Greater Kestrel
Encyclopedia
The Greater Kestrel or White-eyed Kestrel (Falco rupicoloides) is a bird of prey
belonging to the falcon
family Falconidae
. It is one of the largest kestrel
s and is found in open country in southern and eastern Africa
.
of the adult is mainly pale rufous, both above and below. The back, upperwing and flanks are barred with black. The breast has dark streaks and the head is streaked but has no malar stripe unlike the Common
and Lesser Kestrel
s. The rump and tail are grey with black bars; the tail has a white tip. In flight, the whitish underwing contrasts with the darker body. The iris
of the eye is whitish, distinguishing the bird from any similar species. The bill is mainly blue-grey and the feet and cere
are yellow. Juvenile
birds have rufous instead of grey on the tail, streaked flanks and a dark eye.
The bird is 29–37 cm long with a wingspan of 68–84 cm. The southern subspecies
F. r. rupicoloides weighs about 181–334 grams. The form F. r. arthuri is smaller, weighing about 165–252 grams. The northern subspecies F. r. fieldi is also small and is paler than the others.
The species is usually silent but has a shrill, repeated call.
, savanna
s and semi-desert. It is often associated with acacia
s. It prefers areas where the ground cover is lower than 50 cm. It is found from sea-level up to 2150 metres, particularly between 800 and 1800 metres.
It is fairly common and widespread in the southern parts of its range but is scarce and patchily distributed further north. The form F. r. rupicoloides breeds in Namibia
, Botswana
, Zimbabwe
, parts of Angola
and Zambia
and in much of South Africa
apart from the wetter regions of the south and east. F. r. arthuri is found in Kenya
and northern Tanzania
while F. r. fieldi occurs in Ethiopia
, Eritrea
, northern Somalia
and probably northern Kenya
.
The total range covers about 3.5 million km2. The population is stable and is likely to be in the order of 100,000 to 200,000 pairs. Most birds are sedentary but some are nomadic or dispersive.
s such as grasshopper
s, termite
s, beetle
s and solifugids. It also takes lizard
s and sometimes small birds, mammal
s and snake
s. It mainly catches prey on the ground. It is attracted to fires where it catches insects and other prey as they flee from the flames. Excess food may be cached underneath vegetation or stones.
The breeding season varies between different regions. In the south it lasts from July to April with a peak between September and December. Breeding takes place in all months in Kenya and Tanzania but is concentrated between April and July. The season lasts from April to August in Somalia.
Greater Kestrels use the old nest
of another bird for breeding, such as that of a Cape Crow
or Pied Crow
. A typical site is between 2 and 20 metres above the ground in a tree or sometimes on a telegraph pole or pylon
. Two to seven eggs
are laid with three or four being most common. They are incubated
for 22 to 23 days, mainly by the female. The young birds fledge
after 30 to 34 days and remain dependent on their parents for at least 26 days longer.
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....
belonging to the falcon
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....
family Falconidae
Falconidae
The falcons and caracaras are around 60 species of diurnal birds of prey that make up the family Falconidae. The family is divided into two subfamiles, Polyborinae, which includes the caracaras and forest falcons, and Falconinae, the falcons, kestrels and falconets.-Description:Falcons and...
. It is one of the largest kestrel
Kestrel
The name kestrel, is given to several different members of the falcon genus, Falco. Kestrels are most easily distinguished by their typical hunting behaviour which is to hover at a height of around over open country and swoop down on prey, usually small mammals, lizards or large insects...
s and is found in open country in southern and eastern 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...
.
Description
The plumagePlumage
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
of the adult is mainly pale rufous, both above and below. The back, upperwing and flanks are barred with black. The breast has dark streaks and the head is streaked but has no malar stripe unlike the Common
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...
and Lesser Kestrel
Lesser Kestrel
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 European...
s. The rump and tail are grey with black bars; the tail has a white tip. In flight, the whitish underwing contrasts with the darker body. The iris
Iris (anatomy)
The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...
of the eye is whitish, distinguishing the bird from any similar species. The bill is mainly blue-grey and the feet and cere
Cère
The Cère is a long river in south-western France, left tributary of the Dordogne River. Its source is in the south-western Massif Central, near the mountain Plomb du Cantal...
are yellow. Juvenile
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different from the adult form, particularly in terms of their colour...
birds have rufous instead of grey on the tail, streaked flanks and a dark eye.
The bird is 29–37 cm long with a wingspan of 68–84 cm. The southern subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
F. r. rupicoloides weighs about 181–334 grams. The form F. r. arthuri is smaller, weighing about 165–252 grams. The northern subspecies F. r. fieldi is also small and is paler than the others.
The species is usually silent but has a shrill, repeated call.
Habitat and range
It occurs in open, arid areas where it inhabits grasslandGrassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
, savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
s and semi-desert. It is often associated with acacia
Acacia
Acacia is a genus of shrubs and trees belonging to the subfamily Mimosoideae of the family Fabaceae, first described in Africa by the Swedish botanist Carl Linnaeus in 1773. Many non-Australian species tend to be thorny, whereas the majority of Australian acacias are not...
s. It prefers areas where the ground cover is lower than 50 cm. It is found from sea-level up to 2150 metres, particularly between 800 and 1800 metres.
It is fairly common and widespread in the southern parts of its range but is scarce and patchily distributed further north. The form F. r. rupicoloides breeds in Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...
, Botswana
Botswana
Botswana, officially the Republic of Botswana , is a landlocked country located in Southern Africa. The citizens are referred to as "Batswana" . Formerly the British protectorate of Bechuanaland, Botswana adopted its new name after becoming independent within the Commonwealth on 30 September 1966...
, Zimbabwe
Zimbabwe
Zimbabwe is a landlocked country located in the southern part of the African continent, between the Zambezi and Limpopo rivers. It is bordered by South Africa to the south, Botswana to the southwest, Zambia and a tip of Namibia to the northwest and Mozambique to the east. Zimbabwe has three...
, parts of Angola
Angola
Angola, officially the Republic of Angola , is a country in south-central Africa bordered by Namibia on the south, the Democratic Republic of the Congo on the north, and Zambia on the east; its west coast is on the Atlantic Ocean with Luanda as its capital city...
and Zambia
Zambia
Zambia , officially the Republic of Zambia, is a landlocked country in Southern Africa. The neighbouring countries are the Democratic Republic of the Congo to the north, Tanzania to the north-east, Malawi to the east, Mozambique, Zimbabwe, Botswana and Namibia to the south, and Angola to the west....
and in much of South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
apart from the wetter regions of the south and east. F. r. arthuri is found in Kenya
Kenya
Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...
and northern Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...
while F. r. fieldi occurs in Ethiopia
Ethiopia
Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...
, Eritrea
Eritrea
Eritrea , officially the State of Eritrea, is a country in the Horn of Africa. Eritrea derives it's name from the Greek word Erethria, meaning 'red land'. The capital is Asmara. It is bordered by Sudan in the west, Ethiopia in the south, and Djibouti in the southeast...
, northern Somalia
Somalia
Somalia , officially the Somali Republic and formerly known as the Somali Democratic Republic under Socialist rule, is a country located in the Horn of Africa. Since the outbreak of the Somali Civil War in 1991 there has been no central government control over most of the country's territory...
and probably northern Kenya
Kenya
Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...
.
The total range covers about 3.5 million km2. The population is stable and is likely to be in the order of 100,000 to 200,000 pairs. Most birds are sedentary but some are nomadic or dispersive.
Feeding
The Greater Kestrel usually hunts from an exposed perch such as a tree or rock. It also hovers like several other kestrels. It feeds mainly on invertebrateInvertebrate
An invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s such as grasshopper
Grasshopper
The grasshopper is an insect of the suborder Caelifera in the order Orthoptera. To distinguish it from bush crickets or katydids, it is sometimes referred to as the short-horned grasshopper...
s, termite
Termite
Termites are a group of eusocial insects that, until recently, were classified at the taxonomic rank of order Isoptera , but are now accepted as the epifamily Termitoidae, of the cockroach order Blattodea...
s, beetle
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
s and solifugids. It also takes lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
s and sometimes small birds, mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s and snake
Snake
Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...
s. It mainly catches prey on the ground. It is attracted to fires where it catches insects and other prey as they flee from the flames. Excess food may be cached underneath vegetation or stones.
Reproduction
Greater Kestrels use the old nest
Nest
A nest is a place of refuge to hold an animal's eggs or provide a place to live or raise offspring. They are usually made of some organic material such as twigs, grass, and leaves; or may simply be a depression in the ground, or a hole in a tree, rock or building...
of another bird for breeding, such as that of a Cape Crow
Cape Crow
The Cape Crow or Black Crow is slightly larger than the Carrion Crow and is completely black with a slight gloss of purple in the feathers. It has proportionately longer legs, wings and tail too and has a much longer, slimmer bill that seems to be designed for probing into the ground for...
or Pied Crow
Pied Crow
The Pied Crow is a widely distributed African bird species in the crow genus.Structurally, the Pied Crow is better thought of as a small crow-sized Raven, especially as it can hybridise with the Somali Crow where their ranges meet in the Horn of Africa...
. A typical site is between 2 and 20 metres above the ground in a tree or sometimes on a telegraph pole or pylon
Electricity pylon
A transmission tower is a tall structure, usually a steel lattice tower, used to support an overhead power line. They are used in high-voltage AC and DC systems, and come in a wide variety of shapes and sizes...
. Two to seven eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
are laid with three or four being most common. They are incubated
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
for 22 to 23 days, mainly by the female. The young birds fledge
Fledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
after 30 to 34 days and remain dependent on their parents for at least 26 days longer.