Researchers with the Cornell Lab of Ornithology are asking Chicago area businesses and homes to turn off or limit exterior lights this week, as bright lights can endanger the thousands of birds that are expected to move through the region on their migrations to the south.
According to the Birdcast website, a “Lights Out Alert” has been issued for the Chicago area for Sunday night and into Monday morning. Large numbers of birds, sometimes exceeding 16,000 per hour, are expected to migrate over the city of Chicago between 11 p.m. Sunday and 6 a.m. Monday.
Bright lights attract and disorient birds that fly during the overnight hours, potentially causing serious or fatal injuries for birds when they strike buildings.
Business and homeowners are asked to turn off all non-essential lighting during that time to help protect the birds as they make their way through the area.
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Researchers estimate that hundreds of millions of birds die in collisions with buildings annually.
In addition to shutting off non-essential exterior lights, owners are also asked to dim non-essential lights in atriums and lobbies, and to install covers over outdoor exterior lights to direct that light toward the ground.
The fall migration season approximately runs from Aug. 15 to Nov. 30.