|Male in Victoria|
|Female in England
Nesting birds calling (help·info)
|Native range in dark green and introduced range in light green.|
Fringilla domestica Linnaeus, 1758
The House Sparrow (Passer domesticus) is a species of passerine bird in the sparrow family Passeridae. It occurs naturally in most of Europe, the Mediterranean region, and much of Asia. It has also followed humans all over the world and has been intentionally or accidentally introduced to most of the Americas, sub-Saharan Africa, New Zealand and Australia as well as urban areas in other parts of the world. It is now the most widely distributed wild bird on the planet. It is strongly associated with human habitations, but it is not the only sparrow species found near houses. In the United States it is also colloquially known as the English Sparrow to distinguish it from American sparrows.
The House Sparrow is a chunky bird, ranging from 14–18 centimetres (5.5–7.1 in) in length, and from 24–39.5 grams (0.85–1.4 oz) in mass, depending on sex, subspecies, and environment. Females average smaller than males, and southern birds are smaller than their northern counterparts, though altitude may be equally important.
Like most of the members of its genus, the House Sparrow is sexually dimorphic. The male's mantle and upper back are a warm brown, broadly streaked with black, while the lower back, rump and uppertail coverts are a greyish-brown. The crown, cheeks and underparts are pale grey, with black on the throat, upper breast and between the bill and eyes. The bill in summer is blue-black, and the legs are brown. In winter the plumage is dulled by pale edgings, and the bill is yellowish brown. The black throat patch on the males is variable in size, and the size of that patch or badge may be correlated with the aggressiveness, suggesting that it is a signal to show dominance in a social situation. The female has no black on head or throat, nor a grey crown; her upperparts are streaked with brown. The juveniles are deeper brown, and the white is replaced by buff; the beak is pink to dull yellow. The House Sparrow's range overlaps extensively with that of the smaller and more slender Eurasian Tree Sparrow, which has a chestnut and not grey crown, two distinct wing bars, and a black patch on each cheek.
All of the House Sparrow's calls are variations on its short and incessant double chirp call note "chirrup" or "philip". This note is made as a contact call by birds away from their nesting area, or by males as a proclamation of nest ownership or to invite pairing; this call led to the now obsolete folk name of "Phillip Sparrow". House Sparrows give also give this call in what is known as "social singing", while resting between periods of feeding, or while roosting. In the breeding season this call becomes what is called an "ecstatic call", which is similar to a song, as it is uttered by the male at great speed. Young birds, especially captive ones, also give a true song, a warbling similar to that of the European Greenfinch. Aggressive male House Sparrows give a trilled version of their call, transcribed as "chur-chur-r-r-it-it-it-it". This call is also used by females in the breeding season, to establish dominance over males while displacing them to feed young or incubate eggs. House Sparrows give a nasal alarm call, the basic sound of which is transcribed as "quer". When in great distress, they give a shrill "chree" call. Another House Sparrow vocalisation is what has been described as an "appeasement call," given to inhibit aggression, usually by a mated pair. These vocalisations are not unique to the House Sparrow, but are shared with only minor variations by most sparrows.
The House Sparrow is part of the Old World sparrow genus Passer, which contains 15-25 species, depending on the authority. Its members are typically found in open, lightly wooded, habitats. Most species in the genus are between 10–20 centimetres (3.9–7.9 in) long, dull-coloured birds with short square tails and stubby conical beaks. They are mostly ground-feeding seed-eaters, although they also consume invertebrates, especially when breeding. The House Sparrow is part of a group with Mediterranean origins, and its closest relatives are the Spanish and Italian Sparrows.
The bird's English and scientific names have the same meaning. The Latin word passer, like the English word "sparrow," was a term for small active birds, coming from a root word referring to speed. The Latin word domesticus means "of the house," like the common name a reference to the long association between the sparrow and humans. The House Sparrow was named by Carl Linnaeus, the founder of modern biological taxonomy, as Fringilla domestica. Later the genus Fringilla came to be used only for the Chaffinch and its relatives, and the sparrows came to be placed in the genus Passer created by French zoologist Mathurin Jacques Brisson in 1760.
A large number of subspecies, distinguished mostly by their plumage, have been named, and ten are generally recognised. These subspecies are divided into two groups, the Palearctic domesticus group, and the Oriental indicus group. The indicus group is distinguished by white cheeks, bright colouration on the crown, a smaller bill, and a longer black bib. Migratory birds of the subspecies bactrianus in the indicus group were recorded breeding beside with the subspecies domesticus without hybridising in the 1970s, so the Soviet scientists E. I. Gavrilov and M. N. Korelov proposed indicus to be a separate species. The subspecies biblicus and its relatives are sometimes considered a third group.
In North America and Hawaii, birds are differentiated by latitude and climate, though it is not clear how much this is caused by evolution or by environment. Similar observations have been made in New Zealand, and in South Africa. Some authors have considered introduced House Sparrow populations to be worthy of subspecies status, such as Harry Church Oberholser, who gave the subspecies name plecticus to the sparrows of western North America in his 1974 Bird Life of Texas.
In parts of the Mediterranean basin, the taxonomy and distribution of the sparrows is complicated by the presence of the "willow sparrows." The common type of willow sparrow is the Spanish Sparrow, which resembles the House Sparrow in many respects. It frequently prefers wetter habitats than the House Sparrow, and it is often colonial and nomadic. In most of the Mediterranean, either the House or the Spanish sparrow occurs, or both, with some degree of hybridisation. In North Africa, the two species hybridise extensively, forming highly variable mixed populations with a full range of characters from pure House Sparrows to pure Spanish Sparrows and everything between. In much of Italy there is a type of sparrow apparently intermediate between the House and Spanish sparrows, known as the Italian Sparrow. It resembles a hybrid between the two species, and is in other respects intermediate. Its specific status and origin are the subject of much debate. In the Alps of Italy, the Italian Sparrow integrades over a roughly 20 kilometres (12 mi) strip with the House Sparrow, but to the south it integrades over the southern half of Italy and some Mediterranean islands with the Spanish Sparrow. On the Mediterranean islands of Malta, Gozo, Crete, Rhodos, and Karpathos, there are other apparently intermediate birds of unknown status.
The House Sparrow originated in the Middle East, and it spread along with agriculture to most of Eurasia, and parts of North Africa. In much of eastern Asia the Eurasian Tree Sparrow fills its role as an urban bird, and it is uncommon. Since the middle of the nineteenth century, it has spread throughout much of the world, mostly due to deliberate introductions but also through natural dispersal and seaborne travel. The House Sparrow has also greatly extended its range in northern Eurasia since the 1850s, and continues to do so, as is shown by the colonisations, both around 1990, of Iceland and Rishiri Island.
Its introduced range encompasses most of North America, Central America, southern South America, southern Africa, part of West Africa, Australia, New Zealand, and islands throughout the world, making it the most widely distributed wild bird on the planet. The House Sparrow has become highly successful in most parts of the world where it has been introduced. This is due to its early adaptation to living with humans, and its adaptability to a wide range of conditions. Other factors may include its robust immune response. In many parts of the world it has become a pest, and a threat to many native bird species. The first of many successful introductions to North America occurred when fifty pairs from England were released in New York, by the commissioners of Central Park around 1852. Today its range is spread from Northwest Territories to Darién Province, and it is one of the most abundant birds in North America, with a population estimated at approximately 150 million in the 1940s. The House Sparrow was first introduced to Australia in 1863 at Melbourne and it is a major pest throughout eastern Australia, but has been prevented from establishing itself in Western Australia where every House Sparrow found in the state is killed. House Sparrows were introduced in New Zealand in 1859, and from there reached many of the Pacific islands, including Hawaii. In southern Africa birds of both the European subspecies domesticus and the Indian subspecies indicus were introduced around 1900. Birds of domesticus ancestry are confined to a few towns, while indicus birds have spread rapidly, reaching Tanzania in the 1980s. Despite this success, its native relatives successfully compete with it. In South America, it was introduced in Argentina, and has spread as far north as the fringes of Amazonia.
The House Sparrow is closely associated with human habitations and cultivation. It is not the obligate commensal of humans some have suggested it is, as Central Asian birds breed away from humans in open country, leaving towns to the Eurasian Tree Sparrow, and birds elsewhere are found away from humans. The only habitats in which the House Sparrow is not found are dense forest and cold open country, such as tundra. It is, however, well adapted to living around humans. It frequently lives and even breeds indoors, especially in factories, warehouses, and zoos. It has been recorded breeding in a coal mine 640 metres (2,100 ft) below ground, and feeding on the Empire State Building's observation deck at night. It reaches its greatest densities in urban centers, but its reproductive success is greater in suburbs, where insects are more abundant. It tolerates a variety of climates, but prefers drier conditions, especially in moist tropical countries. It has a number of adaptations to dry areas, including a high salt tolerance and an ability to survive without water by ingesting berries.
The House Sparrow's interactions with the Eurasian Tree Sparrow are complex. In most areas where the two species occur together, the House Sparrow breeds in urban areas while the smaller Eurasian Tree Sparrow nests in the countryside. Where trees are in short supply, as in Mongolia, both sparrows may utilise man-made structures as nest sites. The Eurasian Tree Sparrow is rural in Europe, but is an urban bird in eastern Asia; in southern and central Asia, both Passer species may be found around towns and villages. In Australia, the Eurasian Tree Sparrow is largely an urban bird, and it is the House Sparrow which utilises more natural habitats.
The House Sparrow is a very social bird. It is gregarious at all seasons when feeding, it roosts communally, and its nests are usually placed together in clumps, with actual colonial nesting being recorded. Other social activities include dust and water bathing, and "social singing", in which birds call together in bushes. For the larger part it is sedentary, though two subspecies, bactrianus and parkini, are entirely migratory. There also is limited migration in many mountain areas, and within sedentary populations a few birds migrate each year. Unlike other migratory House Sparrows, bactrianus and parkini birds prepare for migration by putting on weight. Non-breeding House Sparrow nest in large groups in trees, gathering some time before and engaging in "social singing." At feeding stations and at the nest, the female House Sparrow is dominant over the male, despite her smaller size.
As an adult, the House Sparrow is largely a granivorous species, eating the seeds of grains and weeds, but it is opportunistic and adaptable, and eats whatever foods are available. Several studies of the House Sparrow in temperate agricultural areas have shown the proportion of seeds in its diet to be about 90 percent. House Sparrows will eat almost any seeds, but where they have a choice of grains, they prefer oats and wheat. In urban areas, the House Sparrow feeds largely on food provided directly or indirectly by humans, such as bread, though it prefers raw seeds. The House Sparrow also eats berries and fruits, and in arid areas it can survive without water by ingesting moisture with berries.
Another important part of the House Sparrow diet is animal food, chiefly insects, of which beetles, caterpillars, dipteran flies, and aphids are especially important. Other animal foods include various non-insect arthropods, molluscs and crustaceans where available, earthworms, and vertebrates such as lizards, frogs, and mice. The House Sparrow has a habit of fly-catching insects in the early spring and early autumn, and a habit of tearing flowers, especially yellow ones in the spring. The House Sparrow requires grit to digest its food of hard seeds. Grit can be either stone, often grains of masonry, or the shells of eggs or snails. Oblong and rough grains are preferred.
Nestling House Sparrows are mostly on insects until about fifteen days after hatching. They also are fed small quantities of wheat and weed seeds, spiders, and grit. In most places, grasshoppers and crickets are most important. True bugs, ants, sawflies, and beetles are also important, but House Sparrows will take advantage of whatever food is most abundant to feed their nestlings.
More unusual foraging behaviours of the House Sparrow include taking insects from car radiators, nectar robbing kowhai flowers, catching periodical cicadas, and opening automatic doors to enter supermarkets.
The House Sparrow first attempts to breed in the breeding season immediately following its hatching. Some birds breeding for the first time, especially in tropical areas, are only a few months old, and retain juvenile plumage. Such young birds usually are not successful in breeding. Reproductive success increases with age, due principally to changes in the timing of breeding; older birds breed earlier in the season than younger birds do, and fledge more young.
The House Sparrow is monogamous, and it typically mates for life. Birds from pairs often engage in extra-pair copulations, with about 15 percent of House Sparrow fledgelings being unrelated to their mother's mate. Bigamy occurs, and is mostly limited by aggression between females. Male House Sparrows guard their mates carefully before breeding to avoid being cuckolded. Lost mates are quickly replaced during the breeding season, since many birds do not find a nest and a mate. Some of these birds serve as helpers for mated pairs, and usually such birds are chosen to replace lost mates. The formation of a pair and the bond between the two birds is related to the holding of a nest site, though birds of a pair can recognise each other away from the nest. Before the breeding season, unmated males take up a nesting site and call incessantly to attract females. When a female approaches a displaying male, the male displays by drooping and shivering his wings, pushing up his head, raising and spreading his tail, and displaying his black bib. The male then tries to mate with the female, who adopts a threatening posture and attacks him before flying away. The male then flies after the female and displays in front of her, attracting other males, who also display to her. These other males usually do not mate with the female, though this has been recorded once. When the female is ready to copulate, she solicits to the male by giving a soft dee-dee-dee call. Pairs copulate frequently and the male mounts the female repeatedly.
The timing of the House Sparrow's breeding season is varied, depending mostly on the availability of insects.
The House Sparrow's nesting site is varied. It prefers the shelter of a hole, so its nests are most frequently built in the eaves and other crevices of houses. It also uses holes in in cliffs and banks, or in tree cavities. It sometimes excavates its own nests in sandy banks or rotten branches, but it more frequently uses the nests of other birds: swallows in banks and cliffs, and other birds that use old woodpecker cavities, such as bluebirds and the Eurasian Tree Sparrow. It usually uses old nests, though it sometimes usurps actively used nests. The House Sparrow nests more commonly in tree holes in North America than in Europe, and as such it is a factor in the decline of bluebirds and other North American cavity nesters. However, such behaviors are also observed in native North American species, such as the House Wren and the American Crow. The House Sparrow also builds its nests in the open, on the branches of trees, especially evergreens and hawthorns; or in the nests of larger birds such as storks or magpies. Such nesting sites are more common in warmer areas. Less common nesting sites used by the House Sparrow are streetlights and neon signs, favoured due to their warmth; and the old open-topped nests of other songbirds, which are domed over.
The nest is usually domed, though it sometimes is not roofed over when it is in an enclosed site. It has an outer layer of stems and roots, a middle layer of dead grass and leaves, and a lining of feathers, as well as paper and other soft materials.
The building of the nest is initiated by the unmated male, who begins construction while displaying to females. The female assists in building, but is less active than the male. Some nest building occurs throughout the year, especially after moult in autumn. In colder areas House Sparrows build specially created roost nests, or roost in streetlights, to avoid losing heat during the winter. The House Sparrow does not keep territories, but it defends its nest aggressively against intruders of the same sex.
Clutches usually contain four or five eggs, though clutches with only one egg or with up to six eggs have been recorded. Clutch size is larger at poleward latitudes and smaller near the sea and on islands. Central Asian House Sparrows, which migrate and have only one clutch a year, have an average of 6.53 eggs in a year. Variation in clutch size is caused by environmental and seasonal conditions, female age, breeding density, but is probably not hereditary. Some intraspecific brood parasitism occurs, and when several females dump their eggs in one nest it can contain ten eggs. The foreign eggs are sometimes recognised and ejected by females. Parasitism of other birds has been recorded once, when a House Sparrow accidentally dumped its eggs in the nest of a Cliff Swallow pair, which successfully raised the sparrow. The House Sparrow is itself parasitised by cuckoos, cowbirds, and other brood parasites, but only rarely, since it usually nests in holes to small for parasites to enter, and it feeds its young foods unsuitable for parasite chicks.
The eggs are white, bluish-white or greenish-white, spotted with brown or grey. Subelliptical in shape, they range from 20–22 millimetres (0.79–0.87 in) in length and 14–16 millimetres (0.55–0.63 in) in width, and have an average mass of 2.9 grams (0.10 oz), and an average surface area of 9.18 square centimetres (1.423 sq in). Eggs begin to develop with the deposition of yolk in the ovary a few days before ovulation. In the day between ovulation and laying, egg white forms, followed by eggshell. Eggs laid later in a clutch are larger, as are those laid by larger females, and egg size is hereditary. Eggs decrease slightly in size from laying to hatching. The yolk comprises 25 percent of the egg, the egg white 68 percent, and the shell 7 percent. Eggs are watery, being 79 percent liquid, and mostly protein otherwise.
The female develops a patch of bare skin, called a brood patch, and plays the main part in incubating the eggs. The male helps, but he can only cover the eggs rather than truly incubating them. The female spends the night incubating during this period, while the male roosts near the nest. Eggs hatch synchronously after 9–16 days.
A wide array of predators feed on the House Sparrow, with cats and birds of prey being predominant. In Europe and North America, nearly every species of bird of prey has been recorded preying on the House Sparrow. Accipiters and the Merlin in particular are major predators, though house cats likely make a greater impact on House Sparrow populations. Other predators include corvids, smaller squirrels, and even humans, as the House Sparrow has been consumed as food in many parts of the world, and still it is in parts of the Mediterranean.
The House Sparrow is host to a huge number of parasites and diseases. Ted R. Anderson listed hundreds, and noted that his list was incomplete. The effect of most of these is unknown. Many of the diseases hosted by the House Sparrow are also present in humans and their domestic animals, for which the House Sparrow acts as a reservoir host. Arboviruses such as the West Nile virus, which most commonly infect insects and mammals, survive winters in temperate areas by going dormant in birds such as the House Sparrow. The commonly recorded bacterial pathogens of the House Sparrow are often those common in humans, and they include Salmonella and Escherichia coli. Salmonella is common in the House Sparrow, and a comprehensive study of House Sparrow disease found it in 12.9 percent of sparrows tested. Salmonella epidemics in the spring and winter can be kill large numbers of sparrows. The House Sparrow hosts avian pox and avian malaria, which it has spread to the native forest birds of Hawaii. There are a few records of disease extirpating House Sparrow populations, especially from the Scottish islands, but this seems to be rare.
The House Sparrow is infested by a number of external parasites, which usually cause little harm to adult sparrows. The most common mite found on sparrows in Proctophyllodes, the most common ticks are Argas reflexus and Ixodes passericola. A number of chewing lice occupy different niches on the House Sparrow's body. Menacanthus lice are found across the House Sparrow's body, where they feed on blood and feathers, while Brueelia lice feed on feathers and Philopterus fringillae is found on the head. The most common flea on the House Sparrow is Ceratophyllus gallinae. The House Sparrow's nests are parasitised by a fauna of scavenging insects, including nest flies such as Neottiophilum praestum, and the species of Protocalliphora, and over 1,400 species of beetle.
The oldest known wild House Sparrow lived for nearly two decades; it was found dead 19 years and 9 months after it was ringed (banded) in Denmark. The oldest recorded captive sparrow lived for twenty-three years. In the adult House Sparrow, annual survival is between 45 and 65 percent. After fledgeing and leaving the care of its parents, the young House Sparrow has a high mortality rate, which lessens as it grows older and more experienced. Only about 20 to 25 percent of all sparrows hatched survive to their first breeding season.
The House Sparrow is considered to be a pest in much of its range, and with its extremely large range and population it is not believed to be threatened, so it is assessed as "Least Concern" on the IUCN Red List. It has been declining in many parts of the world. Even in North America and Australia, where the House Sparrow is considered an invasive species, declines have been noticed. In Eastern Europe, no serious declines have been reported. These declines were first noticed in the United States, where they were initially attributed to the spread of the House Finch, and have been most severe in Western Europe. In the Netherlands, the House Sparrow is even considered an endangered species, and the population of House Sparrows has dropped in half since the 1980s. In Britain populations peaked in the early 1970s, and have declined by 68 percent overall, and over 90 percent in urban areas. In London, the House Sparrow almost disappeared from the central city. These declines are not unprecedented, as such declines occurred when the internal combustion engine replaced the horse in the 1920s and the House Sparrow lost a major source of food in the form of spillage.
Various causes for its dramatic decrease in population have been proposed. Predation by accipiters, housecats, or corvids has commonly been proposed. Other proposed causes include electromagnetic radiation from mobile phones, disease, and lack of nesting sites because of a reduction in the number of badly maintained buildings. It seems, however, that the main cause of the House Sparrow's decline is a fall in insect numbers, as the House Sparrow requires insect food while in the nest. The main reason for these declines of insects seems to be changes in agricultural and gardening practices. Other causes for the fall in insect numbers may include the introduction of unleaded petrol, the combustion of which produces compounds such as methyl nitrite, a compound highly toxic for small insects; and reducing areas of free growing weeds.
The House Sparrow is closely associated with humans. Usually, it is regarded as a pest, since it consumes agricultural products and spreads disease to humans and their domestic animals. Even birdwatchers often hold it in little regard because of its molestation of other birds. Because of its familiarity, it is frequently represented in culture, representing the common and vulgar, or the lewd.
In most of the world, including the United States and Canada, the House Sparrow is not protected by law. In some it is protected, as in the Netherlands, where it is considered an endangered species.
Attempts to control House Sparrows include the trapping, poisoning, or shooting of adults; the destruction of their nests and eggs; or less directly, blocking nest holes and scaring off sparrows with noise, glue, or porcupine wire.