Chicago City Council to consider building requirements to protect migratory birds

Millions of birds are making their fall migration, but Chicago's buildings and glass can make their journey deadly.

Bird advocates estimate tens of thousands of birds die from building collisions in Chicago each year. But this month, the Chicago City Council is set to consider an ordinance that could establish bird-friendly requirements for new construction and major renovations.

Annette Prince, director of Chicago Bird Collision Monitors, explained that Chicago has been on migratory birds' path long before the city even existed.

"It was a safe route, through the center of the country, and they have been using this as a place to rest, as they're making incredible travels between as far north as northern Canada to South America, and now we've put obstacles in their way," she said.

Most birds fly at night, and encounter nighttime lighting in the city that confuses them, Prince explained. Glass windows likewise pose a problem.

"When they settle or stop by the city, they're experiencing a very foreign environment with glass that is deadly for them, because it's either reflective, and it looks like a mirror that they fly towards, or it's transparent, and they are trying to fly through areas that have, obviously, a solid barrier that they have never had experience with in the times they've spent in the forests and the rainforests of the world," said Prince.

Chicago Bird Collision Monitors believes that voluntary measures to protect birds are not enough, and that Chicago needs mandatory standards. The organization also wants residents to take action on their own.

"Chicago being listed as the city that is the worst for North American birds, as far as the hazards that we provide, we should be the city that puts this in place and is a leader in finding new products and new ways to design buildings," Prince said. "So we need residents of Chicago, people who live or work in the city, to contact their alderpersons and let them know that this is important to them."

Prince said with a simple retrofit in 2024, McCormick Place reduced its number of bird strikes by 95%. This came after the convention center had 1,000 birds die in one morning.

Cornell Lab of Ornithology's BirdCast showed 527.3 million birds migrated across the country just before 11 p.m. Saturday, Sept. 5.

The proposed bird-friendly building ordinance could be considered by the Chicago City Council this month.