American Kestrel Life History

Habitat

Habitat GrasslandsAmerican Kestrels favor open areas with short ground vegetation and sparse trees. You’ll find them in meadows, grasslands, deserts, parks, farm fields, cities, and suburbs. The southeastern U.S. form breeds in unusual longleaf pine sandhill habitat. When breeding, kestrels need access to at least a few trees or structures that provide appropriate nesting cavities. American Kestrels are attracted to many habitats modified by humans, including pastures and parkland, and are often found near areas of human activity including towns and cities. Back to top

Food

Food Small AnimalsAmerican Kestrels eat mostly insects and other invertebrates, as well as small rodents and birds. Common foods include grasshoppers, cicadas, beetles, and dragonflies; scorpions and spiders; butterflies and moths; voles, mice, shrews, bats, and small songbirds. American Kestrels also sometimes eat small snakes, lizards, and frogs. And some people have reported seeing American Kestrels take larger prey, including red squirrels and Northern Flickers. Back to top

Nesting

Nest Placement

Nest CavityAmerican Kestrels nest in cavities, although they lack the ability to excavate their own. They rely on old woodpecker holes, natural tree hollows, rock crevices, and nooks in buildings and other human-built structures. The male searches for possible nest cavities. When he’s found suitable candidates, he shows them to the female, who makes the final choice. Typically, nest sites are in trees along wood edges or in the middle of open ground. American Kestrels take readily to nest boxes (see Backyard Tips).

Nest Description

American Kestrels do not use nesting materials. If the cavity floor is composed of loose material, the female hollows out a shallow depression there.

Nesting Facts
Clutch Size:4-5 eggs
Number of Broods:1-2 broods
Egg Length:1.2-1.5 in (3-3.8 cm)
Egg Width:0.9-1.1 in (2.4-2.8 cm)
Incubation Period:26-32 days
Nestling Period:28-31 days
Egg Description:White to yellowish or light reddish-brown, mottled with violet-magenta, gray, or brown.
Condition at Hatching:Feeble, with sparse white down over pinkish skin; eyes partially open by first or second day.
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Behavior

Behavior Aerial Dive (ground/talons)American Kestrels normally hunt by day. You may see a kestrel scanning for prey from the same perch all day long—or changing perches every few minutes. A kestrel pounces on its prey, seizing it with one or both feet; the bird may finish off a small meal right there on the ground, or carry larger prey back to a perch. During breeding season, males advertise their territory by repeatedly climbing and then diving, uttering a short series of klee! calls at the top of each ascent. Courting pairs may exchange gifts of food; usually the male feeds the female. Early in the pairing-up process, groups of four or five birds may congregate. You may see American Kestrels harassing larger hawks and eagles during migration, and attacking hawks in their territories during breeding season. Kestrels compete over the limited supply of nesting cavities with other cavity-nesters, and sometimes successfully fight off or evict bluebirds, Northern Flickers, small squirrels, and other competitors from their chosen sites. Back to top

Conservation

Conservation Low ConcernThe American Kestrel is the continent’s most common and widespread falcon but populations declined by about 50% between 1966 and 2015, according to the North American Breeding Bird Survey. Partners in Flight estimates the global breeding population at 4 million, with 39% spending some part of the year in the U.S., 10% in Mexico, and 13% breeding in Canada. They rate an 11 out of 20 on the Continental Concern Score and are not on the 2016 State of North America's Birds' Watch List. Current declines stem from continued clearing of land and felling of the standing dead trees these birds depend on for their nest sites. The American Kestrel is also losing prey sources and nesting cavities to so-called “clean” farming practices, which remove hedgerows, trees, and brush. An additional threat is exposure to pesticides and other pollutants, which can reduce clutch sizes and hatching success. For kestrels in North America, a larger problem with pesticides is that they destroy the insects, spiders, and other prey on which the birds depend.Back to top

Backyard Tips

Consider putting up a nest box to attract a breeding pair. Make sure you put it up well before breeding season. Attach a guard to keep predators from raiding eggs and young. Find out more about nest boxes on our Attract Birds pages. You'll find plans for building a nest box of the appropriate size on our All About Birdhouses site.

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Credits

Dunne, P. (2006). Pete Dunne's essential field guide companion. Houghton Mifflin Harcourt, New York, USA.

Lutmerding, J. A. and A. S. Love. Longevity records of North American birds. Version 2015.2. Patuxent Wildlife Research Center, Bird Banding Laboratory 2015.

Partners in Flight (2017). Avian Conservation Assessment Database. 2017.

Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski, Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2017). The North American Breeding Bird Survey, Results and Analysis 1966–2015. Version 2.07.2017. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.

Sibley, D. A. (2014). The Sibley guide to birds, second edition. Alfred A. Knopf, New York, USA.

Smallwood, John A. and David M. Bird. 2002. American Kestrel (Falco sparverius), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.

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