About 1,000 songbirds died last week after flying into a Chicago convention center during their migratory journey south.
The birds crashed into McCormick Place Lakeside Center, a mostly-glass building located on the shore of Lake Michigan, on the night of Oct. 5.
The convention center said on their Instagram the “unusual weather conditions” coupled with avian confusion from the light that is emitted from buildings like their own is to blame.
"In one night we had a year's worth of death," Douglas Stotz, a conservation ecologist with the Chicago-based Field Museum, told NPR.
He said the museum regularly monitors the convention center for dead or injured birds, and typically between 1,000 and 2,000 die each year from flying into the building.
"It would have made a huge difference to have the lights off," Stotz said to NPR.
Turning out the lights in tall structures during the spring and fall migration dates helps reduce confusion for the birds, especially since some species rely on the stars for navigation at night.
The convention center is one of Chicago’s buildings that participates in the city’s voluntary “Lights Out” program, which asks tall buildings to cut their lights every night during peak migration season.
"Lighting at McCormick Place is turned off unless needed for our employees, clients, or visitors," the convention center said in the Instagram statement. "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."
Window strikes are not an issue exclusive to the Windy City. Researchers estimated up to one billion birds are killed in window strikes across the United States each year, according to a study done in 2014.
Birds don't have the capability of distinguishing reflective glass and don't comprehend it's a lethal barrier. Often they circle the buildings repeatedly and die of exhaustion or collision. That’s why organizations like the Chicago Bird Collision Monitors are pushing for construction of buildings with bird safety in mind.
Chicago Bird Collision Monitors also joined the Chicago Audubon Society and the Chicago Ornithological Society in creating an online petition asking political leaders in Illinois and Chicago to make it a requirement for McCormick Place to have their interior lights turned off or their shades drawn every night of migration following the unusually high number of dead birds.
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