American Kestrel Fact File
The American kestrel is the smallest species of falcon in North America. Adults reach a total length of 27cm (10.5in).
These birds are opportunistic carnivores. They are often seen hovering at the road side where they will hunt for food. These include insects, birds and reptiles.
Nesting takes place in a tree hollow. The removal of these represents one of the largest threats for these birds but they are considered least concern by the IUCN.
They have an ability to see ultraviolet light frequencies which can not been seen by other animals.
Read on to learn more about these brilliant birds.
Male and female American falcons exhibit marked sexual dimorphism with major differences in their appearance. They are one of only three American raptors to exhibit this trait.
The male is colored reddish-brown across the back with slate-blue wings and a tan breast with black spots patterning this.
Females feature brown streaks across the back and a breast colored white with brown streaks. Across her tail are multiple bands.
Both male and female feature two black, vertical stripes on either side of the face.
On the back of the head are two eyespots which help to prevent attacks by predators. When in flight it appears as if they are looking up at aerial predators helping to stop them attacking and allowing the kestrel to focus on hunting.
As the smallest species of kestrel in North America the reach a length of 27cm (10.5in) long with a weight of 85-170g (3-6oz). Their wings have a span of 51 to 61cm (20 to 24in) across.
Females are regularly as much as 15% bigger than males.
American kestrels are carnivores. They feed on a range of insects and small vertebrates including reptiles, mammals and birds. Their diet is subject to seasonal variations.
They are considered an opportunistic hunter which will target any prey which is readily available.
Kestrels are known for their hovering flight. They will wait above an area until prey comes in to view and then dive down to seize it. Most food is taken from the ground but some may be caught while in flight.
American kestrels have a wide range covering parts of North, Central and South America. They occur in the following countries – Anguilla; Antigua and Barbuda; Argentina; Aruba; Bahamas; Barbados; Bermuda; Belize; Bolivia; Bonaire, Sint Eustatius and Saba; Brazil; Canada; Cayman Islands; Chile; Colombia; Costa Rica; Cuba; Denmark; Dominica; Dominican Republic; Ecuador; El Salvador; Estonia; Falkland Islands; French Guiana; Guadeloupe; Guatemala; Grenada; Guyana; Haiti; Honduras; Jamaica; Malta; Martinique; Mexico; Montserrat; Nicaragua; Panama; Paraguay; Peru; Puerto Rico; Portugal; Saint Kitts and Nevis; Saint Lucia; Saint Martin; Saint Pierre and Miquelon; Saint Vincent and the Grenadines; Sint Maarten; South Georgia and the South Sandwich Islands; Trinidad and Tobago; Turks and Caicos Islands; Venezuela; United Kingdom; United States; Uruguay; British Virgin Islands and the U.S. Virgin Islands.
Their wide range is a result of their ability to inhabit a wide variety of habitats. These include forest, savanna, desert, woodland, grassland and shrubland.
They are commonly sighted along roadsides hovering for food.
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Breeding season is variable across their wide range taking place from March to June.
Pairs form after a courtship display in which the female hovers slowly and the male will perform high flights before diving back to the ground. Before the female lays her eggs she may mate with multiple mates.
Once pairs form they are generally considered monogamous and they will remain with their partner for multiple years.
The nest is constructed inside the hollow of a tree. They will make use of nest boxes provided by humans if natural habitat is unavailable. In some cases they have nested in abandoned magpie nests or hollows in a cactus.
In to their nest they deposit 3-4 eggs which are incubated for a total of 28 to 31 days. Both parents will assist with the incubation. The eggs are colored white or pale brown.
After hatching the female will provide most of the care at the nest while the male goes out to collect food. After 1-2 weeks the female will begin to join these foraging trips.
Fledging occurs between 28 and 31 days old after which the chicks are supported by their parents for a further 12 days. After fledging the young may join young from other nests in a group.
Their eyesight is so good that they can spot prey while hovering up to 30m (90ft) away from it.
Outside of the breeding season the American kestrel will be solitary.
Predators and Threats
The population of the American kestrel is currently thought to be stable with a wide range and large population helping to ensure their safety long in to the future.
A major threat to the survival of the American kestrel is the removal of the tree hollows which humans remove. Humans may help to slow this decline through providing an artificial nest site such as a nest box.
Small declines are seen in Northern areas of their range but conservation efforts such as the provision of nestboxes has helped to slow this.
Kestrels are able to see ultraviolet light, these colors are not visible to humans. This allows them to see the urine trail of a rodent which helps point them in the direction of the rodents.
These birds are the smallest kestrel species in North America.
American kestrels may also be known as the sparrow hawk.
Jackson, T.,2011. The Illustrated Encyclopedia of Animals, Birds & Fish of North America. 1st ed. Leicestershire: Lorenz Books
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