Researchers estimate that hundreds of millions of birds die hitting buildings every year in the United States. Striking buildings is believed to be one of the major factors behind the nearly 30% decline in North American bird populations since 1970.
Chicago is one of the most dangerous cities for migrating birds based on its location and its numerous tall, glassy buildings. Migrating birds that make their homes in forests and grasslands don’t perceive glass as solid and are confused by reflections.
While many Chicago skyscrapers are dangerous for birds, the Lakeside Center at McCormick Place is infamous for the fact that it claimed the lives of nearly a thousand birds on a single day in October 2023.
There are various strategies for reducing bird strikes. Over decades, McCormick Place management has tried erecting strips of netting, broadcasting calls of birds of prey, and putting up silhouettes of them. They commissioned a nine-acre park of native prairie and woodlands on the roof of a parking deck. None of these things made a major difference.
Last summer, the building installed a pattern of dots over the surface of the building’s windows. The dots are only a couple of inches apart, so even tiny hummingbirds don’t try to dart through. The window treatment cost $1.2 million paid for by the state of Illinois. People in the building scarcely notice the dots. Their views of the city and lake are unimpaired.
The results are nothing short of remarkable. During last fall’s migration, bird deaths were down by about 95% compared with the two previous autumns. This spring’s migration has been with implications for glassy structures far beyond Chicago.
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An Illinois Building Was a Bird Killer. A Simple Change Made a World of Difference.
Photo, posted May 19, 2023, courtesy of Warren LeMay via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio