Bird Banding & Research in Cook County

Forest Preserves of Cook County

The  Forest Preserves of Cook County  bands birds—from sparrows to sandhill cranes—as part of ongoing research that helps track ecosystem health, migration patterns and zoonotic diseases (illnesses passed between animals and humans). Forest Preserves biologists safely capture, handle and band an average of 400 birds per year.

A USGS band attached to the leg of an osprey chick.

What is Bird Banding?

Bird banding involves humanely capturing a bird for a brief time and attaching a lightweight U.S. Geological Survey (USGS) band, usually on the bird's leg. When banding, Forest Preserves biologists also perform health workups, which may include taking measurements, determining a bird's sex, drawing a blood sample, and looking for any indication of disease.

A mist net—nylon mesh held up between two fixed poles—is used to capture smaller birds that fly by, like American robins and Baltimore orioles. Raptors, like hawks and owls, can be captured in a larger, sturdier version of a mist net or in a trap baited with prey. Forest Preserves biologists also visit our osprey platforms and heron rookeries each year to band these larger birds as chicks or fledglings, when handling them is easier and safer—for the birds and our staff.

Please note: In the United States the banding of birds is regulated under the  Migratory Bird Treaty Act  and requires a federal banding permit. The Forest Preserves is authorized to capture, handle and band birds through a permit from the  Federal Bird Banding Laboratory .

Why Band Birds?

Attaching a USGS band allows anyone who finds the band (with or without the bird) to report where they found it, giving researchers insight into the bird's travels. If another researcher captures the bird, or Forest Preserves biologists recapture the bird, it provides an opportunity to perform another health workup and compare it to past results.

“By tracking the birds’ movements and conducting continued health assessments, we can find out what diseases the bird has been exposed to and what kind of titer it’s throwing. [Titer is the concentration of antibodies in the blood.] It can tell us whether the animal has active disease, what it’s been exposed to and sometimes when it was exposed.” Chris Anchor Forest Preserves senior wildlife biologist

The Forest Preserves contributes its bird banding data to the  USGS Bird Banding Laboratory’s worldwide scientific database , which is used to monitor resident and migratory bird populations. The health workups Forest Preserves biologists perform during banding operations help the  Centers for Disease Control and Prevention , public health departments and international researchers track zoonotic diseases. Additionally, birds serve as important bioindicators of environmental issues locally, helping to uncover sources of pollution or measure the success of  restoration efforts .

Learn more about the Forest Preserves' research collaborations and restoration efforts:

Where Have Banded Birds Been Rediscovered?

Explore where birds banded by Forest Preserves biologists have been found—locally, in other states, and even in Canada!

Banding at Baker's Lake Heron Rookery

Each year, after a short boat ride from the shores of  Baker’s Lake  in northwest Cook County, wildlife biologists and veterinarians visit a small island with a towering wooden rookery to conduct health work ups and band birds. The rookery is home to about 300 nests for great egrets, great blue herons and double-crested cormorants, which flood the manmade structure in spring and early summer.

In addition to the Baker’s Lake rookery, the Forest Preserves has rookeries at  Busse Woods ,  McGinnis Slough ,  Powderhorn Lake  and other preserves.

Osprey Propagation Program Banding

The Forest Preserves osprey propagation program started in the late 1980s to help osprey populations recover from major declines due in part to DDT insecticide use from the 1950s to early 1970s. The Forest Preserves now boasts the most successful urban osprey program of its kind in North America, with 20 osprey nesting platforms.

Forest Preserves osprey nesting platforms generally feature a 50-foot post with a predator guard, supporting a 40-inch-wide platform. These platforms are placed in areas where osprey have consistently tried to nest in trees without success due to predators and weather-related damage.

Many platforms are used by the same osprey pair each year, producing one to four chicks per nest. Osprey colonies have even formed around some of the older platforms.

“Osprey are directly exposed to pollutants that accumulate in aquatic food chains due to their diet of large fish. Because of this they act as important biomonitors, helping to indicate the health of our environment. By banding and performing health work ups on osprey, we can better guide our conservation and restoration efforts.” Melina Frezados Forest Preserves wildlife technician

Forest Preserves biologists monitor active nests, visiting each one in early summer to band and check on the health of the osprey chicks inside. There is a roughly 15-day period when it is safest to handle the chicks (for our staff and the birds), so Forest Preserves biologists need keep a close eye on the osprey platforms to decide when to band the chicks.

Learn more about osprey and the Forest Preserves osprey propagation program:

Snowy Owl Encounter

Photos of the snowy owl banded by Forest Preserves biologists.

In January 2018, reports of snowy owls—rare visitors from the Arctic—hanging out at Chicago's lakefront and in southern Cook County circulated among birders. Forest Preserves biologists observed one of the birds at  Orland Grassland  lingering near a marsh and decided to try to band the bird.

Visiting early one morning as the sun came up, they quickly baited a trap about 130 feet from where the bird was perched. The snowy owl instantly swooped down to the bait and found itself caught in their trap. Biologists completed a health work up and banded the bird, while getting quite a thrill seeing this unique visitor up close during their brief 20-minute encounter.

Snowy owl release at Orland Grassland.

Learn more about snowy owls and this rare visitor:

Hawk Banding Highlights

Hawks are abundant in the Forest Preserves and, because these birds are top predators here, they can tell us a lot about the contaminates and diseases that move through our local ecosystems. Forest Preserves biologists have banded red-tailed hawks, Cooper's hawks, rough-legged hawks and red-shouldered hawks.

Photos of the leucistic red-tailed hawk banded by Forest Preserves biologists.

Leucistic Red-tailed Hawk

Forest Preserves wildlife biologist Chuck Rizzo first spotted this unique looking red-tailed hawk about six years before it was banded. The patchy white areas on the bird's feathers are caused by a condition called leucism. This genetic mutation causes a loss of pigment, which can impact the entire bird or, as with this bird, only certain feathers.

“It is really a great privilege to be able to handle any bird—whether it is a passerine, raptor or other type of bird—and to be able to collect information on it for a better understanding of birds and the environment that we share with them.” Chuck Rizzo Forest Preserves wildlife biologist

Mallophagial lice from a rough-legged hawk under a microscope. Photo by Forest Preserves of Cook County Wildlife Field Office.

Louse-y Hawks

You are looking at mallophagial lice. This particular kind of louse is specific to rough-legged hawks from the Arctic region. In 2015, a Forest Preserves wildlife biologist took a closer look at a rough-legged hawk and discovered these creatures with brilliant contrasting colors in the hawk's head feathers.

Most birds have feather lice. One fascinating aspect of these tiny parasites is that they are specific to certain parts of a bird's body. One species of lice will only live on the head of the bird while another will only inhabit the flight feathers of the wings. Parasites are often vectors for zoonotic disease, so studying them goes hand in hand with the goals of the Forest Preserves banding program.

Red-tailed hawk release at Deer Grove.

Red-tailed Hawk Release

Forest Preserves biologists captured this red-tailed hawk at  Deer Grove  in November 2018. Determining the exact age of a bird is difficult, but judging by the coloration and wear of this red-tailed hawk's feathers and the shade of its eye color, biologists classified it as an "after third year" bird (or a bird that is at least three years old).

After doing a health work up and banding the hawk, they documented its release in this slow motion video. Watch carefully around the six second mark and you'll notice the hawk draw its nictitating membranes across its eyes. These protective “third eyelids” allow the hawk to clean and protect the surface of its eyes while maintaining the ability to see.

Educating Future Wildlife Biologists & Researchers

 

First photo: Forest Preserves wildlife technician Melina Frezados (second from left) shows university biology students how to properly handle and examine a hawk. Second photo:  Forest Preserves Conservation Corps members  observe an osprey banding.

The Forest Preserves hosts university biology and veterinary students from schools across the Midwest—including Judson University, North Park University, The Ohio State University, Purdue University, University of Illinois at Urbana-Champaign, and University of Wisconsin–Stevens Point—to help them gain field experience as they pursue careers as wildlife biologists, veterinarians and researchers. Students spend up to a week helping the Forest Preserves conduct ongoing research with deer, coyotes, birds and more. Forest Preserves wildlife biologists teach students how to safely and humanely capture and handle wildlife, take measurements, perform health work ups, use radiotelemetry and more.

At the end of their time with the Forest Preserves, students have gained valuable field experience and made the connection between this hands-on work and the important ongoing research that monitors wildlife populations for toxins and zoonotic diseases.

In addition to hosting university students, Forest Preserves wildlife biologists invite  Conservation Corps program members  to observe osprey banding, turtle tagging and other field work, helping to spark an interest in conservation careers.

About the Forest Preserves of Cook County

Don’t you sometimes just want to escape? Explore the natural beauty of Cook County for an hour, a day or even a night. When you’re surrounded by 70,000 acres of wild and wonderful, there’s no better place to feel free.

A USGS band attached to the leg of an osprey chick.

Mallophagial lice from a rough-legged hawk under a microscope. Photo by Forest Preserves of Cook County Wildlife Field Office.