Swallows

(Hirundinidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Hirundinidae

Thumbnail description
Small to medium-sized, slender, streamlined birds with pointed wings, a small bill, and perching feet; excellent fliers that catch their insect prey on the wing

Size
Body length ranges from about 3.9 to 9.4 in (10–24 cm); weight 0.4–2.1 oz (10–60 g)

Number of genera, species
15 genera; about 88 species

Habitat
Usually found in open habitats near water, along forested rivers, in wooded savanna, and near cliffs and caves close to open areas with an abundant supply of insects

Conservation status
Critically Endangered: 1 species; Vulnerable: 4 species

Distribution
Almost worldwide, with the exception of the high Arctic, Antarctica, and some remote oceanic islands.

Evolution and systematics

The evolutionary progenitor that gave rise to the modern swallow family probably separated from other primitive insectivorous birds in the Eocene (i.e., in the Lower Tertiary about 50 million years ago). In addition to many relatively recent adaptations related to their mode of aerial hunting, the swallows show some ancient evolutionary characters, such as the presence of bronchial rings, and so they are placed fairly low in the phylogenetic tree of the passerine birds (Passeriformes). Ornithologists consider the Hirundinidae to be closely related to larks (Alaudidae), pipits and wagtails (Motacilladae), and cuckoo-shrikes (Campephagidae).

The family Hirundinidae is separated into two major groups: the river-martins (subfamily Pseudochelidoninae) and the true swallows and martins (subfamily Hirundininae). The river-martins consist of only two species, while the true swallows include 14 genera and about 86 species. The river-martins have relatively robust legs and feet and a stouter bill than the other hirundines. They are thought to have diverged from the main hirundine line early in the evolution of the group.

During the past century, the classification of swallows and martins into genera has been modified several times. Initially, all the swallows (and also the swifts, now in the separate family, Apodidae) were placed into a single genus, Hirundo. With additional study, however, the swifts were recognized as being unrelated to the swallows and were assigned to their own family. More detailed research then resulted in the description of additional genera of swallows. Presently, 15 genera are recognized, with separation based on aspects of their morphology, biochemistry, and ecological and behavioral characters. Some genera form subgroups of closely related species.

Modern ornithologists do not consider the swallows (Hirundinidae) and swifts (Apodidae) to be closely related— their morphological and behavioral similarities are due to convergent evolution. Such convergence is manifest when, in otherwise not closely related organisms, similar body forms and behavioral traits develop as a result of selective pressures associated with comparable ecological niches. Their similar adaptations account for the fact that swallows and swifts are often confused and were once regarded as close relatives. Since the end of the nineteenth century, however, they have been recognized as belonging to different orders of birds— the swifts (Apodiformes) are not even perching birds.

Physical characteristics

Species in the swallow family are delicately built birds that can fly swiftly with great maneuverability and endurance. Their body length ranges from about 3.9–9.4 in (10–24 cm) and the weight from about 0.4–2.1 oz (10–60 g). The wings are long, pointed, and have nine primary feathers. The tail has 12 feathers and may be deeply forked, somewhat indented, or square-ended. The term "martin" often refers to species with a slightly indented or squared tail. The body plumage is short and pressed close to the skin. The most usual coloration is earth-brown or dark-and-white, often with

an attractive green or purple iridescence; rust-brown or rust-red markings are also frequent. The sexes do not differ in external appearance in most species. The flight muscles are strong, and the legs are short and permit only a clumsy waddling gait. The feet are typical of the perching birds. Swallows are primarily insect hunters, catching their prey almost exclusively in flight. To assist in this mode of feeding their small beak has a broad gape, with a wide base that runs almost as far back as the eye.

Distribution

Species of swallows occur almost worldwide, with the exception of the high Arctic tundra, Antarctica, and some isolated oceanic islands. Almost 30 species of swallows breed in Africa, and others migrate to winter there after breeding in Europe or Asia. Australia is home to four endemic species, while North America has nine species in six genera, and Central and South America have about 20 species. On a local scale, however, the distribution of swallows is usually rather patchy, depending on the presence of key habitat elements, particularly nesting sites.

Habitat

Major habitats for swallows and martins include forested ecosystems close to lakes, rivers, streams, and wetlands, as well as wooded savanna and prairies. Their habitats are normally open areas with an abundant supply of flying insects as prey. The proximity of appropriate nest-site habitat is also critical. Some swallow species utilize tree cavities for nesting, while others require mud or sand banks in which nesting tunnels can be dug, and yet others demand access to soft mud as a material used to construct clinging nests on cliffs or other vertical structures. Swallows and martins have fewer habitat restrictions during the non-breeding season, and they may migrate or wander extensively at that time.

Specific habitat requirements differ greatly among genera in the swallow family. Species in the genus Hirundo, for example, have specialized habitat needs ranging from desert to tropical rainforest, and from highlands to seacoasts. Some swallow species have greatly expanded their range of habitat utilization by taking advantage of human-built structures for nesting. For instance, barn swallows (Hirundo rustica) commonly nest on or inside of farm buildings and cottages, whereas they were previously restricted to using caves and cliffs in coastal areas. This adaptive change to utilizing anthropogenic habitats has allowed barn swallows to expand their range and overall abundance. Similarly, cliff swallows (H. pyrrhonota) often build their nests in protected locations on bridges and buildings. Most species of hirundines, however, continue to use only natural nesting sites.

Behavior

Swallows are excellent fliers, and are capable of executing impressive aerial maneuvers when hunting or courting. Males typically choose and defend a nest site and then attract a female and guard their territory using song and inspiring flight patterns. The size of the defended territory may be quite small in colonial-nesting species, being restricted to the nest-site itself and a small surrounding area. It may, however, be considerably larger for species that do not nest in groups. Mated pairs of non-migratory species often stay in the vicinity of their breeding area all year, although they defend the nest site most vigorously during the breeding season. Migratory species often return to the same breeding area each year, and may even utilize the exact same nest site if they have been successful there previously. First-year breeders typically return to a breeding area close to where they were born and raised.

Behavioral displays have not been well studied for many species of swallows and martins, but they appear to be important in attracting a mate and defending the nest-site and breeding territory. Aggressive displays can include ruffling of the head and neck feathers, quivering of the wings, bill snapping,

and lunging at an opponent. Swallows may also gape aggressively with their bill open and neck extended when other birds approach their nest site. Displays associated with pairing and copulation often include the male flying skillfully, quivering of the wings, and spreading of the tail. Females may also quiver their wings prior to mating. Plumage appears to play a key role in such displays—during singing or threat displays males often show prominent colored patches on their forehead and throat. The tail of some swallows, when spread, shows additional markings.

Swallows exhibit an array of calls, which are used when excited or agitated, to maintain contact with others of the same species, during courtship, or as an alarm indicating the presence of a predator. In addition, begging calls are used by the young when soliciting food from their parents. The typical song of swallows is a simple, sometimes musical twittering.

Feeding ecology and diet

Swallows feed almost exclusively on insects that they catch in flight. The tree swallow (Tachycineta bicolor) is the only species that eats a substantial amount of plant food, including berries and other small fruits. Specific information is lacking on the diet of many swallow species, and the size of insects consumed varies greatly. The largest species are able to catch and eat dragonflies and butterflies, but the majority of swallows consume medium-sized insects such as flies, beetles, and ants. They tend to avoid stinging insects such as bees and wasps. Swallows also will sometimes eat spiders. Their diet typically changes during the year depending on which insect species are available.

Swallows usually feed in areas where insects are plentiful and often catch their prey when flying in open places. Consequently, swallows are often seen flying above areas of open habitat, such as over water or near a forest edge or above the canopy. During the breeding season, they typically feed rather close to the nesting site. During inclement weather, however, they may need to fly more than a kilometer to find suitable food. Swallows may feed in large groups or flocks, or they may hunt individually.

Reproductive biology

Hirundines form monogamous breeding pairs, but males are often promiscuous and will attempt to copulate with females other than their mate. This typically happens at locations where the birds congregate in flocks. In some species, the males closely guard their mate, although this is not always the case, as in the colonial cliff swallow in which guarding the nest site is more important than defending the mate.

Nest construction is highly variable among species of swallows and martins. Their nests are usually built of mud used to cement grasses and twigs, and are typically located in a tree cavity, in a tunnel dug in an earthen or sandy bank, on a rocky cliff, or on a wall or in an accessible building. Hole nesters may use pre-existing cavities such as a hollow

tree, an abandoned woodpecker hole, or a crevice in a cliff or rocky slope. Other species dig a 3.3–6.6 ft (1–2 m) long burrow in the side of a riverbank or sandy slope. Nests made of mud are typically attached to a protected portion of a cliff, cave, or tree, or they may be attached to an artificial structure such as a bridge or a building wall beneath an overhang. The mud nest may be an open bowl, such as the barn swallow constructs, or an enclosed mud nest, such as the cliff swallow creates. Mud nests may be renovated and used several years in a row.

Hirundines that nest in cavities typically have white eggs, while those with open nests have eggs that are spotted and/or lightly colored. Clutch size is commonly four or five eggs, but can range from about two to eight. Clutches are typically smaller in the tropics at two or three eggs, and larger in temperate areas, as many as seven or eight eggs. The average clutch size tends to decrease for second and later clutches in re-nests during the same breeding season. Eggs are laid a day apart and the incubation period ranges from 11 to 20 days, with 14–16 days being typical. Incubation is by the female only in some species, and by both parents in others.

Eggs within a clutch hatch asynchronously over several days. Because the nestlings initially have little down, they need to be brooded by one of the parents until they become better feathered. The parents alternate the brooding chore. The parents feed the young as frequently as possible, often several times an hour. After the nestlings become sufficiently feathered to regulate their own body temperature, both parents are able to search for food at the same time. Nestling survivorship is strongly tied to weather conditions, which affects the availability of insect prey. Many nestlings may die of starvation during prolonged bad weather. Ectoparasites and predation can also be important causes of nestling mortality. The nestling period is approximately three weeks, ranging from 17 to 30 days. After they fledge, juveniles will still be fed by their parents for several weeks, until they become self-sufficient.

Conservation status

Five species of hirundines are at risk. The white-eyed river martin (Eurychelidon sirintarae) of Thailand is listed as Critically Endangered, although it has not been seen for more than 20 years and may already be Extinct. Four other species are listed as Vulnerable. They are the blue swallow (Hirundo atrocaerulea) of tropical and southern Africa, the white-tailed swallow (H. megaensis) of Ethiopia, the Bahama swallow (Tachycineta cyaneoviridis) of the Bahamas, Cuba, and the extreme southeastern United States, and the golden swallow (T. euchrysea) of the Dominican Republic, Haiti, and Jamaica. Four additional species are listed as Data Deficient, meaning they are likely at risk but additional research is required to conclusively demonstrate this. These additional species are the Red Sea cliff-swallow (Hirundo perdita) of Sudan, Brazza's swallow (Phedina brazzae) of Angola, Congo, and the Democratic Republic of Congo, the Sinaloa martin (Progne sinaloae) of Guatemala and Mexico, and the African river-martin (Pseudochelidon eurystomina) of Congo, the Democratic Republic of Congo, and Gabon.

However, current research and monitoring of the distribution and abundance of rare swallow species is incomplete. Local climate changes can cause local population declines, and competition for nest sites from abundant non-native cavity nesters, such as house sparrows (Passer domesticus) and starlings (Sturnus vulgaris), has caused local declines in swallow and martin populations. Pollution and insecticides are also suspected to have caused declines in swallow populations due to reductions of insect populations, contamination of mud used to build nests, and direct poisoning of birds. Habitat destruction also is a concern for all threatened swallows.

Significance to humans

Typically, there is little direct interaction between humans and swallows. Sometimes, their nests on buildings are viewed as a nuisance and are removed by people. Only the African river-martin is hunted as a minor source of food. Humans may, however, have large indirect influences on swallow populations through the destruction of their habitat and the creation of toxic pollution. On the other hand, some species of swallows benefit from the presence of bridges, sheltered places beneath building overhangs, and other built structures that are used as nesting habitat. Some species are also aided by the provision of nesting boxes for their use. There are also indirect economic benefits of ecotourism and bird-watching focused on seeing swallows and other native birds in natural habitats. Species of swallows that live in residential and urbanized areas are often greatly appreciated by local people, and may even be considered harbingers of good fortune.

Species accounts

List of Species

African river-martin

Pseudochelidon eurystomina

subfamily

Pseudochelidoninae

taxonomy

Pseudochelidon eurystomina Hartlaub, 1861, Gabon.

other common names

English: Congo swallow; French: Hirondelle de rivière; German: Trugschwalbe; Spanish: Avión de Río Africano.

physical characteristics

5.5 in (14 cm). The plumage is glossy black overall and the beak, feet, and eyes are colored red.

distribution

Breeds in coastal Gabon and inland along the Congo River and other large tropical rivers of central western Africa. After breeding it migrates far up the Congo River and other major watercourses in the region. It occurs in Congo, the Democratic Republic of Congo, and Gabon.

habitat

Breeds in sandy places along forested tropical rivers and in coastal tropical savanna. After breeding it migrates inland along large forested rivers, where it often roosts on sandy bars and embankments.

behavior

The species is highly gregarious when breeding and also during migration. It defends a local territory around the nesting site, and attracts a mate by aerial displays and singing.

feeding ecology and diet

Feeds on flying insects caught on the wing.

reproductive biology

Monogamous. Populations breeding on large rivers breed during the drier season, when sandy riverbanks are exposed. Populations breeding in coastal savanna breed from about September to November. Colonial nesting sites are in sandy embankments, dunes, and islands of large tropical rivers and coastal savanna. It digs a slanting tunnel of 6.6–10 ft (2–3 m) into soft ground for its nesting site. The clutch size is two to four eggs. Both parents share in the incubation and care of the young.

conservation status

A rare, little-known, but locally abundant species that is listed as Data Deficient.

significance to humans

African river-martins have been recently hunted in significant numbers by local people as a source of food. Otherwise, they are of no direct importance to humans, except for indirect economic benefits of ecotourism involving rare birds.

Barn swallow

Hirundo rustica

subfamily

Hirundinae

taxonomy

Hirundo rustica Linnaeus, 1758. Six subspecies are recognized.

other common names

English: Chimney swallow, European swallow, house swallow, swallow; French: Hirondelle de cheminée; German: Rauchschwalbe; Spanish: Golondrina Bermeja.

physical characteristics

7.5 in (19 cm); 0.6 oz (17 g). The back is glossy blue-black, the throat and belly rusty brown, and there is a brighter rusty-red patch on the forehead. The tail is deeply forked. The six geographic subspecies vary somewhat in coloration.

distribution

The most widespread species of swallow. It breeds in northern regions of Eurasia, North America, and northern North Africa. It migrates to winter in more southern regions of its range, including northern and central South America, central and southern Africa, and South and Southeast Asia.

habitat

Forages in open areas, often close to water. Nests primarily on built structures, as well as natural cliffs and caves.

behavior

Begins to migrates south at the end of August, but particularly in the first half of September. Before they depart and while resting during migration, they may aggregate into large flocks, often with other species of swallows. Late migrants may persist until late October or early November. Has a loud, twittering song and is perhaps the most talented singer in the family. Its contact call, used to attract and connect with others, is a high-pitched, loud, repeated weet.

feeding ecology and diet

Feeds on insects caught in flight.

reproductive biology

Monogamous. Builds a cup-shaped nest of mud and some plant fibers, often attached to a building beneath a shading overhang, and sometimes inside if there is easy access. Its natural nest sites are cliffs, cave walls, and clefts in the ground. It usually takes about eight days to build a new nest, but in unfavorable weather this may be as long as four weeks. The nest is lined mostly with feathers. A nest may be used for a decade or longer, being refurbished each year. The clutch is typically three to six eggs. However, clutches laid later in the season have fewer eggs. Generally only the female incubates, although the male may also participate, especially in the American subspecies. The young hatch asynchronously after 11–18 days of incubation and are fledged after 15–23 days. Generally breeds once or twice per season, rarely three times.

conservation status

Not threatened. A widespread and abundant species.

significance to humans

The barn swallow is a popular bird for many people. In parts of Europe it is considered an omen of good luck and a harbinger of spring. It has lived for millennia in close association with humans, and has likely benefited from this relationship and become more abundant than in former times. This bird is welcomed by farmers because it eats many insect pests that affect livestock and crops.

American cliff swallow

Hirundo pyrrhonota

subfamily

Hirundinae

taxonomy

Hirundo pyrrhonota Vieillot, 1817.

other common names

English: Cliff swallow; French: Hirondelle à front blanc; German: Fahlstirnschwalbe; Spanish: Golondrina de las Rocas.

physical characteristics

5.1 in (13 cm); 0.8 oz (22.7 g). It has a bluish brown back, tail, and wings, a reddish rump, blue on the crown of the head, a rusty-brown chin and sides of head, and a white forehead.

distribution

Breeds locally but widely in North America and migrates to winter in Central America and northern South America.

habitat

Occurs in open areas near suitable breeding sites, often near water.

behavior

A migratory species that spends the non-breeding season in southern parts of its range. During migration it gathers in large flocks. The song is a simple, melodious note.

feeding ecology and diet

Feeds on flying insects caught on the wing.

reproductive biology

Monogamous. Builds a bulb-shaped nest of clay beneath a sheltering projection on a cliff. They may also nest beneath overhanging eaves of a building, within the structure of a bridge, or on protected places on a dam. A social species that nests in colonies of various size. The clutch size is usually three to four eggs. The eggs are incubated by the female, but both parents feed the young.

conservation status

Not threatened. A widespread and locally abundant species.

significance to humans

A familiar and popular bird to many people.

House swallow

Hirundo tahitica

subfamily

Hirundinae

taxonomy

Hirundo tahitica Gmelin, 1789.

other common names

English: Hill swallow, Pacific sea swallow, Pacific swallow, welcome swallow; French: Hirondelle de Tahiti; German: Südseeschwalbe; Spanish: Golondrina Pacífica.

physical characteristics

5.1 in (13 cm). The back, wings, and tail are colored glossy purple-black, with a reddish face and chin and a brown-streaked belly. The tail is deeply forked.

distribution

Southern India, Southeast Asia, New Guinea, and many Pacific islands.

habitat

Occurs in open tropical habitats, usually in the vicinity of coastal water.

behavior

A non-migratory species that uses song and aerial display to defend a breeding site and attract a mate. The song is a loud twittering.

feeding ecology and diet

Feeds on insects that are caught in flight.

reproductive biology

Monogamous. Builds a cup-shaped nest of mud and some plant fibers that is attached to a cliff or building. The clutch size ranges from one to three eggs. The eggs are incubated by the female, but both parents feed the young.

conservation status

Not threatened. A widespread and locally abundant species.

significance to humans

Not of much importance to humans, other than the indirect economic benefits of ecotourism focused on birding.

House martin

Delichon urbica

subfamily

Hirundinae

taxonomy

Hirundo urbica Linnaeus, 1758. Six geographic subspecies are recognized.

other common names

English: Common house-martin, northern house-martin; French: Hirondelle de fenêtre; German: Mehlschwalbe; Spanish: Avión Común.

physical characteristics

5.5 in (14 cm). It is colored glossy purple-brownish on the back and white below, with a white rump and a forked tail.

distribution

Breeds widely in Eurasia, from Britain through to Japan and the Koreas, and including part of northern North Africa. It

migrates to spend the non-breeding season in central and southern Africa, South Asia, and southeastern China.

habitat

Occurs in open areas, usually close to water, and also in towns and residential areas.

behavior

It migrates to spend the non-breeding season in southern parts of its range. Attracts a mate and defends a nest site by song and aerial displays.

feeding ecology and diet

Feeds on flying insects, which are caught on the wing.

reproductive biology

Monogamous. The nest is a half-cup of mud with an oval entrance at the top and is built against a vertical wall under an overhanging roof. It is usually placed on a building in an open area, but the species also breeds on natural cliff faces. Both sexes incubate the four to five eggs and there are often two broods per season.

conservation status

Not threatened. A widespread and abundant species.

significance to humans

The house martin is a popular bird for many people. It lives in close association with humans and has likely benefited from this relationship and become more abundant than in former times.

Mascarene martin

Phedina borbonica

subfamily

Hirundinae

taxonomy

Hirundo borbonica Gmelin, 1860.

other common names

English: Mascarene swallow; French: Hirondelle des Mascareignes; German: Maskarenenschwalbe; Spanish: Golondrina de Mascarene.

physical characteristics

Colored brownish overall, with a whitish rump and white throat. Has long pointed wings and a slightly forked tail.

distribution

An endemic species that only breeds on the islands of Madagascar, Mauritius, and Reunion, all in the western Indian Ocean off eastern Africa. Migrants from Madagascar may occur in southern and eastern Africa during the non-breeding season.

habitat

Occurs in open areas, usually near water.

behavior

It is generally a resident species, but birds from Madagascar may wander during the non-breeding season and can occur in continental Africa. Attracts a mate and defends a nest site by song and aerial displays.

feeding ecology and diet

Feeds on insects, which are caught in flight.

reproductive biology

Monogamous. Builds a simple cup-shaped nest of twigs on a rocky cliff and sometimes on buildings. The clutch size is two to three eggs, and both parents feed the young.

conservation status

Not threatened. An endemic species but locally abundant within its restricted range. Its populations are vulnerable to devastatation by monsoons.

significance to humans

Of no direct importance to humans, except for indirect economic benefits of ecotourism involving rare birds.

Sand martin

Riparia riparia

subfamily

Hirundinae

taxonomy

Hirundo riparia Linnaeus, 1758.

other common names

English: Bank swallow; French: Hirondelle de rivage; German: Uferschwalbe; Spanish: Avión Zapador.

physical characteristics

5 in (12 cm); 0.5 oz (14 g). The back and wings are colored brownish, with a white chin and belly and a brown band across the chest.

distribution

Breeds widely throughout most of Eurasia and North America. It migrates to spend the non-breeding season in southern parts

of its range, including central and northern South America and south and Southeast Asia.

habitat

Often occurs in the vicinity of high sandy banks and cliffs near water, but may also breed away from water in old sand quarries.

behavior

A migratory species that winters in southern parts of its range. Attracts a mate and defends a nest site by song and aerial maneuvers. The most common call is a hoarse, whetstone-like sound.

feeding ecology and diet

Feeds on flying insects that are caught on the wing.

reproductive biology

Monogamous. Builds a nest at the end of an approximately 3-ft (1-m) long passage dug into an earthen or sandy bank. The clutch consists of three to six white eggs. There are from one to three broods per season, depending on the local food availability.

conservation status

Not threatened. A widespread and abundant species.

significance to humans

A familiar and popular bird to many people.

Purple martin

Progne subis

subfamily

Hirundinae

taxonomy

Hirundo subis Linnaeus, 1758.

other common names

French: Hirondelle noire; German: Purpurschwalbe; Spanish: Golondrina de Iglesias.

physical characteristics

7 in (18 cm); 1.7 oz (48 g). The male is colored overall a glossy, iridescent purple-black, with darker wings, while the female is brownish with a lighter belly.

distribution

Breeds widely in North America, from southern Canada to northern Mexico. It migrates to spend the non-breeding season in central South America.

habitat

Inhabits open areas near suitable nesting sites, often near water.

behavior

A long distance migrant, it winters in southern parts of its range (Venezuela to southeastern Brazil). During migration it often gathers in large flocks. Attracts a mate and defends a nest site by song and aerial maneuvers. The song is a low-pitched, bubbling twitter.

feeding ecology and diet

Feeds on insects that are caught in flight.

reproductive biology

Monogamous. Breeds in colonies in special, apartment-style nest-boxes with individual compartments, or in a dead, hollow tree. It may be non-colonial at natural nesting sites. Typically lays a clutch of four to six eggs. The eggs are incubated by the female, but both parents feed the young.

conservation status

Not threatened. A locally abundant species, although declining over parts of its range. The practice of removing dead trees with cavities has reduced nesting sites, and introduced species also compete for nesting cavities.

significance to humans

A familiar and popular bird to many people. An occupied apartment nest-box is highly prized, because of the lively nature of the martins and the fact that they eat such large numbers of irritating insects, such as mosquitoes.

Crag martin

Ptyonoprogne rupestris

subfamily

Hirundinae

taxonomy

Hirundo rupestris Scopoli, 1769.

other common names

English: Eurasian crag martin; French: Hirondelle de rochers; German: Felsenschwalbe; Soanish: Avión Roquero.

physical characteristics

5 in (14 cm). It has a brownish gray back, tail, and wings, a lighter colored throat and belly, and white spots on the tail.

distribution

Occurs in mountainous regions of southern and central Europe, western and central Asia, and northern North Africa. It migrates to winter in southern parts of its range in the Middle East and central and southern Africa.

habitat

A migratory species that inhabits open meadow habitat near cliffs and ravines, often near water, in mountainous areas at mid-elevation.

behavior

Usually migrates in flocks. It defends a breeding site and attracts a mate by song and aerial displays.

feeding ecology and diet

Feeds on insects that are caught in flight.

reproductive biology

Monogamous. The nest is built of mud and is typically located beneath a protecting overhang on a rocky cliff. Typically lays a clutch of three to four eggs, which are incubated by the female. Both parents feed the young.

conservation status

Not threatened. A widespread and locally abundant species.

significance to humans

Not of much importance to humans, but sought after by birders and other ecotourists.

Square-tailed saw-wing

Psalidoprocne nitens

subfamily

Hirundinae

taxonomy

Atticora nitens Cassin, 1857.

other common names

English: Square-tailed saw-winged swallow; French: Hirondelle à queue courte; German: Glanzschwalbe; Spanish: Alas de Sierra de Cola Cuadrada.

physical characteristics

4 in (11 cm). The body is overall colored glossy dark-brown and black, with sheens of green and purplish and a squared back of the tail. Males have a distinctive, hook-like thickening of the outer vane of the first primary, which may play a role in mating or a means of clinging to a vertical wall.

distribution

Central and western tropical Africa.

habitat

Occurs in open areas within tropical forested habitats, generally near water.

behavior

A non-migratory species that uses aerial display and a relatively faint song to defend a breeding site and attract a mate.

feeding ecology and diet

Feeds on flying insects, which are caught on the wing.

reproductive biology

Monogamous. Nests in a tunnel dug into a sandy bank. The clutch size is two eggs.

conservation status

Not threatened. A locally abundant species.

significance to humans

Not of much importance to humans, other than the indirect economic benefits of ecotourism focused on birding.

Resources

Books

Ali, Salim, and S. Dillon Ripley. Handbook of the Birds of India and Pakistan. 2nd ed. New York: Oxford University Press, 1981.

BirdLife International. Threatened Birds of the World. Barcelona, Spain and Cambridge, UK: Lynx Edicions and BirdLife International, 2000.

Brown, C., and M. Brown. Coloniality in the Cliff Swallow. Chicago: University of Chicago Press, 1996.

Cramp, Stanley, K.E.L. Simmons, and C.M. Perrins, eds. Birds of the Western Palearctic. Vol. 5, Tyrant Flycatchers to Thrushes. Oxford, UK: Oxford University Press, 1988.

Howell, S.N.G., and S. Webb. A Guide to the Birds of Mexico and Northern South America. Oxford, UK: Oxford University Press, 1995.

Keith, Stuart, et al. The Birds of Africa. Vol. 4. New York: Academic Press, 1992.

Meyer de Schauensee, R.A., and W.H. Phelps, Jr. A Guide to the Birds of Venezuela. Princeton, NJ: Princeton University Press, 1978.

Ridgely, R.S., and G. Tudor. The Birds of South America. Austin: University of Texas Press, 1989.

Sibley, D. The Sibley Guide to Bird Life and Behavior. New York: Alfred A. Knopf, 2001.

Turner, A., and C. Rose. Swallows & Martins: An Identification Guide and Handbook. Boston: Houghton Mifflin Company, 1989.

Periodicals

Bent, A.C. "Life Histories of North American Flycatchers, Larks, Swallows, and Their Allies." U.S. National Museum Bulletin 179 (1942).

Organizations

BirdLife International. Wellbrook Court, Girton Road, Cambridge, Cambridgeshire CB3 0NA United Kingdom. Phone: +44 1 223 277 318. Fax: +44-1-223-277-200. E-mail: [email protected] Web site: <http://www.birdlife.net>

IUCN–The World Conservation Union. Rue Mauverney 28, Gland, 1196 Switzerland. Phone: +41-22-999-0001. Fax: +41-22-999-0025. E-mail: [email protected] Web site: <http://www.iucn.org>

Gregory J. Davis, PhD

Bill Freedman, PhD