African Crake
Encyclopedia
The African Crake is a bird in the rail family
that breeds in most of sub-Saharan
Africa away from the arid south and southwest. It is seasonally common in most of its range other than the rainforest
s and areas that have low annual rainfall. This crake is a partial migrant
, moving away from the equator as soon as the rains provide sufficient grass cover to allow it to breed elsewhere. There have been a few records of vagrant
birds reaching Atlantic islands. This species nests in a wide variety of grassland types, and agricultural land with tall crops may also be used.
A smallish crake, the African Crake has brown-streaked blackish upperparts, bluish-grey underparts and black-and-white barring on the flanks and belly. It has a stubby red bill, red eyes, and a white line from the bill to above the eye. It is smaller than its closest relative, the Corn Crake
; that species is also lighter-plumaged
, and has an eye stripe. The African Crake has a range of calls, the most characteristic being a series of rapid grating krrr notes. It is active during the day, and is territorial
on both the breeding and non-breeding grounds; the male has a threat display
, and may fight at territory boundaries. The nest is a shallow cup of grass leaves built in a depression under a grass tussock or small bush. The 3–11 eggs start hatching after about 14 days, and the black, downy precocial
chicks fledge
after four to five weeks. The African Crake feeds on a wide range of invertebrate
s, along with some small frogs and fish, and plant material, especially grass seeds. It may itself be eaten by large birds of prey
; snakes; or mammals, including humans, and can host parasites
. Although it may be displaced temporarily by the burning of grassland, or permanently by agriculture, wetland drainage or urbanisation, its large range and population mean that it is not considered to be threatened.
are a bird family
comprising nearly 150 species. Although the origins of the group are lost in antiquity, the largest number of species and the most primitive forms are found in the Old World
, suggesting that this family originated there. The taxonomy of the small crakes is complicated, but the closest relative of the African Crake is the Corn Crake, C. crex, which breeds in Europe and Asia, but winters in Africa. The African Crake was first described as Ortygometra egregia by Wilhelm Peters
in 1854 from a specimen collected in Mozambique, but the genus name failed to become established. For some time it was placed as the sole member of the genus Crecopsis but subsequently moved to Crex
, created for this species by German naturalist and ornithologist Johann Matthäus Bechstein
in 1803. Richard Bowdler Sharpe
considered that the African bird differed sufficiently from the Corn Crake to have its own genus Crecopsis, and later authors sometimes placed it in Porzana
, based on a resemblance to the Ash-throated Crake
, P. albicollis. Structural differences rule out Porzana, and the placement in Crex is now the most common and best-supported treatment. Phylogeny
and morphology
confirm that the Porzana crakes are the closest relatives of the Crex genus. The genus name is onomatopoeic, referring to the repetitive grating call of the Corn Crake, and the species name egregia derives from Latin
egregius, "outstanding, prominent".
s are dark brown, and the flanks and sides of the belly are barred black and white. The eye is red, the bill is reddish, and the legs and feet are light brown or grey. The sexes are similar in appearance, although the female is slightly smaller and duller than the male, with a less contrasting head pattern. Immature birds have darker and duller upperparts than the adult, a dark bill, grey eye, and less barring on the underparts. There are no subspecific
or other geographical variations in plumage. This crake has a complete moult after breeding, mainly prior to migration. Although this species occurs in fairly open habitats, it lacks the pure white undertail used for signalling in open water or gregarious species like the coot
s and moorhen
s.
The African Crake is larger than the Corn Crake, which also has darker upperparts, a plain grey face and different underparts barring pattern. In flight, the African species has shorter, blunter wings with a less prominent white leading edge, and deeper wingbeats than its relative. Other sympatric
crakes are smaller with white markings on the upperparts, different underparts patterns and a shorter bill. The African Rail
has dark brown upperparts, a long red bill and red legs and feet.
The rasping advertising call is readily distinguished from the hwitt-hwitt-hwitt of Spotted Crake
, the monotonous clockwork tak-tak-tak-tak-tak of Striped Crake
, or the quick-quick of Baillon's Crake
. The Corn Crake is silent in Africa.
, South Africa, except in arid areas of south and southwest Africa where the annual summer rainfall is less than 300 mm (11.8 in). It is widespread and locally common in most of its range, apart from the rainforest
s and the drier regions. Nearly all the South Africa population of about 8,000 birds occur in KwaZulu-Natal and the former Transvaal Province
, and much good habitat is protected in the Kruger National Park
and iSimangaliso Wetland Park. This crake is only a vagrant
to southern Mauritania, southwest Niger, Lesotho, South Africa's northern and eastern Cape Province
and North West Province
, and southern Botswana. Further afield, it is rare on Bioko Island
(Equatorial Guinea), and there have been two records each for Sao Tome
and Tenerife
, the Canary Islands
birds being the first records for the Western Palaeartic. Holocene
remains from North Africa
suggest that the species may have been more widespread when the climate was wetter in what is now the Sahara
.
This crake is a partial migrant
, but although it is less skulking than many of its relatives, its movements are complex and poorly studied; the distribution map is therefore largely hypothetical. It is mainly a wet-season breeder, and many birds move away from the equator as soon as the rains provide sufficient grass cover to allow them to breed elsewhere. Southward movement is mainly from November to April, the return north beginning when burning or drought reduces the grass cover again. This species is present throughout the year in some West African countries, and in equatorial regions, but even in those areas numbers vary seasonally due to local movements; north-south migration has been noted within countries including Nigeria, Senegal, The Gambia, Ivory Coast and Cameroon. Migration takes place at night and involves small groups of up to eight birds; It may be one or two months after the rains begin before the grass is sufficiently high for breeding birds to arrive. Even in southern Africa, some birds may stay after breeding if enough usable habitat remains.
The habitat is predominantly grassland, ranging from wetland edges and seasonal floodlands to savanna
, lightly wooded dry grassland, and grassy forest clearings. The crake also frequents maize, rice and cotton crops, derelict farmland and sugarcane plantations close to water. A wide range of grass species are used, with a preferred height of 0.3–1 m (1– 3 ft) tall but vegetation is acceptable up to 2 m (6 ft) tall. It normally prefers moister and shorter grassland habitats than does the Corn Crake, and its breeding territories often contain or are close to thickets or termite
mounds. It occurs from sea level to 2,000 m (6,500 ft) but is rare in the higher altitude grasslands. Its grassland habitat is frequently burned in the dry season, forcing the birds to move elsewhere. In an East African study, the average area occupied by one bird was 2.6 ha (6.4 acres) when breeding, and 1.97 to 2.73 ha (4.9–6.75 acres) at other times. The highest densities occur in lush or moist grassland such as the Okavango Delta
.
The African Crake is territorial on both the breeding and non-breeding grounds; the male threat display involves the bird standing upright and spreading the feathers of the flanks and belly like a fan to show the barred underparts. He may march towards the intruder, or walk side by side with another displaying male. The female may accompany the male, but with feathers less widely fanned. Fighting at territorial boundaries involves the male birds jumping at each other and pecking. Paired females will attack other females in the territory, especially if the male has shown an interest in them.
size is from 3 to 11 pink-coloured eggs; the first is often laid when the nest is little more than a pad of grass, and a further egg is laid on each subsequent day. Both sexes incubate, and the eggs start hatching after about 14 days; all hatch with 48 hours despite the extended laying period. The black, downy precocial
chicks soon leave the nest but are fed and protected by the parents. Fledging
occurs after four to five weeks, and the young can fly before they are fully grown. It is not known whether a second brood is raised.
s including earthworm
s, gastropods, molluscs and the adults and larva
e of insects, especially termite
s, ant
s, beetle
s and grasshopper
s. Vertebrate
prey such as small frogs or fish may also be taken. Plant material is eaten, especially grass seeds, but also green shoots, leaves and other seeds. The crake searches for food both within vegetation and in the open, picking insects and seeds from the ground, turning over leaf litter, or digging with its bill in soft or very dry ground. It will chase faster moving prey, reach up to take food from plants, and wade to pluck food items from the water. Crop plants such as rice, maize and peas may sometimes be eaten, but this bird is not an agricultural pest species. It forages singly, in pairs or in family groups, sometimes in association with other grassland birds such as Great Snipe
s, Blue Quail
s and Corn Crakes. Chicks are fed mainly on animal food. As with other rails, grit is swallowed to help break up food in the stomach.
, Serval
, cat
s, the Black-headed Heron
, Dark Chanting Goshawk
, African Hawk-Eagle and Wahlberg's Eagle
. In South Africa, newly hatched chicks were taken by a Boomslang
. If surprised, an African Crake will leap vertically into the air before running away, a tactic believed to help it to evade snakes or terrestrial mammals.
Parasites of this species include tick
s of the family Ixodidae
, and a feather mite
, Metanalges elongatus, of the subspecies M. e. curtus. The nominate form of the mite occurs thousands of kilometres away in New Caledonia
.
on the IUCN Red List
. Overgrazing, agriculture and the loss of wetland and moist grassland have reduced the availability of suitable habitat in many areas, such as some parts of the southern KwaZulu-Natal coast which have been urbanised or planted with sugarcane. In other areas, grassland may have increased locally in recent years as woodland is cleared. This crake is considered to be good eating, and is killed for food in some regions. Despite these adverse factors, it appears to be under no real threat.
Although most rails in the Old World are covered by the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA), the African Crake is not listed even in Kenya, where it is considered "near-threatened". Like its relative, the Corn Crake, it is too terrestrial to be classed as a wetland species.
Rallidae
The rails, or Rallidae, are a large cosmopolitan family of small to medium-sized birds. The family exhibits considerable diversity and the family also includes the crakes, coots, and gallinules...
that breeds in most of sub-Saharan
Sahara
The Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...
Africa away from the arid south and southwest. It is seasonally common in most of its range other than the rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
s and areas that have low annual rainfall. This crake is a partial 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...
, moving away from the equator as soon as the rains provide sufficient grass cover to allow it to breed elsewhere. There have been a few records of vagrant
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...
birds reaching Atlantic islands. This species nests in a wide variety of grassland types, and agricultural land with tall crops may also be used.
A smallish crake, the African Crake has brown-streaked blackish upperparts, bluish-grey underparts and black-and-white barring on the flanks and belly. It has a stubby red bill, red eyes, and a white line from the bill to above the eye. It is smaller than its closest relative, the Corn Crake
Corn Crake
The Corn Crake, Corncrake or Landrail is a bird in the rail family. It breeds in Europe and Asia as far east as western China, and migrates to Africa for the winter...
; that species is also lighter-plumaged
Plumage
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...
, and has an eye stripe. The African Crake has a range of calls, the most characteristic being a series of rapid grating krrr notes. It is active during the day, and is territorial
Territory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
on both the breeding and non-breeding grounds; the male has a threat display
Threat display
Threat display is a type of display behaviour aiming at intimidation of a potential enemy. It may be directed at a rival of the same species , or at a potential threat from a different species....
, and may fight at territory boundaries. The nest is a shallow cup of grass leaves built in a depression under a grass tussock or small bush. The 3–11 eggs start hatching after about 14 days, and the black, downy precocial
Precocial
In biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial," where the young are born or hatched helpless. Extremely precocial species may be called...
chicks 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 four to five weeks. The African Crake feeds on a wide range of invertebrate
Invertebrate
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, along with some small frogs and fish, and plant material, especially grass seeds. It may itself be eaten by large birds of prey
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....
; snakes; or mammals, including humans, and can host parasites
Parasitism
Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...
. Although it may be displaced temporarily by the burning of grassland, or permanently by agriculture, wetland drainage or urbanisation, its large range and population mean that it is not considered to be threatened.
Taxonomy
The railsRallidae
The rails, or Rallidae, are a large cosmopolitan family of small to medium-sized birds. The family exhibits considerable diversity and the family also includes the crakes, coots, and gallinules...
are a bird family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
comprising nearly 150 species. Although the origins of the group are lost in antiquity, the largest number of species and the most primitive forms are found in the Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
, suggesting that this family originated there. The taxonomy of the small crakes is complicated, but the closest relative of the African Crake is the Corn Crake, C. crex, which breeds in Europe and Asia, but winters in Africa. The African Crake was first described as Ortygometra egregia by Wilhelm Peters
Wilhelm Peters
Wilhelm Karl Hartwich Peters was a German naturalist and explorer.He was assistant to Johannes Peter Müller and later curator of the Berlin Zoological Museum. In September 1842 he travelled to Mozambique via Angola. He returned to Berlin with an enormous collection of natural history specimens...
in 1854 from a specimen collected in Mozambique, but the genus name failed to become established. For some time it was placed as the sole member of the genus Crecopsis but subsequently moved to Crex
Crex
Crex is a small genus of birds in the rail family. It contains two species, the Corn Crake, C. crex, which breeds across Europe and Asia and winters in southern Africa, and the African Crake, C. egregia, which migrates within Africa. Both are short-billed rails with blackish-brown upperparts,...
, created for this species by German naturalist and ornithologist Johann Matthäus Bechstein
Johann Matthäus Bechstein
Johann Matthäus Bechstein was a German naturalist, forester, ornithologist and entomologist. In Great Britain, he was known for his treatise on singing birds .-Biography:Bechstein was born in Waltershausen in the district of Gotha in Thuringia...
in 1803. Richard Bowdler Sharpe
Richard Bowdler Sharpe
Richard Bowdler Sharpe was an English zoologist.-Biography:Sharpe was born in London and studied at Brighton College, The King's School, Peterborough and Loughborough Grammar School. At the age of sixteen he went to work for Smith & Sons in London...
considered that the African bird differed sufficiently from the Corn Crake to have its own genus Crecopsis, and later authors sometimes placed it in Porzana
Porzana
Porzana is a genus of birds in the crake or rail family, Rallidae. It has a global distribution, contains 13 living species, and 4-5 recently extinct ones...
, based on a resemblance to the Ash-throated Crake
Ash-throated Crake
The Ash-throated Crake is a species of bird in the Rallidae family.It is found in Argentina, Bolivia, Brazil, Colombia, French Guiana, Guyana, Paraguay, Peru, Suriname, Trinidad and Tobago, and Venezuela....
, P. albicollis. Structural differences rule out Porzana, and the placement in Crex is now the most common and best-supported treatment. Phylogeny
Phylogenetics
In biology, phylogenetics is the study of evolutionary relatedness among groups of organisms , which is discovered through molecular sequencing data and morphological data matrices...
and morphology
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....
confirm that the Porzana crakes are the closest relatives of the Crex genus. The genus name is onomatopoeic, referring to the repetitive grating call of the Corn Crake, and the species name egregia derives from Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
egregius, "outstanding, prominent".
Description
The African Crake is a smallish crake, 20–23 cm (7.8–9.1 in) long with a 40–42 cm (15.7–16.5 in) wingspan. The male has blackish upperparts streaked with olive-brown, apart from the nape and hindneck which are plain pale brown; there is a white streak from the base of the bill to above the eye. The sides of the head, foreneck, throat and breast are bluish-grey, the flight featherFlight feather
Flight feathers are the long, stiff, asymmetrically shaped, but symmetrically paired feathers on the wings or tail of a bird; those on the wings are called remiges while those on the tail are called rectrices . Their primary function is to aid in the generation of both thrust and lift, thereby...
s are dark brown, and the flanks and sides of the belly are barred black and white. The eye is red, the bill is reddish, and the legs and feet are light brown or grey. The sexes are similar in appearance, although the female is slightly smaller and duller than the male, with a less contrasting head pattern. Immature birds have darker and duller upperparts than the adult, a dark bill, grey eye, and less barring on the underparts. There are no subspecific
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...
or other geographical variations in plumage. This crake has a complete moult after breeding, mainly prior to migration. Although this species occurs in fairly open habitats, it lacks the pure white undertail used for signalling in open water or gregarious species like the coot
Coot
Coots are medium-sized water birds that are members of the rail family Rallidae. They constitute the genus Fulica. Coots have predominantly black plumage, and, unlike many of the rails, they are usually easy to see, often swimming in open water...
s and moorhen
Moorhen
Moorhens, sometimes called marsh hens, are medium-sized water birds that are members of the rail family Rallidae. They constitute the genus Gallinula....
s.
The African Crake is larger than the Corn Crake, which also has darker upperparts, a plain grey face and different underparts barring pattern. In flight, the African species has shorter, blunter wings with a less prominent white leading edge, and deeper wingbeats than its relative. Other sympatric
Sympatry
In biology, two species or populations are considered sympatric when they exist in the same geographic area and thus regularly encounter one another. An initially-interbreeding population that splits into two or more distinct species sharing a common range exemplifies sympatric speciation...
crakes are smaller with white markings on the upperparts, different underparts patterns and a shorter bill. The African Rail
African Rail
The African Rail is a small wetland bird of the rail family.Its breeding habitat is marshes and reedbeds across eastern and southern Africa from Ethiopia to South Africa...
has dark brown upperparts, a long red bill and red legs and feet.
Voice
Like other rails, this species has a wide range of vocalisations. The male's territorial and advertising call is a series of rapid grating krrr notes repeated two or three times a second for several minutes. It is given most often in the breeding season, usually early or late in the day, but sometimes continues after dark or starts before dawn. The male stands upright with his neck extended when advertising, but will also call when chasing intruders on the ground or in flight. Both sexes give a sharp, loud kip call as an alarm or during territorial interactions, adapting a similar pose as for the advertising call. Once breeding starts, the birds become much quieter, but territorial birds commence the kip call again during the non-breeding season, especially when there is a high density of African Crakes in the area. A wheezy kraaa is associated with threat displays and copulation; imitation of this call by a human can bring a rail to within 10 m (30 ft). Newly hatched chicks make a soft wheeeez call, and older chicks cheep.The rasping advertising call is readily distinguished from the hwitt-hwitt-hwitt of Spotted Crake
Spotted Crake
The Spotted Crake is a small waterbird, of the family Rallidae.Their breeding habitat is marshes and sedge beds across temperate Europe into western Asia. They nest in a dry location in marsh vegetation, laying 6-15 eggs...
, the monotonous clockwork tak-tak-tak-tak-tak of Striped Crake
Striped Crake
The Striped Crake is a species of bird in the Rallidae family. It is the only species in the genus Aenigmatolimnas....
, or the quick-quick of Baillon's Crake
Baillon's Crake
The Baillon's Crake is a very small waterbird of the family Rallidae.-Distribution:Their breeding habitat is sedge beds in Europe, mainly in the east, and across Asia. They used to breed in Great Britain up to the mid-19th century, but the western European population declined through drainage....
. The Corn Crake is silent in Africa.
Distribution and habitat
The African Crake occurs throughout sub-Saharan Africa from Senegal east to Kenya and south to KwaZulu-NatalKwaZulu-Natal
KwaZulu-Natal is a province of South Africa. Prior to 1994, the territory now known as KwaZulu-Natal was made up of the province of Natal and the homeland of KwaZulu....
, South Africa, except in arid areas of south and southwest Africa where the annual summer rainfall is less than 300 mm (11.8 in). It is widespread and locally common in most of its range, apart from the rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
s and the drier regions. Nearly all the South Africa population of about 8,000 birds occur in KwaZulu-Natal and the former Transvaal Province
Transvaal Province
Transvaal Province was a province of the Union of South Africa from 1910 to 1961, and of its successor, the Republic of South Africa, from 1961 until the end of apartheid in 1994 when a new constitution subdivided it.-History:...
, and much good habitat is protected in the Kruger National Park
Kruger National Park
Kruger National Park is one of the largest game reserves in Africa. It covers and extends from north to south and from east to west.To the west and south of the Kruger National Park are the two South African provinces of Limpopo and Mpumalanga. In the north is Zimbabwe, and to the east is...
and iSimangaliso Wetland Park. This crake is only a vagrant
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...
to southern Mauritania, southwest Niger, Lesotho, South Africa's northern and eastern Cape Province
Cape Province
The Province of the Cape of Good Hope was a province in the Union of South Africa and subsequently the Republic of South Africa...
and North West Province
North West (South African province)
North West is a province of South Africa. Its capital is Mafikeng. The province is located to the west of the major population centre of Gauteng.-History:...
, and southern Botswana. Further afield, it is rare on Bioko Island
Bioko
Bioko is an island 32 km off the west coast of Africa, specifically Cameroon, in the Gulf of Guinea. It is the northernmost part of Equatorial Guinea with a population of 124,000 and an area of . It is volcanic with its highest peak the Pico Basile at .-Geography:Bioko has a total area of...
(Equatorial Guinea), and there have been two records each for Sao Tome
São Tomé and Príncipe
São Tomé and Príncipe, officially the Democratic Republic of São Tomé and Príncipe, is a Portuguese-speaking island nation in the Gulf of Guinea, off the western equatorial coast of Central Africa. It consists of two islands: São Tomé and Príncipe, located about apart and about , respectively, off...
and Tenerife
Tenerife
Tenerife is the largest and most populous island of the seven Canary Islands, it is also the most populated island of Spain, with a land area of 2,034.38 km² and 906,854 inhabitants, 43% of the total population of the Canary Islands. About five million tourists visit Tenerife each year, the...
, the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
birds being the first records for the Western Palaeartic. Holocene
Holocene
The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...
remains from North Africa
North Africa
North Africa or Northern Africa is the northernmost region of the African continent, linked by the Sahara to Sub-Saharan Africa. Geopolitically, the United Nations definition of Northern Africa includes eight countries or territories; Algeria, Egypt, Libya, Morocco, South Sudan, Sudan, Tunisia, and...
suggest that the species may have been more widespread when the climate was wetter in what is now the Sahara
Sahara
The Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...
.
This crake is a partial 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...
, but although it is less skulking than many of its relatives, its movements are complex and poorly studied; the distribution map is therefore largely hypothetical. It is mainly a wet-season breeder, and many birds move away from the equator as soon as the rains provide sufficient grass cover to allow them to breed elsewhere. Southward movement is mainly from November to April, the return north beginning when burning or drought reduces the grass cover again. This species is present throughout the year in some West African countries, and in equatorial regions, but even in those areas numbers vary seasonally due to local movements; north-south migration has been noted within countries including Nigeria, Senegal, The Gambia, Ivory Coast and Cameroon. Migration takes place at night and involves small groups of up to eight birds; It may be one or two months after the rains begin before the grass is sufficiently high for breeding birds to arrive. Even in southern Africa, some birds may stay after breeding if enough usable habitat remains.
The habitat is predominantly grassland, ranging from wetland edges and seasonal floodlands to 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...
, lightly wooded dry grassland, and grassy forest clearings. The crake also frequents maize, rice and cotton crops, derelict farmland and sugarcane plantations close to water. A wide range of grass species are used, with a preferred height of 0.3–1 m (1– 3 ft) tall but vegetation is acceptable up to 2 m (6 ft) tall. It normally prefers moister and shorter grassland habitats than does the Corn Crake, and its breeding territories often contain or are close to thickets or 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...
mounds. It occurs from sea level to 2,000 m (6,500 ft) but is rare in the higher altitude grasslands. Its grassland habitat is frequently burned in the dry season, forcing the birds to move elsewhere. In an East African study, the average area occupied by one bird was 2.6 ha (6.4 acres) when breeding, and 1.97 to 2.73 ha (4.9–6.75 acres) at other times. The highest densities occur in lush or moist grassland such as the Okavango Delta
Okavango Delta
The Okavango Delta , in Botswana, is the world's largest inland delta. It is formed where the Okavango River empties onto a swamp in an endorheic basin in the Kalahari Desert, where most of the water is lost to evaporation and transpiration instead of draining into the sea...
.
Behaviour
The African Crake is active during the day, especially at dusk, during light rain, or after heavier rain. It is less skulking and easier to flush from cover than other crakes, and is often seen at the edges of roads and tracks. An observer in a vehicle can approach to within 1 m (3 ft). When a bird is flushed it normally flies less than 50 m (150 ft), but new arrivals may occasionally fly twice as far. A flushed crake will frequently land in a wet area or behind a thicket, and crouch on landing. In short grass, it can escape from a dog using its speed and maneuverability, running with the body held almost horizontal. This crake may roost in a depression near grass tussock and it will bathe in puddles.The African Crake is territorial on both the breeding and non-breeding grounds; the male threat display involves the bird standing upright and spreading the feathers of the flanks and belly like a fan to show the barred underparts. He may march towards the intruder, or walk side by side with another displaying male. The female may accompany the male, but with feathers less widely fanned. Fighting at territorial boundaries involves the male birds jumping at each other and pecking. Paired females will attack other females in the territory, especially if the male has shown an interest in them.
Breeding
Breeding behavior commences with a courtship chase with the female running in a crouch, pursued by the male, who adopts a more upright stance and has his neck outstretched. The female may stop and lower her head and tail to allow copulation; this takes just a few seconds, but may be repeated several times in an hour. The nest is a shallow cup of grass leaves, sometimes with a loose canopy, built in a depression and hidden under a grass tussock or small bush; it may be on dry ground or slightly raised above standing water, or occasionally floating. The nest is about 20 cm (8 in) across with the internal cup 2–5 cm (1–2 in) deep, and 11–12 cm (5–6 in) wide. The clutchClutch (eggs)
A clutch of eggs refers to all the eggs produced by birds or reptiles, often at a single time, particularly those laid in a nest.In birds, destruction of a clutch by predators, , results in double-clutching...
size is from 3 to 11 pink-coloured eggs; the first is often laid when the nest is little more than a pad of grass, and a further egg is laid on each subsequent day. Both sexes incubate, and the eggs start hatching after about 14 days; all hatch with 48 hours despite the extended laying period. The black, downy precocial
Precocial
In biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial," where the young are born or hatched helpless. Extremely precocial species may be called...
chicks soon leave the nest but are fed and protected by the parents. Fledging
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...
occurs after four to five weeks, and the young can fly before they are fully grown. It is not known whether a second brood is raised.
Feeding
The African Crake feeds 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 including earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...
s, gastropods, molluscs and the adults and larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e of insects, especially 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, ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
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 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. Vertebrate
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
prey such as small frogs or fish may also be taken. Plant material is eaten, especially grass seeds, but also green shoots, leaves and other seeds. The crake searches for food both within vegetation and in the open, picking insects and seeds from the ground, turning over leaf litter, or digging with its bill in soft or very dry ground. It will chase faster moving prey, reach up to take food from plants, and wade to pluck food items from the water. Crop plants such as rice, maize and peas may sometimes be eaten, but this bird is not an agricultural pest species. It forages singly, in pairs or in family groups, sometimes in association with other grassland birds such as Great Snipe
Great Snipe
The Great Snipe, Gallinago media is a small stocky wader in the genus Gallinago.This bird's breeding habitat is marshes and wet meadows with short vegetation in north-eastern Europe including north-western Russia. Great Snipes are migratory, wintering in Africa...
s, Blue Quail
Blue Quail
The Blue Quail or African Blue Quail, is a species of bird in the Phasianidae family.-Geographic Range:The species ranges from Sierra Leone to Ethiopia, and south to Zambia, and eastward to Kenya, and is migratory...
s and Corn Crakes. Chicks are fed mainly on animal food. As with other rails, grit is swallowed to help break up food in the stomach.
Predators and parasites
Predators include the LeopardLeopard
The leopard , Panthera pardus, is a member of the Felidae family and the smallest of the four "big cats" in the genus Panthera, the other three being the tiger, lion, and jaguar. The leopard was once distributed across eastern and southern Asia and Africa, from Siberia to South Africa, but its...
, Serval
Serval
The serval , Leptailurus serval or Caracal serval, known in Afrikaans as Tierboskat, "tiger-forest-cat", is a medium-sized African wild cat. DNA studies have shown that the serval is closely related to the African golden cat and the caracal...
, cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s, the Black-headed Heron
Black-headed Heron
The Black-headed Heron is a wading bird of the heron family Ardeidae, common throughout much of sub-Saharan Africa and Madagascar. It is mainly resident but some west African birds move further north in the rainy season....
, Dark Chanting Goshawk
Dark Chanting Goshawk
The Dark Chanting Goshawk is a bird of prey in the family Accipitridae. The Accipitridae also include many other diurnal raptors such as kites, eagles and harriers....
, African Hawk-Eagle and Wahlberg's Eagle
Wahlberg's Eagle
The Wahlberg's Eagle is a bird of prey. It is about 55–60 cm in length and has a wingspan of 130–160 cm. Body mass is 1.04 kg for males and 1.3 kg for females on average. Like all eagles, it belongs to the family Accipitridae.Wahlberg's Eagle breeds in most of Africa south of...
. In South Africa, newly hatched chicks were taken by a Boomslang
Boomslang
The boomslang is a large venomous colubrid snake.-Taxonomy & etymology:It is currently the only species in its genus, although several species and subspecies have been described in the past...
. If surprised, an African Crake will leap vertically into the air before running away, a tactic believed to help it to evade snakes or terrestrial mammals.
Parasites of this species include tick
Tick
Ticks are small arachnids in the order Ixodida, along with mites, constitute the subclass Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians...
s of the family Ixodidae
Ixodidae
Ixodidae is a family of ticks containing the hard ticks.-Description:They are distinguished from the other main family of ticks, the soft ticks by the presence of a scutum or hard shield...
, and a feather mite
Feather mite
Feather mites are the members of diverse mite superfamilies:* superorder Acariformes** Psoroptidia*** Analgoidea*** Freyanoidea*** Pterolichoidea* superorder Parasitiformes** DermanyssoideaThey are ectoparasites on birds, hence the common name....
, Metanalges elongatus, of the subspecies M. e. curtus. The nominate form of the mite occurs thousands of kilometres away in New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
.
Status
The African Crake has a huge breeding range estimated at 15,700,000 km2 (4,500,000 mi2). Its population is unknown, but it is common in most of its range, and its numbers appear to be stable. It is therefore classed as Least ConcernLeast Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
. Overgrazing, agriculture and the loss of wetland and moist grassland have reduced the availability of suitable habitat in many areas, such as some parts of the southern KwaZulu-Natal coast which have been urbanised or planted with sugarcane. In other areas, grassland may have increased locally in recent years as woodland is cleared. This crake is considered to be good eating, and is killed for food in some regions. Despite these adverse factors, it appears to be under no real threat.
Although most rails in the Old World are covered by the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA), the African Crake is not listed even in Kenya, where it is considered "near-threatened". Like its relative, the Corn Crake, it is too terrestrial to be classed as a wetland species.