Lesser Kestrel
Encyclopedia
The Lesser Kestrel is a small falcon
. This species
breeds from the Mediterranean across southern 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 Europe
an range. The scientific name of this bird commemorates the German naturalist Johann Andreas Naumann
.
It is a small bird of prey
, 27–33 cm in length with a 63–72 cm wingspan. It looks very much like the larger Common Kestrel
but has proportionally shorter wings and tail. It shares a brown back and barred grey underparts with the larger species. The male has a grey head and tail like male Common Kestrels, but lacks the dark spotting on the back, the black malar
stripe, and has grey patches in the wings.
The female and young birds are slightly paler than their relative, but are so similar that call and structure are better guides than plumage. The call is a diagnostic harsh chay-chay-chay, unlike the Common Kestrel's kee-kee-kee. Both sexes do not have dark talon
s as usual in falcons; those of this species are a peculiar whitish-horn color. This, however, is only conspicuous when seen birds at very close range, e.g. in captivity.
Despite its outward similarity, this species appears not to be closely related to the Common Kestrel. In fact, mtDNA cytochrome b
sequence
analysis (Groombridge et al. 2002) places it at a basal
position with regards to the other "true" kestrels (i.e., excluding the American Kestrel
and probably the grey African kestrels too). Its divergence is tentatively placed to around the Miocene
-Pliocene
boundary (Messinian
to Zanclean
, or about 7-3.5 mya). The morphological
similarity with the Common Kestrel is most puzzling, but still it appears to betray the present species' actual relationships: the lack of a malar
stripe seems ancestral for kestrels, and the grey wing colour unites the Lesser Kestrel with most other Falco species, but not the other true kestrels.
The Lesser Kestrel is, as the name implies, a smaller and more delicate bird than the Common Kestrel, and it is entirely sympatric in its breeding range with it; they compete to a limited extent. Thus, the possibility that there is some form of adaptive advantage to the similar coloration deserves study. Considering that the Lesser Kestrel would in fact have an advantage if some would-be predators confuse it with the larger species and consequently avoid it, it might be a case of Müllerian mimicry
.
The Lesser Kestrel eats insect
s, but also small birds, reptiles and rodents (especially mice), which are often taken on the ground. It nests colonially on buildings, cliffs, or in tree holes, laying up to 3-6 eggs. No nest structure is built, which is typical for falcons. Recent surveys (January 2007) by LPO
have revealed that in their wintering grounds, Lesser Kestrels roost communally - sometimes in huge numbers. A roost discovered in Senegal during one of these surveys held 28,600 birds, together with 16,000 Scissor-tailed Kites Chelictinia riocourii.
It is widespread and plentiful on a global scale, but in many areas of its range, it seems to be undergoing a marked and possibly accelerating decline. The IUCN has thus classed it as a vulnerable species
(VU A2bce+3bce). This means that the global population and range have declined by some 30% in the last 10 years, and is expected to continue to do so for at least another decade. Apart from possible habitat destruction
, it appears that indiscriminate use of pesticide
s has a strong effect on this species due to its insectivorous habits.
Falcon
A falcon is any species of raptor in the genus Falco. The genus contains 37 species, widely distributed throughout Europe, Asia, and North America....
. This species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
breeds from the Mediterranean across southern central Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
to China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
and Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
. It is a summer migrant
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, wintering in Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and Pakistan
Pakistan
Pakistan , officially the Islamic Republic of Pakistan is a sovereign state in South Asia. It has a coastline along the Arabian Sea and the Gulf of Oman in the south and is bordered by Afghanistan and Iran in the west, India in the east and China in the far northeast. In the north, Tajikistan...
and sometimes even to India and Iraq. It is rare north of its breeding range, and declining in its Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an range. The scientific name of this bird commemorates the German naturalist Johann Andreas Naumann
Johann Andreas Naumann
Johann Andreas Naumann was a German farmer and an amateur naturalist. He was the father of Johann Friedrich Naumann.Naumann wrote an important book on the birds of Germany, Naturgeschichte der Vögel Deutschlands ....
.
Bird of prey
Birds of prey are birds that hunt for food primarily on the wing, using their keen senses, especially vision. They are defined as birds that primarily hunt vertebrates, including other birds. Their talons and beaks tend to be relatively large, powerful and adapted for tearing and/or piercing flesh....
, 27–33 cm in length with a 63–72 cm wingspan. It looks very much like the larger Common Kestrel
Common Kestrel
The Common Kestrel is a bird of prey species belonging to the kestrel group of the falcon family Falconidae. It is also known as the European Kestrel, Eurasian Kestrel, or Old World Kestrel. In Britain, where no other brown falcon occurs, it is generally just called "the kestrel".This species...
but has proportionally shorter wings and tail. It shares a brown back and barred grey underparts with the larger species. The male has a grey head and tail like male Common Kestrels, but lacks the dark spotting on the back, the black malar
Malar
Malar may refer to:* Malar, Iran, a city in Iran* Malar, Pakistan, a town in Pakistan* Malar , a deity in the Forgotten Realms campaign setting of Dungeons & Dragons* Relating to the cheek...
stripe, and has grey patches in the wings.
The female and young birds are slightly paler than their relative, but are so similar that call and structure are better guides than plumage. The call is a diagnostic harsh chay-chay-chay, unlike the Common Kestrel's kee-kee-kee. Both sexes do not have dark talon
Claw
A claw is a curved, pointed appendage, found at the end of a toe or finger in most mammals, birds, and some reptiles. However, the word "claw" is also often used in reference to an invertebrate. Somewhat similar fine hooked structures are found in arthropods such as beetles and spiders, at the end...
s as usual in falcons; those of this species are a peculiar whitish-horn color. This, however, is only conspicuous when seen birds at very close range, e.g. in captivity.
Despite its outward similarity, this species appears not to be closely related to the Common Kestrel. In fact, mtDNA cytochrome b
Cytochrome b
Cytochrome b/b6 is the main subunit of transmembrane cytochrome bc1 and b6f complexes. In addition, it commonly refers to a region of mtDNA used for population genetics and phylogenetics.- Function :...
sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
analysis (Groombridge et al. 2002) places it at a basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
position with regards to the other "true" kestrels (i.e., excluding the American Kestrel
American Kestrel
The American Kestrel , sometimes colloquially known as the Sparrow Hawk, is a small falcon, and the only kestrel found in the Americas. It is the most common falcon in North America, and is found in a wide variety of habitats. At long, it is also the smallest falcon in North America...
and probably the grey African kestrels too). Its divergence is tentatively placed to around the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
-Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
boundary (Messinian
Messinian
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.332 ± 0.005 Ma...
to Zanclean
Zanclean
The Zanclean is the lowest stage or earliest age on the geologic time scale of the Pliocene. It spans the time between 5.332 and 3.6 Ma ± 0.005 Ma . It is preceded by the Messinian age of the Miocene epoch, and followed by the Piacenzian age....
, or about 7-3.5 mya). The morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
similarity with the Common Kestrel is most puzzling, but still it appears to betray the present species' actual relationships: the lack of a malar
Malar
Malar may refer to:* Malar, Iran, a city in Iran* Malar, Pakistan, a town in Pakistan* Malar , a deity in the Forgotten Realms campaign setting of Dungeons & Dragons* Relating to the cheek...
stripe seems ancestral for kestrels, and the grey wing colour unites the Lesser Kestrel with most other Falco species, but not the other true kestrels.
The Lesser Kestrel is, as the name implies, a smaller and more delicate bird than the Common Kestrel, and it is entirely sympatric in its breeding range with it; they compete to a limited extent. Thus, the possibility that there is some form of adaptive advantage to the similar coloration deserves study. Considering that the Lesser Kestrel would in fact have an advantage if some would-be predators confuse it with the larger species and consequently avoid it, it might be a case of Müllerian mimicry
Müllerian mimicry
Müllerian mimicry is a natural phenomenon when two or more harmful species, that may or may not be closely related and share one or more common predators, have come to mimic each other's warning signals...
.
The Lesser Kestrel eats insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, but also small birds, reptiles and rodents (especially mice), which are often taken on the ground. It nests colonially on buildings, cliffs, or in tree holes, laying up to 3-6 eggs. No nest structure is built, which is typical for falcons. Recent surveys (January 2007) by LPO
LPO
LPO may refer to:*LPO-50, a flamethrower built by the Soviet Union*Landing Page Optimization*Leading Petty Officer*Legal Process Outsourcing*Libertarian Party of Ohio*Libertarian Party of Ontario*Libertarian Party of Oregon...
have revealed that in their wintering grounds, Lesser Kestrels roost communally - sometimes in huge numbers. A roost discovered in Senegal during one of these surveys held 28,600 birds, together with 16,000 Scissor-tailed Kites Chelictinia riocourii.
It is widespread and plentiful on a global scale, but in many areas of its range, it seems to be undergoing a marked and possibly accelerating decline. The IUCN has thus classed it as a vulnerable species
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
(VU A2bce+3bce). This means that the global population and range have declined by some 30% in the last 10 years, and is expected to continue to do so for at least another decade. Apart from possible habitat destruction
Habitat destruction
Habitat destruction is the process in which natural habitat is rendered functionally unable to support the species present. In this process, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Habitat destruction by human activity mainly for the purpose of...
, it appears that indiscriminate use of pesticide
Pesticide
Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.A pesticide may be a chemical unicycle, biological agent , antimicrobial, disinfectant or device used against any pest...
s has a strong effect on this species due to its insectivorous habits.