Cape Sparrow

a male Cape Sparrow

The Cape Sparrow or Mossie (Passer melanurus) is a species of passerine bird in the sparrow family. Brightly coloured and distinctive, it is coloured grey, brown, and chestnut, with some black and white markings on the male. It is found in southern Africa, where it inhabits savanna, cultivated areas, and towns.

The Cape Sparrow is brightly coloured and distinctive, a medium-sized sparrow at 14 to 16 centimetres (5.5 to 6.3 in). The breeding male has a mostly black head, broken by a broad white on each side band curling from behind the eye to the throat. On the throat a narrow black band connects the black bib of the breast to black of the head. Underparts are greyish, darker on the flanks. back of the male's neck is dark grey, and its back and shoulders are bright chestnut. The male has a white and a black wing bar below its shoulders, and flight feathers and tail streaked grey and black. The female is plumaged like the male, but is duller and has a grey head with a different pattern from the male. The juvenile is like the female, but young males show black on the head from an early age.

The Cape Sparrow's vocalisations are chirps similar to those of the House Sparrow, but much more musical and mellow. The basic call is used in flight and while perching socially and transcribed as chissip, chirrup, chreep, or chirrichup. A call used by the male to advertise nest ownership is transcribed as tweeng or twileeng. Distinctive and loud, this call sometimes becomes a jerky and repetitive song, transcibed as chip cheerup, chip cheerup.

The Cape Sparrow was first described by Philipp Ludwig Statius Müller in 1776. It is a member of the genus Passer. Within this genus its relations have generally been regarded as obscure. Mitochondrial DNA studies, however, have strongly suggested that the Cape Sparrow is the earliest offshoot, or the most basal member of this genus.

The Cape Sparrow has three subspecies. The nominate subspecies Passer melanurus melanurus is found in eastern South Africa, east to the west of Free State, and the subspecies vicinus, which is sometimes merged with melanurus, east from Free State to the Eastern Cape and Lesotho. The subspecies damarensis ranges from the extreme southern coastal areas of Angola into Namibia, Botswana and the extreme west of Zimbabwe, as well as northern South Africa.

The Cape Sparrow inhabits southern Africa from Angola south to South Africa and east to Lesotho. Its original habitats were the semi-arid savanna, thornveld, and light woodland typical of southern Africa. When settled agriculture arrived in its range about a thousand years ago, it adapted to cultivated land. Since then it has moved into towns.

While it occurs in urban centers, it prefers parks, gardens, and other open spaces, and has a low reproductive success in more built-up areas. The Cape Sparrow prefers habitats with an annual rainfall of less than 75 centimetres (30 in), though in desert areas it is usually found near watercourses or watering holes. When vineyards in the southwest Cape started letting weeds grow between vines to conserve moisture around 1956, the Cape Sparrow moved in. Cape Sparrows quickly exhausted the seeds and started eating the grapes. The Cape Sparrow is now a serious pest in vineyards, but in these areas they have such a low reproductive success their populations cannot be maintained without immigration.

In towns, the Cape Sparrow competes with both the native Southern Grey-headed Sparrow and the introduced House Sparrow. Since it is more established around humans in its range than either, it successfully competes with both species, though they may exclude it from nesting in holes.

The Cape Sparrow is social, living in flocks, and usually breeding in colonies. Away from humans it is nomadic, and forms flocks of up to 200 birds. In cultivated and built up areas, it forms smaller flocks where food is provided for livestock or birds. In such places, it associates with other seed-eating birds, such as the House Sparrow, the Cape Weaver, and Euplectes birds. Birds from urban areas form flocks seasonally and fly out to nearby countryside to feed on ripening grain, returning at night to roost. Outside the breeding season, birds in uncultivated areas roost in old nests or dense bushes, but the birds of farmland and towns build special nests for roosting
.
An unusual social behaviour has been described from Cape Sparrows in Johannesburg. Groups of 20–30 birds separate from larger flocks and stand close together on the ground with tails on the ground and heads held high. These groups sometimes move in an unconcerted fashion by hopping slowly. Often birds will fly up and hover 30 to 60 centimetres (12 to 24 in) above the ground. During these gatherings birds are silent and are never antagonistic. This behaviour's significance is unknown, and it is not reported in any other sparrow.

The Cape Sparrow mostly eats seeds. The larger seeds of cereals, wild grasses, and other small plants are preferred, with wheat and khakiweed (Alternanthera caracasana) being favourites. Buds and soft fruits are also taken, causing considerable damage to agriculture. Insects are eaten, and nestlings seem to fed exclusively on caterpillars. The Cape Sparrow eats the soft shoots of plants, and probes in aloes for nectar, but these habits are not important sources of food.

The Cape Sparrow usually breeds in loose colonies of 50–100 birds. 10 to 20 percent of the pairs in each population nest away from colonies, for unknown reasons. It seems pairs are formed in the non-breeding flocks, but it is not known how pairs are formed, or if the pair bond is for life. Once ready to breed, newly mated pairs look for a suitable nesting site, spending mornings searching, and returning to their flock in the afternoon. Once a site has been selected, both birds begin to build their nest. Other pairs seeking a nest site join them, and in this matter a colony forms quickly.

The Cape Sparrow utilises a variety of nesting sites, including holes as well as open locations. Bushes and trees, especially acacias, seem to be preferred. Holes and other covered sites are chosen less frequently. Nests have been recorded from the eaves of buildings, on creepers on walls, in holes in earth banks, and in holes in haystacks. Sometimes the Cape Sparrow nests in the disused nests of other birds, such as weavers and swallows. Pairs that nest away from colonies usually choose low bushes or utility poles as nesting sites.

Nests are placed at least a metre above the ground, and can be only a few centimetres apart in colonies. Only the nest and its very close vicinity are defended as a territory. Males defend their territory with threatening postures, and sometimes by fighting with bills on the ground.

Nests built in the open are large and untidy domed structures. Nests are built mainly of dry grass and twigs, with a soft lining of plant down. Any leaves or thorns present in a nest tree are worked into the nest. In cavity nests, the hole is simply filled with a shapeless mass of grass with a cup of soft material containing the eggs on the inside. When the disused nests of weavers are utilised, they are simply given a soft lining. The nest entrance is in the side, and is sometimes extended into a funnel. The male and the female construct the nest together, keeping close when finding material and weaving it together.

The courtship display is poorly recorded. J. Denis Summers-Smith observed a display in which the male hopped beside the female in a tree, drooping its wings and ruffling the chestnut-coloured feathers on its back. Groups of two or more males have been observed chasing a female. In the House Sparrow a similar display exists, in which a female who is not ready to copulate is chased by her mate, who is joined by other males. It is not known if the display in the Cape Sparrow has a similar significance. When ready to mate, the female crouches in solicitation and is mounted by the male.

Clutches contain between two and six eggs, typically three or four. Clutches are larger further south, and during the peak of the breeding season.

Both birds of a pair incubate the eggs during the day, switching every ten or fifteen minutes. At night, only the female incubates the eggs, while the male roosts outside or in the nest. In pairs breeding outside of colonies, birds leave the nest to make room for their mates upon hearing their mates approaching. Among colonial pairs, the incubating bird waits until its partner arrives in the nest, to prevent other birds from entering the nest. Incubation seems to begin before the clutch is complete, and lasts 12–24 days. The young of a clutch hatch over two or three days and are brooded until their feathers develop and eyes open five days after hatching. The young are fed on insects until they fledge 16 to 25, typically 17, days after hatching. After this they are fed for one or two weeks. While feeding nestlings, the female is dominant over the male.