(University of Illinois, Photo: Michael Jeffords, February 27, 2017)
An iconic bird whose booming mating calls once reverberated across “the Prairie State” can survive in Illinois with the help of periodic human interventions, researchers report.
The greater prairie chicken once dominated the American Midwest, but today the bird is in trouble in many parts of its historic range. It is no longer found in Arkansas, Indiana, Kentucky, Michigan, Ohio, Tennessee, Texas or Wyoming, states where it once flourished. And in Illinois, an estimated 186 birds remain in two adjoining counties in the southern part of the state.
“They used to be all over the state,” said Illinois Natural History Survey conservation biologist Mark Davis, who participated in a genetic analysis of the Illinois birds. “This was the tallgrass prairie state. You couldn’t throw a rock into a field without hitting a prairie chicken.”
The reason for the decline is simple, Davis said.
“We changed our land-use practices from having a lot of prairie, then to wheat, hay and alfalfa, and now to vast expanses of corn and soybeans,” he said. “Prairie chickens used to have 20 million acres of prairie in Illinois. Now, they have around 2,000. At the same time, population size went from 10 to 14 million in the 1860s to the 100 to 200 or so we have today. There just isn’t enough habitat.”
Environmental officials have made two efforts to rescue Illinois’ dwindling prairie chicken populations, which are suffering from a lack of habitat and declining genetic diversity. Between 1992 and 1998, teams imported more than 200 prairie chickens from other states.
“In Illinois, the first translocation brought in birds from all over the upper Midwest — from North Dakota, Minnesota, Kansas and Nebraska,” Davis said. “And for a short period of time, it seemed to work.” More chicks survived to reproductive age and genetic diversity spiked, he said.