Our Urban Forrest: This American Kestrel

The recent discovery of a bald eagle nest within the city limits, the first one sighted since the 1880s, points to the success of the ban on DDT and protection granted by the Federal and State laws. But it also reveals how, if given a chance, nature will fill in the niches of our built environment.

A male American Kestrel (with a broken wing) rescued by the Northern Illinois Raptor Center

In our downtown canyons, Falcons swoop down upon their unsuspecting prey, striking in mid-flight and creating a pyrotechnics display of feathers worthy of the 4th. Near our parks and forest preserves, Red-tailed and Cooper's hawks lazily chase frantically arcing flocks of rock pigeons, patiently watching for the least among them to tire and drop from formation. Small, ground-hugging rodents in an open ball field will never know what hit them if a raptor decides it's mealtime.

Predator birds like being high up and that's where they usually build their nests. Falcons nest on the precipices of tall building, bald eagles in tall, stout trees near water and our Red-tailed and Cooper's hawks in the tallest trees in local parks. But deep in the neighborhoods of this city, in a tree or atop a building near you, lives one of the smallest

Female Kestrel

birds of prey in these here parts: Falco sparverius, the American Kestrel.

The smallest member of the falcon family, the American Kestrel is no larger than a robin. Females are cinnamon with barred wings and tail. Males have bluish-gray wings and a solid cinnamon tail with a single dark band at the tip. Both have two vertical black facial stripes on each side of the head.

Like other members of the falcon family, the Kestrels European cousins were used in falconry but were generally relegated as a trainer bird for children who needed to work their way up to a full sized Peregrine. Because of their small size Kestrels are the most difficult of the falcons to keep in captivity and usually have to be weighed, along with their food, on a daily basis to ensure their weight stays within a very narrow range.

3 male Kestrels, possibly siblings

Out in the wild, and now we're talking about my Logan Square backyard, Kestrels prey on anything that's living and small enough to catch. This includes large insects, small birds and rodents and the adolescents of larger birds and rodents. Like other raptors Kestrels will hunt from a perch like a power line or on the wing, hovering in mid-air. You always know if a Kestrel has made a kill because it lets out a series of short, rapid screeches: klee-klee-klee-klee! Actually, they tend to screech at the slightest prompting: seeing a fellow Kestrel, a major change in weather, dawn, dusk. Whenever I hear that screech I rush outside to see what's up. More often than not, it's a kill. I've seen my Kestrels sitting high in the neighbor's tree ripping away, at different times, gray fur, downy feathers, butterfly wings and bloody red meat.

Kestrels live in most of the Americas and will nest in Chicago. Although they are solitary birds they will form a mating pair for the breeding season with the male aiding with the feeding. They don't build their own nests but rely on either finding an empty nest or forcibly harassing other birds out of theirs. Kestrels will take to a nesting box that's high and away from human noise and activity. My Kestrels always fly west in the evening and I think their nest is somewhere in the factory district west of Pulaski.

Our Chicago Kestrels are true snow-birds, following the warmer weather and their more readily available prey south and returning in the early spring. With robins, of late, wintering in Chicago (heck, robins now breed north of the Arctic circle), I no longer consider them the harbingers of spring. Instead I listen for that distinctive klee-klee-klee-klee! to let me know that winter is finally over.

Photo montage: Drama in the neighbor's maple tree.

On a mid-summer evening, a male Kestrel nears the nest of a Jay, most likely to make off with one of the Robin's chicks

Noisily defending its nest the Robin feigns an attack...

...and lands on the opposite end of the Kestrel's branch (left of frame) forcing the Kestrel to turn its back on the Robin's nest

After an hour or so of this harassment the Kestrel gives up and takes off...

...escorted by the Robin...

...to the nearest TV antenna

The Robin takes a breather unaware that she’ll probably have to go through the same ordeal tomorrow

For more information: Northern Illinois Raptor Center ; Kestrel info including audio clip