If you think about large, imposing birds that we see soaring above or perched on high while scanning for a meal, raptors like hawks and eagles probably come to mind. Maybe even owls, which are known for their fierce hunting abilities. But there's another kind of raptor we see that can be just as imposing as hawks, eagles and owls.

Falcons are also part of the raptor family, a group of birds characterized by their hooked beaks, sharp talons and good eyesight, according to the U.S. Bureau of Land Management. Illinois is home to three kinds of falcons: American kestrels, merlins and peregrine falcons. Other falcons that reside in the United States include Aplomado falcons, gyrfalcons and prairie falcons.

Like all raptors, falcons are carnivores. The very things that make them falcons and raptors — their useful beaks and talons and keen eyesight — help them hunt for prey. Historically, humans have used falcons to help them hunt for small animals and birds, a practice called falconry, according to Smithsonian Magazine. Artistic depictions of falconry date back more than 3,500 years to ancient Mongolia and Mesopotamia. 

Falcons are mostly solitary species, living alone except to mate and nest. They generally mate with the same partner for life, the Smithsonian reports. They are also generally fast flyers, another skill that helps them hunt.

Read on to learn more about each of our three local falcon species.

American kestrel

We think of falcons as large, imposing birds, but not all are. American kestrels are the smallest falcon in North America, about the same size as a mourning dove, according to the Cornell Lab of Ornithology. They are generally between 8 inches and 12 inches long with a wingspan of between 20 inches and 24 inches. They only weigh between 3 ounces and 6 ounces. For comparison, consider that a hockey puck and a billiards ball each weigh about 5 ounces.

Kestrels are among the most colorful falcons. Males have blue-gray heads and wings, while females are more reddish brown, the Cornell Lab reports. Both males and females have lighter-colored breasts with dark barring on their wings and backs. They also have black striping on their faces.

These falcons are the most common of our three local species, and they live in Illinois year-round, IDNR reports. Kestrels from more northern regions do migrate south for winter, however. 

Kestrels mostly live in grasslands with little tree cover, and they often live near more populated areas, Cornell Lab reports. They are commonly seen perched up high on utility lines and poles, especially in agricultural areas. They nest in cavities but can't make their own, so they look for old woodpecker nests, nesting boxes, crevices in rocks and other structures, and nooks in buildings.

They mostly eat smaller prey like insects and small rodents, but they also sometimes eat lizards, frogs and snakes and are even capable of killing prey larger than themselves, like squirrels. They themselves can be preyed upon by larger raptors, including Cooper's hawks, sharp-shinned hawks, red-tailed hawks and barn owls, as well as some snake species. 

Merlin

Merlins are small falcons, but not as small as the American kestrel. Instead, they are closer in size to a crow, standing about 10 inches to 14 inches tall with a wingspan of about 2 feet. They typically weigh no more than about half a pound, according to the Cornell Lab or Ornithology.

Merlin falcons are dark in color, with males mostly a gray color and female and immature birds brown in color. They have heavily barred breasts, and their tails include narrow white bands on their dark-colored feathers.

In Illinois, we most often only see merlins during their migrations. In the spring, look for them in April and May as they pass through on their way to Canada and the farthest northern reaches of the United States, according to IDNR. They will begin making their return trip south as early as August. A small number of merlins may winter in Illinois, but usually farther south than Will County.

These falcons prefer forested areas, but during migrations they will make stopovers in grasslands and open forested areas. Recently they have become more common in towns and cities, sometimes nesting in residential areas, according to the Cornell Lab. They nest in trees, constructing their own or taking over an abandoned crow or hawk nest.

Merlins mostly eat small birds, commonly house sparrows, horned larks, dickcissels and small shorebirds, the Cornell Lab reports. They sit on high to scan for prey, then take off in chase. They will fly in pursuit until the prey tires out and they can easily snatch it. 

Peregrine falcon

The peregrine falcon is the largest and most impressive of our local falcon species. They are the largest falcon across most of North America — the gyrfalcon is larger but has a limited range — and they are powerful and swift flyers. They average speeds of between 25 mph and 35 mph but can fly as fast as about 70 mph while trying to catch prey, according to the Cornell Lab of Ornithology. When spotting prey from above, they can dive down at speeds of up to 200 mph, making it the fastest animal on Earth!

These falcons stand about 1 1/2 feet tall, and their wingspan is between about 3 feet and 3 1/2 feet wide. Their wings and backs are a steely blue-gray color, and their breasts are white with some dark-colored barring, according to the Cornell Lab. Despite their large size, they only weigh between about 1 pound and 3 1/2 pounds. 

Peregrine falcons are mostly migratory, and we only see them in much of Illinois — and the United States — as they travel back and forth between their breeding grounds in northern Canada and parts of the American West and their wintering grounds along the southern Atlantic and Pacific coasts. In Illinois they usually pass through each March and then again in August. Some of the falcons do also live in Illinois year-round, mostly around Lake Michigan, according to the Illinois Department of Natural Resources. 

Peregrine falcons have one of the largest natural ranges in the world, living on every continent except Antarctica. They can travel very long distances on their migrations, often from continent to continent. The word peregrine means "pilgrim" or "wanderer" and is a nod to their long-distance flight habits, according to the Cornell Lab. They can live in almost any open habitat. They typically nest in high cliffs or in buildings like silos, churches and skyscrapers. In places where they can't find a suitable cliff, they may move into a nest abandoned by large birds such as bald eagles or red-tailed hawks.

These falcons mostly eat birds, and they aren't particular about it. They have been known to eat more than 450 birds species in the United States alone, and they are capable of killing even very large birds, such as sandhill cranes, the Cornell Lab reports. They often sit high up on a perch scanning for prey then swoop down and snatch them from mid-air.

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Like bald eagles, peregrine falcons were threatened with extinction because of the use of the pesticide DDT, which interfered with the birds' ability to successfully nest because it weakened the shells of laid eggs, and it also poisoned adult birds, the Smithsonian reports. Since DDT was banned, the falcon population slowly recovered, and they were removed from the U.S. endangered species list in 1999.