Birds hurt and killed in Chicago as weekend flying collisions with buildings exceed 1,000

Weekend toll in the city

Chicago Bird Collision Monitors volunteers worked downtown on Saturday and Sunday, rescuing injured birds and recording fatalities, organizers told Fox 32 Chicago. The reported toll from building collisions exceeded 1,000 birds.

More than 100 million birds pass through Chicago each year during seasonal migration, according to Lincoln Park Zoo. Skyscrapers with transparent or reflective windows can pose a danger because birds may not recognize the glass or may mistake reflections for trees or sky.

Windows pose a migration hazard

Annette Prince, director of Chicago Bird Collision Monitors, said the city’s location on a major migration route contributes to large collision events. Birds can hit buildings at speeds of 30 miles per hour, sometimes suffering severe injuries or dying.

The zoo says volunteers collect more than 10,000 dead birds annually after window collisions. Bird-safe approaches include patterned glass, exterior screens and other treatments designed to make windows visible to birds.

Proposed rules and past changes

Nearly 1,000 birds died in one night in October 2023 after hitting McCormick Place Lakeside Center. The advocacy group says changes made to the building afterward improved window visibility and reduced collisions by 95 percent. The proposal’s next steps were not immediately clear.