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American Kestrel EC 1578 December 2005 J. Jones and S. Sells Do you want to print a copy? We recommend downloading the print version (266 KB). First download the free Adobe Reader, if you don't already have it. Contents Species description Where they live and why Creating habitat Fun facts Did you know that the American kestrel is the smallest falcon in North America and the second smallest falcon in the world? The average length of the American kestrel is 9 to 12 inches, about the size of a robin. A falcon is a bird of prey, or raptor, which in Latin means “to seize.” Raptors have very good eyesight, a hooked beak, and eight very sharp talons, all of which help them hunt and catch their prey. Kestrels are one of the most abundant raptors in North America, so it should be easy to attract them to your area. Kestrels live near open fields and meadows. They hunt in open areas and find shelter in nearby trees. They are found throughout North, South, and Central America. Kestrels have some interesting antics that make them easy to identify. Look for kestrels on telephone wires along open fields. If a robin-size bird is bobbing its head and pumping its tail, it might be a kestrel. Their calls sound like a shrill “killy killy killy.” Species description Kestrels feed mainly on insects, such as grasshoppers, beetles, and crickets, but they also eat small mammals and songbirds. They used to be called sparrow hawks because they are known to feed on small birds such as sparrows. Kestrels find their prey either by sitting on a perch and then darting out or by hovering. To hover, they flap their wings in a way that keeps them in the same place. After a kestrel has spotted its prey, it does what is called a stoop: it pulls in its wings and dives to seize its prey. Kestrels have been clocked at 60 miles per hour while pursuing prey. Male kestrels are more colorful than females. Males have slate blue on their wings and a rusty red back and breast. Females do not have slate blue wings, but instead have the rusty red color along their back and wings. Female tail feathers are barred, meaning the tail is striped with black and rust color. Both sexes have a white face with a double set of black vertical stripes. The head is slate blue with a small rusty red patch on top, which is more visible on the male. American kestrels can see in the ultraviolet light range. Although humans see a wide range of colors, there are many colors we can’t see. Other animals can see different ranges of colors. Because American kestrels can see what we call “ultraviolet” light, the world looks bluer to them. Why do they see in blue? Wildlife biologists believe the main reason is to help them hunt for rodents. Like all animals, rodents leave urine marks, often near the burrows where they live. Humans can’t see the urine marks, but to a kestrel’s eyes the urine looks bright because it reflects ultraviolet light. Can you guess how this might help a hungry kestrel? The bird focuses his eyes on the bright trail near a rodent burrow and waits for the rodent to return. When the kestrel sees it, he dives and snatches up the rodent for a meal. Females usually lay four or five pinkish-white eggs with brown or lavender markings, although some eggs are white with no markings. The eggs usually are less than 1.5 inches long. Both parents usually take turns incubating (sitting on) the eggs for about 30 days until the chicks hatch. The newly hatched chicks have downy feathers and closed eyes. They are immobile and must be fed by their parents. After about 21/2 weeks, they reach adult size. They fledge (leave the nest) after about a month. Where they live and why Kestrels live wherever there are open fields and meadows such as parks, suburbs, forest edges, deserts, and low alpine habitats. During the winter, American kestrels must find a place that is warm with enough prey. There are two types of migration a kestrel may do: altitudinal and latitudinal. In altitudinal migration, kestrels come down to a lower elevation, where there is no snow and prey is more abundant. Other kestrels migrate latitudinally to a warmer area farther south. American kestrels are one of the few North American falcons that are cavity nesters, meaning they nest in tree holes. They are secondary cavity nesters, which means they don’t make their own holes. Instead, they use holes that other birds (including woodpeckers) have made. An old woodpecker nest is a great place for a kestrel pair to raise its young. If your area has old trees, you may have kestrels, because cavities are more common in older trees. Creating habitat If your area doesn’t have old trees, putting up nest boxes may attract kestrels to the area. A schoolyard with a lot of grass and trees is a great place for a kestrel nest box. Natural habitat is always best. To attract a breeding pair of kestrels, the nest box needs to be installed by early February at the latest, when kestrels usually start finding mates. For information on how to build a nest box, try searching for “nest boxes for American kestrels” online. Many websites have directions for setting up a good nesting site for kestrels. Put the nest box in a low-traffic area, away from loud human activity such as car traffic. Nail the box to a tree, post, or side of a building. It is helpful to place the box where there is a patch of trees with good perches, but also plenty of open area for hunting. Don’t place the box in direct sun or extreme weather. The box needs to be 20 to 30 feet from the ground so that predators can’t get to the eggs. It's also a good idea to place a predator guard under the nest box. You can make a predator guard by wrapping a downward-cup-shaped piece of metal around the tree trunk about 2 feet below the box. Clean out the box at the end of summer after you are certain the kestrels are done nesting and the hatchlings have fledged. Clean it again in late winter before the adults nest. Kestrels do not make a nest inside of the box, but boxes do get messy because of shells and food scraps. Do not use chemicals to clean out the box; use a weak vinegar solution and a scrub brush. Fun facts American kestrels are the smallest of the North American falcons. Kestrels are also referred to as sparrow hawks. They are cavity nesters. Young kestrels learn to hunt by hunting in family groups. The world looks bluish to kestrels because they can see ultraviolet light. Kestrels can fly 60 miles per hour when pursuing prey. Prepared by Jenelle Jones and Sarah Sells, students in Fisheries and Wildlife, Oregon State University. Photos by: Noah Stryker, USGS Patuxent Wildlife Research Center, Dave Merke U.S. Fish and Wildlife Service Published December 2005

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