American Kestrel (Falco sparverius)

American Kestrel

Subspecies

Monotypic species

Genus

Members of the genus falco are mostly medium-sized falcons, but vary from the large peregrine falcon to the small American kestrel. The wings are long and pointed and used almost continuously during flight. The bill is short, powerful, and with a distinct ‘tooth’ on each side. Most falcons of this group have a black teardrop-shaped ‘mustache’ mark on each side of the head. Falcons are fastflying birds of open country and are famous for attaining high speeds as they dive from high altitudes to knock birds out of the air.

Physical charateristics

The American Kestrel is a raptor with strongly sexually dimorphic plumage. It is the smallest and most delicate-looking of the American falcons, with long wings and a long tail. Its head is blue, brown, and white. Males are brightly colored, with reddish-brown backs, slate-blue wings streaked with black, and tan breasts with black spots. The male’s head is blue and brown, and both sexes have bold, black eyespots at the napes of their necks. Females are brown streaked with black on the back, and white streaked with brown on the breast. The female has multiple bands on her tail. Both sexes have two bold, vertical face stripes.

Listen to the sound of American Kestrel

[audio:http://www.planetofbirds.com/MASTER/FALCONIFORMES/Falconidae/sounds/American Kestrel.mp3]

Copyright remark: Most sounds derived from xeno-canto

recorded by A. Bennett Hennessey

wingspan min.:	50	cm	wingspan max.:	60	cm
size min.:	19	cm	size max.:	21	cm
incubation min.:	29	days	incubation max.:	30	days
fledging min.:	30	days	fledging max.:	30	days
broods:	1		eggs min.:	3
			eggs max.:	7

Range

North America, Latin America : widespread

Habitat

The American kestrel nests in tree cavities, woodpecker holes, crevices of buildings, holes in banks, nest boxes or, rarely, old nests of other birds. The American kestrel is highly adaptable behaviorly and lives just about everywhere, as long as there is some open ground for hunting and conspicuous places on which to perch (e.g., telephone wires).

Reproduction

For up to six weeks before egg laying, females are promiscuous, mating with two or three males. Once a female settles with one mate, the pair mate frequently until egg laying. Three to seven eggs are laid (usually 4 or 5) over a period of 2 or 3 days. The female does most of the incubation, but males have been known to occasionally sit. Both sexes have brooding patches. Incubation lasts 29 – 30 days and hatched chicks are non-competitive. Once chicks have hatched, females beg food from males. The female, in turn, feeds the young for the first 20 days. After that period, chicks beg for food from males and feed themselves. After 30 days, chicks leave the nest. The family remains as a unit for some time. The survival rate of chicks is about 50% under natural conditions, but it is usually higher under better conditions.

Feeding habits

In the summer, American kestrels hunt in the early morning and evening, eating large insects (mainly grasshoppers). During winter, they hunt throughout daylight hours and eat small mammals (mice and sparrow-sized birds), sandpiper chicks, lizards, scorpions and amphibians.

Video American Kestrel

httpv://www.youtube.com/watch?v=Z3-CpMhmi44

Conservation

This species has a large range, with an estimated global Extent of Occurrence of 25,000,000 km2. It has a large global population estimated to be at least 4,000,000 individuals (Ferguson-Lees et al. 2001). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.
The American kestrel permanently inhabits (without seasonal migration) North and South America from near the tree-line in Alaska and Canada and south to Tierra del Fuego. The bird can also be found in the West Indies, the Juan Fernandez Islands and Chile. It is largely absent from heavily forested areas, including Amazonia.

Migration

Resident or sedentary over most of range. Race sparverius, from Alaska, Canada and N USA, moves S in winter: complex situation, but leap-frog migration suggested; birds from farthest N are longer range migrants; some birds move c. 2700 km, occurring S to at least Panama. Movement over water also occurs with birds from North America moving to Caribbean islands. Males tend to winter farther from areas than females. Vagrant to Falkland Is, with some birds overwintering.

Distribution map

American Kestrel distribution range map

Literature

Title Sex-related differences in habitat selection in wintering American kestrels,
Falco sparverius

Author(s): DANIEL R. ARDIA and KEITH L. BILDSTEIN

Abstract: The American kestrel, Falco sparverius, has sex-re..[more]..

Source: Anim. Behav., 1997, 53, 1305-1311

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