10/14/2026
Black-crowned Night Herons across Chicagoland! 🌙
Look at that spread!
This fall 2026 snapshot from the Chicago Bird Migration Monitoring Network shows potential detections of Illinois-endangered Black-crowned Night Herons at listening sites across the region.
The blue circle marks the acoustic monitor atop the Peggy Notebaert Nature Museum, near the Lincoln Park Zoo rookery. Its 1,023 detections make sense given that location. But look farther afield: 69 detections at a Peotone farm, 57 in DuPage County, 48 at Salt Creek, 29 in Portage, and 21 in Barrington.
The story of our herons doesn’t end at the rookery. Nesting habitat is vital, but birds also need suitable places across the wider landscape. Understanding where they’re detected can help us ask better questions about where they feed, how they move through the region, and what they need to thrive.
The Chicago Bird Migration Monitoring Network tracks migratory birds across Chicagoland using acoustics, thermal imagery, radar, and other technologies. Chicago-based Windy City Bird Lab is one of the network’s organizers, working with researchers at the University of Illinois Urbana-Champaign and Duke University. The network monitors many bird species that make nocturnal flight calls, not just herons.
A note on the data: these are preliminary automated detections, not confirmed counts of individual birds, and may include errors. They don’t establish individual migration routes, but the regional pattern is intriguing and worth investigating.
Curious where else birds are being detected? Google Chicago Bird Migration Monitoring Network to explore the live dashboard.