Lesser Kestrel

Maximum longevity: 10.9 years (wild) Observations: Oldest bird in banding studies was 10.9 years of age (http://www.euring.org/data_and_codes/longevity.htm).

Perception Channels: visual ; tactile ; acoustic ; chemical

This small falcon has a length of 30-36 cm with long pointed wings. The long tail has a broad black terminal band. This falcon has strong sexual dimorphism in its plumage. Males have a chestnut back and a blue-grey crown, neck, rump, and tail. Their belly is a creamy pink with small brown streaks. The eye ring is bright yellow while the feet are an orange-yellow. The undersides of the wings are white with a black tip. Females have a brown back and head with a pale belly. Both the back and belly are streaked with brown. The wings are also light with dark barring and black tips. Juvenile lesser kestrels look similar to the females.

Other Physical Features: endothermic ; bilateral symmetry

Average lifespan
Status: wild: 6.2 years.

Lesser kestrels are found in bushed, wooded, and open grassland and cultivation. They nest on mountain slopes, gorges, deep ravines, and other rocky terrain, all of which must have open areas around them for the birds to hunt. They are found most numerously in highland farming regions and on grassy plains during the winter range.

Terrestrial Biomes: desert or dune ; savanna or grassland ; forest ; scrub forest

The lesser kestrel breeds in the palearctic in Europe and northern Asia roughly between 30 and 50 degrees North latitude. The distribution includes altitudes of up to 500m above sea level. It is a migratory species, spending its winter in Africa, south of the Sahara. From February to April this bird is most numerous in northern Tanzania and southern Kenya.

Biogeographic Regions: palearctic (Native ); ethiopian (Native )

Kestrels are carnivorous, feeding on small mammals, especially voles, however they are very adaptable to other prey selections. They will eat almost anything they can kill. Their selected prey is either the most abundant or most easily caught of the area. Other prey examples are young rabbits, birds, small bats, lizards, snakes, frogs, insects, earthworms, fish, and crabs. Kestrels can change their hunting style depending on the kind of prey, weather conditions, and their energy requirements. These predators take full advantage of their keen eyesight, sharp claws, and strong beak. They hunt from a perch or from the air. The vertebrate prey is pounced on from a rapid dive, then grabbed by the claws and killed by a bite to the base of the skull. Attacks on less active prey results from slow shallow dives where the kestrel lands and takes the prey directly into its beak.

This bird eats mice and insects that damage human crops.

There still is not complete data on the distribution of the lesser kestrel. This information is needed in order to adequately conserve the species. Important subjects to study include problems with the foraging habitat, pesticide contamination affecting reproduction success and food availability, problems with breeding colonies, winter ecology and how to develop and coordinate an international conservation strategy. The winter distribution seems to be the most unknown.

Trends in the breeding populations of the lesser kestrel clearly show this species is seriously threatened worldwide. This bird is protected by law, but not all of the breeding sites are in protected areas. Legal protection of all sites is necessary for conservation because most of the causes of death are hunting or taking young from the nests.

Estimations of the abundance of the lesser kestrel show that breeding numbers have dropped by 95% since the 1950's. Sharp declines are especially obvious in its European range. A marked decrease in breeding range appeared all over Europe, most notably in Poland, Czechoslovakia, and Austria where lesser kestrels are no longer breeding.

IUCN Red List of Threatened Species: vulnerable

Besides hunting, pesticides and predation are other causes of death in lesser kestrel populations.

Breeding occurs during the months of March through June. Kestrels do not build nests. Instead they lay their eggs in a depression they scrape in the trees of the nesting location. They breed in colonies of up to 100 pairs. Females invest more time in nesting activities than males. Kestrels have a normal clutch size of 4 to 6, laid over a two day interval, but the range in number of eggs is 1 to 7. Incubation starts after the third egg is laid and lasts 28 to 31 days. Because incubation is delayed until the after the third egg, the first three eggs usually hatch on the same day with the rest following in the next couple of days. This means the last bird hatched is smaller than the rest. The difference in size allows the brood to be reduced by sibling rivalry if sources of food are short. Kestrel nestlings have been seen to kill and eat brood-mates, but most deaths occur because of failure to compete for food. Parents continue to feed their young for 2 to 4 weeks after hatching.

Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous

Travelling in loose flocks of hundreds of birds, this sociable species will also roost together in trees, but migrate singly or in flocks of less than 50, at altitudes of around 2000 m. The lesser kestrel's flapping flight is shallow and rapid and is more conspicuous to prey than the subtle gliding flight that is more normally used. Hunting, usually for small mammals, makes excellent use of the lesser kestrel's powerful eyesight, sharp claws and strong beak. It dives almost silently from a perch or from mid air and pounces on prey with the claws, before swiftly killing its prey with a bite to the back of the head (2). Breeding takes place between March and May, and eggs are laid, not in nests, but in scraped out depressions in trees. Again, lesser kestrels nest as colonies and pairs will display to each other to strengthen the pair bond. The female invests more time than the male in incubating the four to six eggs she lays, and rearing the chicks when they hatch after 28 – 31 days, but the male will contribute by fighting to defend their territory. The chicks hatch over several days and so the last to hatch is smaller than the others. This individual is most likely to die as it cannot compete effectively for food, and when food is particularly scarce it may be killed and eaten by its siblings. The chicks are fed for two to four weeks, and then must learn to hunt for themselves (2).

The lesser kestrel is protected by law, but its breeding sites are not, and numbers of breeding birds have dropped by 95% since the 1950s (2). Research and management of the species and its habitat have been carried out in several countries and both a European and an International Action Plan have been implemented. These encourage surveying and monitoring, the construction of artificial nests, and research into factors limiting the kestrel's survival and habitat management. The most immediate priority is to enforce the legal protection already in place (6).

The lesser kestrel is a small kestrel with long pointed wings and a long tail marked with a black band at the end. Males and females are distinguishable by colouring. Males have a pale brown back and blue-grey feathers on the crown, rump, neck and tail. The belly is creamy pink with small brown streaks. In females, the back and head are mid brown and the belly is pale. Both back and belly are streaked with brown. Males and females have white undersides to their wings, with black tips (2). The eye ring is bright yellow and the feet are yellow to orange. The ankles and feet lack feathers (5).

An inhabitant of highland farming regions and grassy plains in the winter range, the lesser kestrel prefers open or wooded grassland and cultivated areas during the summer breeding season. It nests in areas with mountain slopes, gorges and deep ravines surrounded by open areas for hunting (2).

Found in Europe and northern Asia between latitudes of 30 and 50 º N at up to 500 m above sea level. This species is migratory, moving to sub-Saharan Africa during the winter, and congregating most abundantly in northern Tanzania and southern Kenya (1).

The lesser kestrel is classified as Vulnerable (VU A2bce + 3bce) on the IUCN Red List 2004 (1) and is listed on Appendix II of CITES (3). It is also listed on Appendices I and II of the Convention on Migratory Species (4).

The main cause of decline of the lesser kestrel is habitat loss and degradation as a result of agricultural intensification, afforestation and urbanisation (6). Pesticide contamination is indirectly affecting the lesser kestrel due to reductions in prey, and directly affecting it during the breeding process. Hunting and egg-stealing have also contributed to sharp declines in numbers. Populations have been reduced most in the European range, particularly in Poland, the Czech Republic and Austria, where lesser kestrels are no longer breeding (2).

Casual breeder, regular passage visitor and winter visitor.

The lesser kestrel (Falco naumanni) is a small falcon. This species breeds from the Mediterranean across Afghanistan and Central Asia, to China and Mongolia. It is a summer migrant, wintering in Africa and Pakistan and sometimes even to India and Iraq. It is rare north of its breeding range, and declining in its European range. The genus name derives from Late Latin falx, falcis, a sickle, referencing the claws of the bird, and the species name commemorates the German naturalist Johann Friedrich Naumann.