Mike Ward walks through the Rutland Forest Preserve in Kane County holding a pair of binoculars, searching the trees for birds. But he rarely uses the binoculars. Instead, he rattles off which birds are flying by purely by sound.

“That high-pitched call was a cedar waxwing,” Ward explained, swatting away mosquitoes swarming after a recent rainfall. He also easily identifies a robin, a chickadee, and a cardinal calling.

As avian ecologist at the University of Illinois at Urbana-Champaign, Ward has studied birds for more than two decades. His latest project is among his most ambitious — he and a team of researchers are looking for ways to help save native Illinois birds for decades to come.

They retraced the steps of two ornithologists, Stephen Forbes and Alfred Gross, who conducted the first statewide bird survey in between 1906-1909. Forbes and Gross traveled across the state by train and on foot. They didn’t have binoculars, so they shot the birds to identify them. In their survey, Ward and his team identified birds strictly by sight.

These modern bird scientists are documenting which bird species saw population changes over the last century. They also looked at where birds have found new homes as Illinois farmlands have turned into suburbs and big cities. This helps conservationists better understand which birds have used changing landscapes to thrive and which ones are struggling.

“If we can predict 50 to 100 years from now which birds are going to be in trouble, we can use our limited resources to try to conserve the birds that are in most need of it,” Ward said, looking up at the trees, his eyes darting as he searched for more birds.

Overall, Ward and his colleagues found 26 of the 66 species analyzed decreased in population over the past century, while 40 species increased. A species’ fate highly depends on how well they adapt to certain environments, namely urban and suburban development.

If a bird could adapt to modern sprawl, it likely increased in population.

Many birds still prefer to live in forests, which haven’t changed much in Illinois over the last 100 years. But bird species that learned to go beyond the forest and live in urban habitats usually increased their numbers over the century.

“So like the cardinal, which is our state bird, didn’t even occur [in Kane County] 100 years ago. It was a forest bird in Southern Illinois,” Ward said. “Then it realized, why don’t I hang out in people’s backyards?”

Urban and suburban dwellers also became more accustomed to birds living near them.

Although forestland has remained stable over time, grasslands and pastures have declined across Illinois. As a result, birds that preferred those habitats are seeing declines, the researchers found. Many of those bird species also do well around farmland. But as agriculture has become more manicured and technology has made farming more efficient, it’s made it hard for birds to survive.

“It’s not that the crops are hurting the birds per se, it’s that there aren’t weeds for birds to feed on or insects for them to feed on,” Ward explained.

Ward said it’s difficult to know why a particular bird might be better at living in a certain environment than others. It’s also unclear if a bird’s decision to live closer to people, whether in their backyards or in a city, is a learned behavior or if genetics play a role.

But documenting how birds respond to Illinois’ changing landscape — whether it’s learned behavior or genetics — can be used to make habitats more wildlife-friendly, and ultimately, bolster the bird populations.

“Small things in your backyard can go a long way,” Ward said. “So, as we move decades forward … the species that are going to do well are species that adapt to humans — but humans have to give them the ability to adapt.”

He suggests bird houses, feeders, or bird baths, and mowing less so birds have weeds and plants to feed on. That not only helps birds that live in the area, but also helps birds during migration.

“We’ll probably lose a couple species, but I’m optimistic we’re moving in the right direction. I just hope it continues,” he said.

Kate McGee covers education for WBEZ. Follow her on Twitter at @WBEZeducation and @McGeeReports.

