American Kestrel – Falco sparverius
“America’s smallest and most colorful falcon”
The American kestrel has a small body, about the size of a blue jay, with a longish tail. They are known for being colorful and can be identified by their reddish-brown bodies and dark tail stripes. They measure roughly 12 inches in length and have a 20 to 24-inch wingspan. Kestrels are one of three raptor species in North America that are sexually dimorphic. Males can be easily identified by their distinctive blue head and wings, and a single broad black band across the tip of their tail feathers. Females are slightly larger than males, and rufous with black barring all over the top and tail. Both males and females adorn the characteristic black double mustache on their faces. Females and juveniles are nearly identical and can be difficult to tell apart.
Kestrels can be found in a wide variety of habitats including coastlines, farmland, grasslands, and even deserts. Their preferred type of habitat is open areas with raised perches, for hunting and raising young. However, they have been known to inhabit human-altered environments, and are most often spotted on roadsides.
The kestrel diet mostly consists of insects, but they have been known to consume small rodents, reptiles, amphibians, and other small birds. When searching for food, kestrels can often be seen “hover-hunting” several feet above the ground when there are no available perches nearby.
Many kestrels found in the southern US are permanent residents, but birds located in the northern US migrate to the far south for the winter months. Females arrive at the wintering areas first and claim the more preferred open areas. Males arrive later and are forced to overwinter in areas with more trees.
Kestrels are considered secondary cavity nesters that utilize existing nests or man-made structures to raise their young. Since they do not excavate their own nesting sites, Tree snags, and nesting boxes are common nesting areas. The availability of pre-made cavities limits the ability for the population to grow, which is why providing nesting boxes is an important step in conserving the species.
TN: Common, but populations are generally decreasing statewide
US: Low concern (population = 9,200,000, decreasing at a rate of 1.4% /year rangewide)
IUCN Conservation Status: Least Concern
USFWS: The southeastern subspecies, Falco sparverius paulus, is a Bird of Conservation Concern for Bird Conservation Regions (BCR) 25 (West Gulf Coastal Plain/Ouachitas), 27 (Southeastern Coastal Plain), and 31 (Peninsular Florida).
North American distribution of the American Kestrel (courtesy of Cornell Lab of Ornithology)
The American kestrel has a flat and simple call pattern that sounds most similar to “Shrill killy-killy-killy” and is used by both males and females for defense, courtship, and communication.
- https://www.hawkmountain.org/raptors/american-kestrel
- https://www.allaboutbirds.org/guide/American_Kestrel/overview
- https://nestwatch.org/learn/focal-species/american-kestrel/
- https://www.allaboutbirds.org/guide/American_Kestrel/id
- https://www.audubon.org/field-guide/bird/american-kestrel
- https://avianreport.com/american-kestrel-calls-sounds/
- https://avianreport.com/female-american-kestrel/