pollution.
In Canada, window collisions kill 16 to 42 million birds every year. This is significantly less than the 365 million to 988 million birds killed in window collisions in the U.S. each year.
Most birds die on impact. Ones that do not often succumb to life-threatening injuries shortly thereafter.
The welfare of birds is not just important for species preservation, but also for the environment as a whole. Birds are necessary for pest control, pollination and seed dispersal in nature.
— With files from The Associated Press