Monitors Report 1,000 Bird Casualties in Chicago-Area Collisions

More than 1,000 migratory birds were reported killed or injured over the weekend after striking buildings in downtown Chicago and at Northwestern University’s Evanston campus, during peak fall migration. Volunteers said the toll may be higher because monitoring covers limited areas and misses birds on rooftops or those removed before patrols arrive. Reflective and transparent glass can confuse birds, drawing them into windows at high speeds and causing fatal injuries. Bird safety advocates are urging Chicago to adopt an ordinance requiring bird-friendly design in qualifying new construction; the proposal is moving through the city’s legislative process. They point to visible markers added to McCormick Place windows after a 2023 mass collision, which were followed by a reported 95% decline in collisions there, and also support dimming nonessential lights during migration.