Falco tinnunculus
common kestrel

Falco tinnunculus is a widespread kestrel species, found throughout Europe, Asia, and Africa. Its range spans from Great Britain to China and as far south as South Africa. In Europe, F. tinnunculus is migratory and winters in southern Europe and sub-saharan Africa. However, the majority of the breeding population in Europe is non-migratory. ("Falco tinnunculus", 2004; Village, 1990)

Common kestrels prefer open, grassy fields and farmlands, which give them sufficient open areas to hunt. They can sometimes be found in forested areas and marshlands. Common kestrels occupy a wide range of altitudes, from sea level to almost 5000 m. (Channing, 2006; Shrubb, 1993; Village, 1990)

Falco tinnunculus is among the smallest of all raptors. Adults range in weight from 150 to 190 g, with females tending to be larger than males. Common kestrels have longer tails and wingspans relative to their body size than most other falcons, which allow them to be easily distinguished from related species. Common kestrel plumage ranges from gray to brown. The back is usually a darker color than the breast, both are covered in dark brown or black spots. The wings are tipped in black on the dorsal side and are pale underneath. Males often have a more bluish-gray heads and tails. Females are more of a reddish-brown color and have barring on the tail. In both sexes, there is a darker stripe or spot underneath each eye. (Channing, 2006; Village, 1990)

Hatchlings are mostly white or very pale brown. Older juveniles have feather patterns similar to adults, but the feathers are noticeably less sleek in juveniles and down is clearly visible. Juveniles more closely resemble adult females than adult males. (Channing, 2006; Village, 1990)

Common kestrels become quite vocal during the mating season, displaying a variety of calls. However, most of the calls are used year-round and the birds merely become more talkative during courtship months. One call, described as sounding like "quirrr-rr quirrr-rr," is made by both sexes during mating behaviors and by the female when she becomes interested in mating. A common visual display is a slow, "shivering" flight in which both sexes beat their wings quickly but shallowly. It may look like only the tips of their wings are beating. This display usually takes place immediately before or after mating. Vocal calls, such as the "quirrr-rr" call, accompany this display, signaling excitement between the pair. Mating pairs are often seen flying quickly together at great heights. This flight is characterized by sharp wing beats and a slight rocking motion. The end of this display is sometimes marked by the pair diving dramatically to the nest with wings thrown into a sharp "V" shape. (Shrubb, 1993; Village, 1990)

From the beginning of courtship until egg-laying, males hunt for the females and brings them prey as gifts. During this time, females becomes increasingly sedentary and spend the majority of their time in the nest. (Shrubb, 1993; Village, 1990)

Breeding density is most affected by available resources, such as nesting sites and food. (Village, 1990)

Common kestrels normally form pair bonds for long periods of time, if not for life. Rarely, males have multiple mates. This occurs in 1% to 2% of birds in some studies. (Village, 1990)

Common kestrel breeding and courtship behaviors begin in February or March. The breeding cycle ends about a month after fledging, which occurs in late August. Breeding occurs in April and May in the northern hemisphere. (Shrubb, 1993; Village, 1990)

Common kestrels nest on ledges, in buildings, in trees, or use abandoned nests of other bird species. They do not make their own nests, but may rearrange materials already present in the nesting site. A clutch consists of 3 to 7 eggs which hatch in 26 to 34 days. Fledging normally occurs within the first month after hatching, but young are still dependent on their parents until hunting skills are sufficient, which takes about 7 or 8 weeks. The young will reach sexual maturity by the next breeding season but most common kestrels do not mate during their first year of maturity. (Shrubb, 1993; Village, 1990)

Both sexes help in raising young. Females are sole incubators of the eggs. Hatchlings are altricial when they hatch, but grow very quickly and must be fed frequently. Males usually catch food for hatchlings while females tend to them. After fledging, young are dependent on their parents for food for the next month, since hunting and flying skills are slower to develop. (Ali, 2006; Village, 1990)

There is little data on the lifespan of F. tunnunculus in the wild. Predation, pollution, resource limitation, and road accidents contribute to early mortality in this species. Only about 66 % of common kestrels survive their first two years in the wild. (Shrubb, 1993; Village, 1990)

Common kestrels are diurnal hunters and spend most of their time perching and resting within their home range. They normally spend large amounts of time in flight only when hunting or during courtship behaviors. Predominantly solitary animals, common kestrels are usually seen alone. Pairs can be seen during the breeding season. Nonbreeding birds migrate short distances to summer and winter ranges. (Shrubb, 1993; Village, 1990)

Common kestrel home ranges are dependent on available resources. Nesting sites are always within the home range but are not necessarily the center of the range. Common kestrels may use areas of their home ranges unequally, depending on food abundance and perching sites. (Shrubb, 1993; Village, 1990)

Common kestrels primarily communicate visually and acoustically. Given their solitary nature, most of these communications are limited to the mating season (see 'Reproduction: Mating Systems'). An alarm call, described as "kee-kee-kee," is heard from a member of the pair when young are threatened. Territorial displays, however, occur year-round. (Village, 1990; Shrubb, 1993; Village, 1990)

When territory is threatened, common kestrels may fly under the intruder while fanning their tails, shivering (see 'Mating Systems') and slowly rising under the intruding bird. Sometimes, the defending bird will attack the intruder. (Shrubb, 1993)

Common kestrels perceive their environment mainly by sight since hunting from the air is a predominantly visual behavior. They have also been observed on foot, hunting by sound and sight. (Shrubb, 1993)

Common kestrels feed primarily on small mammals, including voles (Arvicolinae) and mice (e.g. Apodemus sylvaticus). They sometimes feed on amphibians, reptiles and other birds. Common kestrels hunt by soaring 10 to 20 m above the ground and diving quickly onto their prey. They may also been seen hunting on foot for small mammals and insects, especially beetles and grasshoppers. If prey is abundant, common kestrels will sometimes kill more than they need and cache what they do not eat. (Shrubb, 1993; Village, 1990)

Common kestrels are not typically preyed on, but are taken occasionally, especially as fledglings. Goshawks (Accipiter gentilis) are known to prey on common kestrels. Suspected common kestrel predators include peregrine falcons (Falco peregrinus), sparrowhawks (Accipiter nisus), eagle owls (Bubo bubo) and tawny owls (Strix aluco). (Petty, et al., 2003; Village, 1990)

In some areas, common kestrels are key predators of small, herbivorous mammals, including voles and mice, and help control rodent and small mammal populations. Although they fall prey to goshawks and other raptors, they are not a primary food source for raptors. (Channing, 2006; Shrubb, 1993)

Common kestrels are important in controlling agricultural pests, especially mice and voles. They are also used in falconry. (Channing, 2006)

There are no known adverse effects of common kestrels on humans.

This species is evaluated as of "least concern" by the IUCN.