Breeding birds are doing better in the Chicago region than the rest of Illinois, according to a decades-long survey of the region’s natural areas conducted by a local conservation coalition.
The six counties in and around the Windy City host over 100 nesting bird species, and more than half (56%) of those species are stable or increasing around Chicagoland. Elsewhere in Illinois, only 37% of those species are on similar trajectories.
“When you think of an area that’s more developed like Chicago, people tend to think you’re not going to see as many birds there as you would in more rural places,” said Eric Secker, president of the Bird Conservation Network, the collaboration of 21 organizations (including American Bird Conservancy and the Illinois Audubon Society) that conducted and published the study.
“The birds here are doing better because of the fact that even though it’s a suburban and urban area, there’s a lot more areas that are protected and preserved.”
Across Illinois, only 4% of total land is preserved in the form of public and private parks, land trusts, or easements. But 9.5% of land in the Chicago area is protected for wildlife in county preserves and state parks. That includes a lot of managed grasslands, and grassland birds around Chicago responded with population increases that buck national trends.
For example, Henslow’s Sparrows—a tallgrass prairie species that has declined nationally over the last 50 years—increased in the survey area by over 3% every year since 1999. According to Secker, the species is responding well to prescribed burns and grassland management at Chicago-area preserves, such as Springbrook Prairie Forest Preserve and Nelson Lake Marsh Nature Preserve.
“In no place in the world will you find a greater concentration of Henslow’s Sparrows than in northeastern Illinois,” added Jim Herkert, former executive director of the Illinois Audubon Society. “It is a globally important landscape for this bird.” See Henslow’s Sparrow abundance mapped in more detail via eBird Status and Trends.
Chicago-area birds were doing well in other habitats, too. About 60% of species in woodlands were either stable or increasing—including Red-headed Woodpecker, a bird that has declined by 67% globally since 1970 but doubled its population in the survey area since 1999. Secker said that effective management of oak savanna woodlands helped the woodpeckers.
Some birds, however, didn’t show increases around Chicago. The regional Bobolink population shrank by almost 3% each year over the course of the study, which is an even steeper drop than the national trend for the species (but still less severe than Bobolink declines in the rest of Illinois).
“It’s definitely challenging to manage for a whole suite of species because what helps one could go the opposite for another,” Secker said. Still, the Bird Conservation Network is searching for solutions to benefit the whole community of grassland birds, such as a hedgerow removal project that will create contiguous grassland habitat.
The study relied on hundreds of volunteers to monitor the region’s natural lands over two decades. The final analysis included nearly 30,000 surveys from over 2,000 sites, with all that data managed via a collaboration with a Cornell Lab of Ornithology eBird customized data management platform.
Benjamin Hack’s work on this story as a student editorial assistant was made possible by the Cornell Lab of Ornithology Science Communications Fund, with support from Jay Branegan (Cornell ’72) and Stefania Pittaluga.