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Up To 200 Birds A Night Die Crashing Into McCormick Place Windows. Turning Off Half The Lights Could Save Them, Study Finds

A new study shows birds are attracted to lit windows — which results in deadly collisions. Turning off half the lights at McCormick Place could result in a nearly 60 percent drop in birds crashing, Field Museum researchers found.

McCormick Place
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CHICAGO — Turning out half the lights at McCormick Place could result in a nearly 60 percent drop in birds crashing into the windows and dying during migratory season, a new analysis found.

David Willard, the collections manager emeritus at the Field Museum, spent more than 40 years investigating bird collisions at the famous convention center. A newly published study using decades of data shows that on nights when half the windows at McCormick Place were dark, there were 11 times fewer bird collisions during the spring migration season and six times fewer collisions during the fall migration, according to a Field news release.

The data shows birds are attracted to lit windows — which could result in deadly collisions, according to the researchers. In turn, shutting off the lights at McCormick Place and other Downtown buildings on high-risk nights would save birds.

RELATED: Chicago’s The Most Dangerous City For Migrating Birds In The Fall. Here’s How To Help Them

“The sheer strength of the link between lighting and collisions was surprising,” Benjamin Van Doren, the paper’s lead author, said in a statement. “It speaks to the exciting potential to save birds simply by reducing light pollution.”

Willard started investigating bird collisions at McCormick Place in 1978; over the years, he’s been joined by others, who go to the convention center every day before sunrise to check for dead birds. They sometimes find no birds — but there have been days where they’ve found up to 200, according to the Field.

The group collects the birds at the Field Museum and, over the years, started taking notes on how many windows were lit and where at McCormick. The study shows that more windows left lit overnight resulted in more bird collisions and deaths.

The number of birds in the sky and the direction of wind also played a role in bird deaths, but the “biggest determining factor was light: when more windows were darkened, fewer birds died,” according to the Field.

McCormick Center is especially dangerous for birds because it’s an enormous building, it is isolated from other buildings and it’s close to Lake Michigan, which birds can be hesitant to fly over, according to the Field.

But buildings throughout the city — and throughout the world — kill birds.

“What we’ve learned in the past 20 years about lights being on has caused the city of Chicago to create its Lights Out program, which requires buildings’ external lights to be turned off during peak migration,” Doug Stotz, a senior conservation ecologist at the Field, said in a statement. “I hope this paper will show why it’s important to turn off internal lighting as well, especially in Chicago, which is the country’s deadliest city for migrating birds.”

Van Doren said he hopes officials will use these findings to issue lights-out advisories for buildings during nights when there’s a high risk of bird collisions.

“Our study contains a hopeful message: we can save birds simply by turning off lights during a handful of high-risk days each spring and fall,” Van Doren said in a statement.

People who come across birds injured by a collision can help by gently putting the bird inside a paper bag or a box with a lid and calling the Chicago Bird Collision Monitors at 773-988-1867.

The Chicago Bird Collision Monitors work with volunteers who will pick up the bird and take him or her to a wildlife center for a health checkup. The bird will be safely released once well so he or she can continue migrating.

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