Falco tinnunculuscommon kestrel

Geographic Range

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)

Habitat

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)

  • Range elevation
    0 to 5000 m
    0.00 to 16404.20 ft

Physical Description

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)

  • Sexual Dimorphism
  • female larger
  • sexes colored or patterned differently
  • Range mass
    150 to 190 g
    5.29 to 6.70 oz
  • Range length
    30 to 36 cm
    11.81 to 14.17 in
  • Range wingspan
    70 to 80 cm
    27.56 to 31.50 in

Reproduction

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)

  • Breeding interval
    Common kestrels breed once yearly.
  • Breeding season
    Common kestrels breed in April and May in the northern hemisphere.
  • Range eggs per season
    3 to 7
  • Range time to hatching
    26 to 34 days
  • Range fledging age
    27 to 32 days
  • Range time to independence
    7 to 8 weeks
  • Average age at sexual or reproductive maturity (female)
    1 years
  • Average age at sexual or reproductive maturity (male)
    1 years

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)

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • male
    • protecting
      • female
  • pre-independence
    • provisioning
      • male
      • female

Lifespan/Longevity

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)

Behavior

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)

  • Range territory size
    2 to 10 km^2
  • Average territory size
    5 km^2

Home Range

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)

Communication and Perception

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)

Food Habits

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)

  • Animal Foods
  • birds
  • mammals
  • amphibians
  • reptiles
  • insects
  • terrestrial non-insect arthropods

Predation

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)

Ecosystem Roles

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)

Economic Importance for Humans: Positive

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

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

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

Conservation Status

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

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Thomas Nelson (author), Kalamazoo College, Ann Fraser (editor, instructor), Kalamazoo College.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

chemical

uses smells or other chemicals to communicate

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

marsh

marshes are wetland areas often dominated by grasses and reeds.

migratory

makes seasonal movements between breeding and wintering grounds

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynous

having more than one female as a mate at one time

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

visual

uses sight to communicate

References

IUCN. 2004. "Falco tinnunculus" (On-line). The IUCN Red List of Threatened Species. Accessed October 07, 2006 at http://www.iucnredlist.org/search/details.php/49491/all.

Ali, S. 2006. "Common Kestrel" (On-line). Birding in India and South Asia. Accessed October 07, 2006 at http://www.birding.in/birds/Ciconiiformes/Falconidae/common_kestrel.htm.

Channing, K. 2006. "European Kestrel - Falco tinnunculus" (On-line). The Hawk Conservancy Trust. Accessed October 07, 2006 at http://www.hawk-conservancy.org/priors/kestrel.shtml.

Petty, S., D. Anderson, M. Davison, B. Little, T. Sherratt, C. Thomas, X. Lambin. 2003. The decline of Common Kestrels Falco tinnunculus in a forested area of northern England: the role of predation by Northern Goshawks Accipiter gentilis. Ibis, Volume 145 Issue 3: 472. Accessed October 07, 2006 at http://www.blackwell-synergy.com/doi/full/10.1046/j.1474-919X.2003.00191.x?cookieSet=1.

Shrubb, M. 1993. The Kestrel. London: Hamlyn.

Village, A. 1990. The Kestrel. London: T & A D Poyser Ltd.