Chicago plays a key role in annual bird migrations, says expert – NBC Chicago

As hundreds of millions of birds migrate north for their spring breeding season, the city of Chicago plays a critical role in protecting the animals.

Benjamin Van Doren, an assistant professor of environmental sciences at the University of Illinois at Urbana-Champaign, says Chicago’s location in the Midwest and along the Great Lakes puts it right at the epicenter of the flight path of millions of birds.

“Chicago is a city that is on a very important flyway for migratory birds,” he said. “It’s right on the Great Lakes, and a lot of birds pass through.”

These bird species continue to pass through in breathtaking numbers in recent days, with 24.5 million birds flying in Illinois on Sunday evening around 11 p.m. More than seven million birds left the state on their way north to breeding grounds in Wisconsin and Canada, passing through everything from yellow warblers to Baltimore Orioles.

Van Doren wants to remind Chicagoans of the crucial role the city plays in protecting birds, something the city has struggled to fulfill.

“Chicago is the city that probably exposes the most migratory birds to the most light pollution of any U.S. city,” he said.

Lights Out Chicago has been encouraging companies to participate since the 1990s.

Companies and apartments are asked to turn off or dim the outdoor lighting of multi-storey buildings. Buildings are also asked to turn off or dim the maximum amount of lobby lighting between 11 p.m. and 6 a.m.

Birds are most active around 11 p.m. and typically begin their nighttime flights 30 to 45 minutes after sunset.

Even subtle changes like rain in the forecast can cause birds to delay their flights, meaning dry weather spells like Chicago on Sunday and Monday could send even more birds into the sky.

“Birds are actually very selective when they move during both spring and fall migrations, so birds typically won’t decide to migrate if there are strong headwinds or if it’s raining,” he said.

According to Birdcast, more than 320 million birds have already crossed the state during spring migration, which is above average for this time of year, something Van Doren said is happening due to the effects of climate change.

“As the climate warms and the weather generally warms in the spring, migrations become earlier and earlier as birds try to adapt to the changing weather and climate,” Van Doren said.

Chicago is expected to see large numbers of migratory birds on both Monday and Tuesday evenings, with residents urged to take steps to protect the animals.

You can find more information about the Lights Out Chicago program on the city’s website and access Birdcast maps through Colorado State University and the Cornell Lab of Ornithology.