Chestnut Sparrow
Encyclopedia
The Chestnut Sparrow is a species of passerine
bird in the sparrow
family
Passeridae. It is the smallest member of the sparrow family, at about 11 cm (4.3 in) long. The breeding male has deep chestnut plumage
and the female and juvenile are duller in appearance. Like its closest relatives in the genus
Passer
, the Arabian Golden Sparrow
and the Sudan Golden Sparrow
, it is gregarious, and is found in arid areas. Ranging through the east of Africa from Darfur
to Tanzania
, it is found in dry savanna
, papyrus
swamps, and near human habitation. Adults and juveniles both feed mostly on grass seeds, and fly in flocks, often with other species of bird, to find food. It nests in trees, building its own domed nest
s, and also usurping the more elaborate nests of weavers.
lengths are about 4 cm (1.6 in), 1 cm (0.393700787401575 in), and 1.5 cm (0.590551181102362 in) respectively. The plumage
of the breeding male is mostly a deep shade of chestnut
in colour with black colouration on the face, wings, and tail. The chestnut colour is used descriptively in the common name. The breeding male is not easily confused with any other birds except the Chestnut Weaver
, which is substantially larger and has white on its wings. The breeding male's legs and feet are horn (pale grey) in colour. The non-breeding male Chestnut Sparrow has white flecking on the upperparts, and much of its plumage is buff or whitish with chestnut crescent markings, until the bright chestnut of the breeding plumage is exposed by wear. The non-breeding male's bill fades to a dusky-tipped horn, similar to that of females, but without dusky tones on the cutting edge of the mandible
(lower portion of beak
). Females have the same plumage pattern as males, though with somewhat duller colouration. The female has a grey head; buff supercilium
, chin, and throat; black and warm brown upperparts; and off-white underparts. The bill of the female is pale yellow with the tip and cutting edge of mandible dusky. Juveniles are dull grey with a brown back, a pale yellow supercilium, and a pale horn bill. Females and juveniles have hints of chestnut on their supercilium, shoulders, and throat, by which they may be distinguished from other sparrows, such as the Kenya Sparrow and the other rufous sparrows, which are common in much of the Chestnut Sparrow's range; or the House Sparrow
, which also occurs in parts of its range.
The basic call of the Chestnut Sparrow is a subdued chirp, with two recorded variations: a scolding threat call, rendered chrrrrit or chrrrrreeeerrrrrrrr and a chew chew flight call. Displaying males give a high twittering trill, rendered as tchiweeza tchiweeza tchi-tchi-tchi-tchi- see-see-see-seeichi.
in the Journal für Ornithologie
, as Sorella Emini Bey. Hartlaub gave it the specific name Emini Bey in honour of the explorer Emin Pasha
, who collected the type specimen in modern South Sudan
or Uganda
near Lado
, and it is occasionally given the eponymous common name
Emin Bey's Sparrow. Hartlaub's unusual spelling of its specific epithet as two words led some to spell the name emini or emini-bey. No subspecies are recognised, but one was described by British ornithologist George L. G. Van Someren in 1922 from northern Kenya, as Sorella eminibey guasso.
Hartlaub considered the Chestnut Sparrow's colouration and morphology
to be distinct enough to allocate it to its own monotypic genus, Sorella. Although several authors have followed Hartlaub's treatment, it is usually been placed in the genus Passer
. It is very similar to the two golden sparrows, from which it may have once been only clinally different. The male Arabian Golden Sparrow
is almost entirely gold-coloured, the male Chestnut Sparrow is mostly chestnut, and the male Sudan Golden Sparrow
is intermediate. British ornithologist Richard Meinertzhagen
considered these three species to be conspecific
; however, the range of the Sudan Golden Sparrow overlaps with that of the Chestnut Sparrow without any known interbreeding in a small area of Sudan
. These species are similar in their behaviour, which is adapted to the unpredictable conditions of their arid habitat. In particular, they and the Dead Sea Sparrow
share a courtship display
in which males quiver their wings above their body. This intense display is probably an adaptation to nesting in a clump of trees surrounded by similar habitat, where such an intense display may serve important purposes in keeping a colony together.
The Chestnut and golden sparrows have been seen as highly primitive among the genus Passer, only distantly related to the House Sparrow and the related "Palaearctic black-bibbed sparrows". In recognition of this they are sometimes placed in a separate genus or subgenus
Auripasser. The courtship display of the Dead Sea Sparrow was thought to have evolved separately in a similar environment from that of these species, in an example of convergent evolution
. However, studies of sparrow mitochondrial DNA
indicate that the Chestnut and golden sparrows are either derived from or are the closest relatives of the Palaearctic black-bibbed sparrows.
along a broad band of mostly lower country from Darfur through the Kordofan region, South Sudan, Somalia
, Uganda
, and Kenya
to north-central Tanzania. Its range also extends northeast into the southwest and Great Rift Valley
of Ethiopia
. Like the golden sparrows, it is sometimes nomadic when not breeding. Vagrants
have been recorded as far from their breeding range as Dar es Salaam
. It is found mostly in dry savanna
and in fields and villages, but unlike its relations the golden sparrows, it is sometimes found in swamps of papyrus (certain Cyperus
spp.). Its population has not been quantified, but it appears to be common across a very large range and it is assessed by the IUCN Red List
as Least Concern
for global extinction.
s and other weavers. Adults feed on grass seeds, and those near human habitations will also eat crumbs and other household scraps. Nestlings are fed mostly softer grass seeds, and small beetles are also recorded in their diet.
studied Chestnut Sparrows in a Grey-capped Social Weaver colony in an acacia
grove near Lake Magadi
in southern Kenya, and in 1969 he reported his findings in the ornithological journal The Ibis
. Payne found that Chestnut Sparrows only nested by usurping the nests of the social-weavers. After reporting this, and noting that the distribution of the Chestnut Sparrow closely coincides with that of the social-weavers of the genus Pseudonigrita
, Payne suggested that the Chestnut Sparrow was an obligate nest parasite (not a brood parasite
, like many Old World cuckoos and cowbird
s). Payne also noted in his paper that "Nest parasitism is generally thought to have been a stage in the evolutionary development of brood parasitism", an idea that remains accepted, and suggested the Chestnut Sparrow could be evolving towards obligate brood parasitism. However, it is known that besides parasitising the nests of weavers or using their abandoned nests, the Chestnut Sparrow also builds its own nests. Nests built by the Chestnut Sparrow, like most sparrow nests, are untidy domed structures which are made of grass and lined with feathers. Its breeding season
varies between different regions, following rains, and the breeding seasons of its hosts in areas where it parasitises nests; as a result it has been recorded breeding in every month of the year across its range.
At Payne's study locality the breeding season of the Chestnut Sparrow lagged behind that of its host. The sparrows began courting when the weavers started constructing their elaborate nests. Once the breeding season began, "the first impression was of the sparrows nesting and the Grey-capped Social Weavers unobtrusively skulking nearby". Males displayed around the new weaver nests, crouching, raising and quivering their wings in a shallow V, and giving a high, twittering trill. The males were chased by the social-weavers, but returned persistently, until joined by females. When a female came near a displaying male, the male would increase his rate of wing quivering, spread and depress his tail, and bow down his head, until his body formed an arc. This exaggerated display may be an adaptation related to pair formation in the absence of male nest-building, and it may also serve to focus attention in breeding colonies and keep the birds in a colony together, as colonies are in clumps of trees surrounded by similar habitat. During Payne's study, copulation was seen only in the acacias, around the social-weaver nests. Females would fly to displaying males and solicit copulation in typical sparrow fashion, crouching, quivering, and drooping their wings. When males saw displaying females, they would fly to them and mount them immediately. Males continued their wing quivering during copulation, and females would crouch, quiver, raise their head, and hold their tails horizontally. After a copulation the female would fly off and the male would continue displaying. During this courtship and afterwards, males and mated pairs would interfere with the social-weavers' nest building, until they drove the social-weavers out. During Payne's study period, "Chases and fights between the two species were seen nearly every minute of observation", and the male sparrows spent about a fifth of their day annoying the social-weavers. Little is recorded of incubation and fledging periods in the wild. In captivity the incubation period lasts for 18 to 19 days. Clutches
typically contain three or four eggs, which are ovular, mostly coloured white or bluish-white. Some observations indicate that nestlings are fed by the female alone.
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
bird in the sparrow
Sparrow
The sparrows are a family of small passerine birds, Passeridae. They are also known as true sparrows, or Old World sparrows, names also used for a genus of the family, Passer...
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...
Passeridae. It is the smallest member of the sparrow family, at about 11 cm (4.3 in) long. The breeding male has deep chestnut plumage
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 the female and juvenile are duller in appearance. Like its closest relatives in the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Passer
Passer
Passer is a genus of Old World sparrows. These sparrows are plump little brown or greyish birds often with black, yellow or white markings. Typically 10–20 cm long, they have short tails and stubby conical beaks...
, the Arabian Golden Sparrow
Arabian Golden Sparrow
The Arabian Golden Sparrow is a sparrow found in south west Arabia and also the coast of Somalia and Djibouti where it occurs in thorn savanna and scrub habitats. It is sometimes considered as a subspecies of the Sudan Golden Sparrow .- External links :*...
and the Sudan Golden Sparrow
Sudan Golden Sparrow
The Sudan Golden Sparrow is a small bird in the sparrow family, found to the south of the Sahara Desert in Africa. It is a popular cage bird, and in aviculture it is known as the Golden Song Sparrow...
, it is gregarious, and is found in arid areas. Ranging through the east of Africa from Darfur
Darfur
Darfur is a region in western Sudan. An independent sultanate for several hundred years, it was incorporated into Sudan by Anglo-Egyptian forces in 1916. The region is divided into three federal states: West Darfur, South Darfur, and North Darfur...
to 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...
, it is found in dry 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...
, papyrus
Cyperus
Cyperus is a large genus of about 600 species of sedges, distributed throughout all continents in both tropical and temperate regions. They are annual or perennial plants, mostly aquatic and growing in still or slow-moving water up to 0.5 m deep. The species vary greatly in size, with small species...
swamps, and near human habitation. Adults and juveniles both feed mostly on grass seeds, and fly in flocks, often with other species of bird, to find food. It nests in trees, building its own domed 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...
s, and also usurping the more elaborate nests of weavers.
Description
Like the other members of the sparrow family, the Chestnut Sparrow is a small, chunky songbird with a thick bill suited for its diet of seeds. At 10.5 to 11.5 cm (4.1 to 4.5 in) in length, it is the smallest member of the sparrow family. It weighs between 12 gram (0.423287545261344 oz) and 17 gram (0.599657355786903 oz). Wing length ranges from 6 to 6.5 cm (2.4 to 2.6 in) in males and from 5.7 to 6 cm (2.2 to 2.4 in) in females. The tail, bill, and tarsusTarsus (skeleton)
In tetrapods, the tarsus is a cluster of articulating bones in each foot situated between the lower end of tibia and fibula of the lower leg and the metatarsus. In the foot the tarsus articulates with the bones of the metatarsus, which in turn articulate with the bones of the individual toes...
lengths are about 4 cm (1.6 in), 1 cm (0.393700787401575 in), and 1.5 cm (0.590551181102362 in) respectively. The plumage
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...
of the breeding male is mostly a deep shade of chestnut
Chestnut (color)
Chestnut, also known as Indian red, is a color, a medium brownish shade of red, and is named after the nut of the chestnut tree.As Indian red, it is named after the red laterite soil found in India. It is thus an earth tone as well as a red. It is composed of naturally occurring iron oxides. Other...
in colour with black colouration on the face, wings, and tail. The chestnut colour is used descriptively in the common name. The breeding male is not easily confused with any other birds except the Chestnut Weaver
Chestnut Weaver
The Chestnut Weaver is a species of bird in the Ploceidae family.It is found in Angola, Botswana, Eritrea, Ethiopia, Kenya, Namibia, Somalia, Sudan, Tanzania, and Uganda.-References:...
, which is substantially larger and has white on its wings. The breeding male's legs and feet are horn (pale grey) in colour. The non-breeding male Chestnut Sparrow has white flecking on the upperparts, and much of its plumage is buff or whitish with chestnut crescent markings, until the bright chestnut of the breeding plumage is exposed by wear. The non-breeding male's bill fades to a dusky-tipped horn, similar to that of females, but without dusky tones on the cutting edge of the mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
(lower portion of beak
Beak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
). Females have the same plumage pattern as males, though with somewhat duller colouration. The female has a grey head; buff supercilium
Supercilium
The supercilium is a plumage feature found on the heads of some bird species. It is a stripe which runs from the base of the bird's beak above its eye, finishing somewhere towards the rear of the bird's head. Also known as an "eyebrow", it is distinct from the eyestripe, which is a line which runs...
, chin, and throat; black and warm brown upperparts; and off-white underparts. The bill of the female is pale yellow with the tip and cutting edge of mandible dusky. Juveniles are dull grey with a brown back, a pale yellow supercilium, and a pale horn bill. Females and juveniles have hints of chestnut on their supercilium, shoulders, and throat, by which they may be distinguished from other sparrows, such as the Kenya Sparrow and the other rufous sparrows, which are common in much of the Chestnut Sparrow's range; or the House Sparrow
House Sparrow
The House Sparrow is a bird of the sparrow family Passeridae, found in most parts of the world. One of about 25 species in the genus Passer, the House Sparrow occurs naturally in most of Europe, the Mediterranean region, and much of Asia...
, which also occurs in parts of its range.
The basic call of the Chestnut Sparrow is a subdued chirp, with two recorded variations: a scolding threat call, rendered chrrrrit or chrrrrreeeerrrrrrrr and a chew chew flight call. Displaying males give a high twittering trill, rendered as tchiweeza tchiweeza tchi-tchi-tchi-tchi- see-see-see-seeichi.
Taxonomy
This species was first described in 1880, by Gustav HartlaubGustav Hartlaub
Karel Johan Gustav Hartlaub was a German physician and ornithologist.Hartlaub was born in Bremen, and studied at Bonn and Berlin before graduating in medicine at Göttingen. In 1840, he began to study and collect exotic birds, which he donated to the Bremen Natural History Museum. He described some...
in the Journal für Ornithologie
Journal of Ornithology
The Journal of Ornithology is a scientific journal published by Springer Science+Business Media on behalf of the Deutsche Ornithologen-Gesellschaft. It was founded by Jean Cabanis in 1853, becoming the official journal of the Deutsche Ornithologen-Gesellschaft in 1854....
, as Sorella Emini Bey. Hartlaub gave it the specific name Emini Bey in honour of the explorer Emin Pasha
Emin Pasha
Mehmed Emin Pasha — he was born Isaak Eduard Schnitzer and baptized Eduard Carl Oscar Theodor Schnitzer — was a physician, naturalist, and governor of the Egyptian province of Equatoria on the upper Nile...
, who collected the type specimen in modern South Sudan
South Sudan
South Sudan , officially the Republic of South Sudan, is a landlocked country located in the Sahel region of northeastern Africa. It is also part of the North Africa UN sub-region. Its current capital is Juba, which is also its largest city; the capital city is planned to be moved to the more...
or Uganda
Uganda
Uganda , officially the Republic of Uganda, is a landlocked country in East Africa. Uganda is also known as the "Pearl of Africa". It is bordered on the east by Kenya, on the north by South Sudan, on the west by the Democratic Republic of the Congo, on the southwest by Rwanda, and on the south by...
near Lado
Lado, South Sudan
Lado is a settlement in Central Equatoria State in South Sudan, on the west bank of the White Nile.When General Gordon was appointed governor of the Egyptian territory of Equatoria in 1874, he moved his capital from Gondokoro to Lado, which had a healthier climate.In 1878 Emin Pasha was appointed...
, and it is occasionally given the eponymous common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
Emin Bey's Sparrow. Hartlaub's unusual spelling of its specific epithet as two words led some to spell the name emini or emini-bey. No subspecies are recognised, but one was described by British ornithologist George L. G. Van Someren in 1922 from northern Kenya, as Sorella eminibey guasso.
Hartlaub considered the Chestnut Sparrow's colouration 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....
to be distinct enough to allocate it to its own monotypic genus, Sorella. Although several authors have followed Hartlaub's treatment, it is usually been placed in the genus Passer
Passer
Passer is a genus of Old World sparrows. These sparrows are plump little brown or greyish birds often with black, yellow or white markings. Typically 10–20 cm long, they have short tails and stubby conical beaks...
. It is very similar to the two golden sparrows, from which it may have once been only clinally different. The male Arabian Golden Sparrow
Arabian Golden Sparrow
The Arabian Golden Sparrow is a sparrow found in south west Arabia and also the coast of Somalia and Djibouti where it occurs in thorn savanna and scrub habitats. It is sometimes considered as a subspecies of the Sudan Golden Sparrow .- External links :*...
is almost entirely gold-coloured, the male Chestnut Sparrow is mostly chestnut, and the male Sudan Golden Sparrow
Sudan Golden Sparrow
The Sudan Golden Sparrow is a small bird in the sparrow family, found to the south of the Sahara Desert in Africa. It is a popular cage bird, and in aviculture it is known as the Golden Song Sparrow...
is intermediate. British ornithologist Richard Meinertzhagen
Richard Meinertzhagen
Colonel Richard Henry Meinertzhagen CBE DSO was a British soldier, intelligence officer and ornithologist.- Background and youth :Meinertzhagen was born into a socially connected, wealthy British family...
considered these three species to be conspecific
Conspecificity
Conspecificity is a concept in biology. Two or more individual organisms, populations, or taxa are conspecific if they belong to the same species....
; however, the range of the Sudan Golden Sparrow overlaps with that of the Chestnut Sparrow without any known interbreeding in a small area of Sudan
Sudan
Sudan , officially the Republic of the Sudan , is a country in North Africa, sometimes considered part of the Middle East politically. It is bordered by Egypt to the north, the Red Sea to the northeast, Eritrea and Ethiopia to the east, South Sudan to the south, the Central African Republic to the...
. These species are similar in their behaviour, which is adapted to the unpredictable conditions of their arid habitat. In particular, they and the Dead Sea Sparrow
Dead Sea Sparrow
The Dead Sea Sparrow , as its name suggests, is a breeding bird around the River Jordan, Dead Sea, and into Iraq, Iran and western Afghanistan. Breeding recorded in Cyprus but is probably extinct there now...
share a courtship display
Courtship display
Courtship display is a special, sometimes ritualised, set of behaviours which some animals perform as part of courtship. Courtship behaviours can include special calls, postures, and movements, and may involve special plumage, bright colours or other ornamentation. A good example is the 'dancing'...
in which males quiver their wings above their body. This intense display is probably an adaptation to nesting in a clump of trees surrounded by similar habitat, where such an intense display may serve important purposes in keeping a colony together.
The Chestnut and golden sparrows have been seen as highly primitive among the genus Passer, only distantly related to the House Sparrow and the related "Palaearctic black-bibbed sparrows". In recognition of this they are sometimes placed in a separate genus or subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
Auripasser. The courtship display of the Dead Sea Sparrow was thought to have evolved separately in a similar environment from that of these species, in an example of convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
. However, studies of sparrow mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
indicate that the Chestnut and golden sparrows are either derived from or are the closest relatives of the Palaearctic black-bibbed sparrows.
Distribution and habitat
The Chestnut Sparrow is found in East AfricaEast Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
along a broad band of mostly lower country from Darfur through the Kordofan region, South Sudan, 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...
, Uganda
Uganda
Uganda , officially the Republic of Uganda, is a landlocked country in East Africa. Uganda is also known as the "Pearl of Africa". It is bordered on the east by Kenya, on the north by South Sudan, on the west by the Democratic Republic of the Congo, on the southwest by Rwanda, and on the south by...
, and 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...
to north-central Tanzania. Its range also extends northeast into the southwest and Great Rift Valley
Great Rift Valley
The Great Rift Valley is a name given in the late 19th century by British explorer John Walter Gregory to the continuous geographic trench, approximately in length, that runs from northern Syria in Southwest Asia to central Mozambique in South East Africa...
of 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...
. Like the golden sparrows, it is sometimes nomadic when not breeding. Vagrants
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...
have been recorded as far from their breeding range as Dar es Salaam
Dar es Salaam
Dar es Salaam , formerly Mzizima, is the largest city in Tanzania. It is also the country's richest city and a regionally important economic centre. Dar es Salaam is actually an administrative province within Tanzania, and consists of three local government areas or administrative districts: ...
. It is found mostly in dry 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...
and in fields and villages, but unlike its relations the golden sparrows, it is sometimes found in swamps of papyrus (certain Cyperus
Cyperus
Cyperus is a large genus of about 600 species of sedges, distributed throughout all continents in both tropical and temperate regions. They are annual or perennial plants, mostly aquatic and growing in still or slow-moving water up to 0.5 m deep. The species vary greatly in size, with small species...
spp.). Its population has not been quantified, but it appears to be common across a very large range and it is assessed by 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...
as Least Concern
Least 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...
for global extinction.
Behaviour
Chestnut Sparrows are gregarious, and are only occasionally found away from flocks. They frequently associate with queleaQuelea
Quelea is a small genus of passerine birds that belongs to the weaver family Ploceidae, confined to Africa. These are small-sized, sparrow- or finch-like gregarious birds, with bills adapted to eating seeds...
s and other weavers. Adults feed on grass seeds, and those near human habitations will also eat crumbs and other household scraps. Nestlings are fed mostly softer grass seeds, and small beetles are also recorded in their diet.
Breeding
The nesting behaviour of Chestnut Sparrow has been the subject of confusion. Early reports described the Chestnut Sparrow's nest as being a typical sparrow nest built in a tree; later it was reported that Chestnut Sparrows had elaborate nests like those of weavers. In 1967, the ornithologist Robert B. PayneRobert Payne (ornithologist)
Robert Berkeley Payne is an ornithologist, professor and curator at the Museum of Zoology and Department of Ecology and Evolutionary Biology, University of Michigan.-Academic background:...
studied Chestnut Sparrows in a Grey-capped Social Weaver colony in an 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...
grove near Lake Magadi
Lake Magadi
Lake Magadi is the southernmost lake in the Kenya Rift Valley, lying in a catchment of faulted volcanic rocks, north of Tanzania's Lake Natron. During the dry season, it is 80% covered by soda and is well known for its wading birds, including flamingos....
in southern Kenya, and in 1969 he reported his findings in the ornithological journal The Ibis
Ibis (journal)
Ibis, subtitled the International Journal of Avian Science, is the peer-reviewed scientific journal of the British Ornithologists' Union. Topics covered include ecology, conservation, behaviour, palaeontology, and taxonomy of birds. The editor-in-chief is Paul F. Donald. The journal is published by...
. Payne found that Chestnut Sparrows only nested by usurping the nests of the social-weavers. After reporting this, and noting that the distribution of the Chestnut Sparrow closely coincides with that of the social-weavers of the genus Pseudonigrita
Pseudonigrita
Pseudonigrita is a genus of bird in the Ploceidae family.It contains the following species:* Grey-capped Social Weaver * Black-capped Social Weaver...
, Payne suggested that the Chestnut Sparrow was an obligate nest parasite (not a brood parasite
Brood parasite
Brood parasites are organisms that use the strategy of brood parasitism, a kind of kleptoparasitism found among birds, fish or insects, involving the manipulation and use of host individuals either of the same or different species to raise the young of the brood-parasite...
, like many Old World cuckoos and cowbird
Cowbird
Cowbirds are birds belonging to the genus Molothrus in the family Icteridae. They are brood parasitic New World birds which are unrelated to the Old World cuckoos, one of which, the Common Cuckoo, is the best-known brood parasitic bird....
s). Payne also noted in his paper that "Nest parasitism is generally thought to have been a stage in the evolutionary development of brood parasitism", an idea that remains accepted, and suggested the Chestnut Sparrow could be evolving towards obligate brood parasitism. However, it is known that besides parasitising the nests of weavers or using their abandoned nests, the Chestnut Sparrow also builds its own nests. Nests built by the Chestnut Sparrow, like most sparrow nests, are untidy domed structures which are made of grass and lined with feathers. Its breeding season
Breeding season
The breeding season is the most suitable season, usually with favourable conditions and abundant food and water, for breeding among some wild animals and birds . Species with a breeding season have naturally evolved to have sexual intercourse during a certain time of year in order to achieve the...
varies between different regions, following rains, and the breeding seasons of its hosts in areas where it parasitises nests; as a result it has been recorded breeding in every month of the year across its range.
At Payne's study locality the breeding season of the Chestnut Sparrow lagged behind that of its host. The sparrows began courting when the weavers started constructing their elaborate nests. Once the breeding season began, "the first impression was of the sparrows nesting and the Grey-capped Social Weavers unobtrusively skulking nearby". Males displayed around the new weaver nests, crouching, raising and quivering their wings in a shallow V, and giving a high, twittering trill. The males were chased by the social-weavers, but returned persistently, until joined by females. When a female came near a displaying male, the male would increase his rate of wing quivering, spread and depress his tail, and bow down his head, until his body formed an arc. This exaggerated display may be an adaptation related to pair formation in the absence of male nest-building, and it may also serve to focus attention in breeding colonies and keep the birds in a colony together, as colonies are in clumps of trees surrounded by similar habitat. During Payne's study, copulation was seen only in the acacias, around the social-weaver nests. Females would fly to displaying males and solicit copulation in typical sparrow fashion, crouching, quivering, and drooping their wings. When males saw displaying females, they would fly to them and mount them immediately. Males continued their wing quivering during copulation, and females would crouch, quiver, raise their head, and hold their tails horizontally. After a copulation the female would fly off and the male would continue displaying. During this courtship and afterwards, males and mated pairs would interfere with the social-weavers' nest building, until they drove the social-weavers out. During Payne's study period, "Chases and fights between the two species were seen nearly every minute of observation", and the male sparrows spent about a fifth of their day annoying the social-weavers. Little is recorded of incubation and fledging periods in the wild. In captivity the incubation period lasts for 18 to 19 days. Clutches
Clutch (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...
typically contain three or four eggs, which are ovular, mostly coloured white or bluish-white. Some observations indicate that nestlings are fed by the female alone.