The wonder of wandering birds: Forest Preserves of Cook County’s interactive bird-banding map

A leucistic red-tailed hawk banded by the Forest Preserves of Cook County. | Chuck Rizzo

Chris Anchor had just come in from trapping coyotes when he called early morning about the Forest Preserves of Cook County’s recently released interactive bird-banding map.

The conversation covered bird banding, but veered widely.

The Forest Preserves bands most birds—passerines, birds of prey, water birds, waterfowl—except federally listed birds.

A snowy owl banded by the Forest Preserves of Cook County.

“Two birds stand out,” said Anchor, wildlife biologist for the Forest Preserves since 1987.

First was a rough-legged hawk banded in February, 1981 and found five years later in Minganie Regional County in Canada.

“It was collected by a native Canadian, not sure what tribe, and he ate it,’ Anchor said. “He handed the band in.”

There was the great egret banded as a fledgling at the heron rookery at Baker Lake in 2014, then found less than a year later at Cape Canaveral, where it was trapped and released by a federal biologist.

Forest Preserves staff typically band five -20 sandhill cranes, depending on such things as weather, each year. Two of those have been legally harvested, in Kentucky and Tennessee.

“One guy called, he was so excited,” Anchor said. “Out of a group of 1,500 birds, they shot the banded one.”

Banding of ospreys vary similarly, usually 10-20; but only six last year.

“When banding ospreys, we check for heavy metals in the blood,” Anchor said.

That’s notable because heavy metals last a relatively short time in the blood, unlike much longer in tissue. Heavy metal levels in chicks is valuable as a real-time environmental assessment of the area, because it is presumed the parents are collecting food nearby.

The Forest Preserves claim “the most successful urban osprey program of its kind in North America, with 20 osprey nesting platforms.”

That’s a healthy sign

“Everything in my office is based on diseases,” Anchor said.

That’s important to note. It’s not just an academic pursuit, but of practical importance in the handling animals, parasites, and seeing how diseases move across of the landscape.

An example of the importance of tracking zoonotic diseases, ones that may spread across species, is avian influenza, which popped up again in Indiana recently.

Anchor said banding and testing of shore birds, which can be intercontinental travelers, is one way to tracking avian influenza. History shows that avian influenza is less of a concern in North America where humans typically are not living with livestock.

File photo of Chris Anchor, wildlife biologist for the Forest Preserves of Cook County, explaining a project working with turtles.

“The foundation is zoonotic diseases,” Anchor said. “Anyone can see the benefit of that. Someone has to be out in the field collecting.

“I maintain in my office ultra-cold freezers and have blood samples going back decades. . . . [It’s] like a library going back decades.”

With modern advancements, just a tiny bit is needed for assessments, such as testing for lead.

They are looking at zoonotic diseases that impact not only humans but companion animals, too.

Transmitters and banding help gather vital information. Transmitters on local double-crested cormorants found two groups: one hunted locally, another group was going to the Illinois River and the Mississippi River.

“Why go so far?” Anchor asked. “Who knows why they were doing it.”

That matters because after one meal of invasive carp, cormorants will shed eDNA. If that invasive carp eDNA shows up in surveys in the wrong place, it can trigger unnecessary massive searches for bighead and silver carp.

A practical side to the interactive map is both informing the public and keeping the public in on what public servants are doing.

Or as Anchor put it, “I am using it as a tool to suck the public in. We all know from school birds migrate.”

Enjoy the interactive map at storymaps.arcgis.com/stories/a8d2e11a84cc4e439a9423f93b481813.

Work banding birds being done by the Forest Preserves of Cook County.