Pratincoles and Coursers (Glareolidae)

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Pratincoles and coursers

(Glareolidae)

Class Aves

Order Charadriiformes

Suborder Charadrii

Family Glareolidae

Thumbnail description
Small to medium-sized, rather slender, with long, pointed wings; bill short to moderately long, arched on culmen, sometimes colored red or yellow at base; legs long (coursers) or fairly short (most pratincoles); plumage usually quietly colored in brown, black, or white, except in Egyptian plover (Pluvianus aegyptius) which is boldly patterned in black, gray, and white

Size
6.7–11.4 in (17–29 cm); 1.3–6.1 oz (37–172 g)

Number of genera, species
6 genera; 16 species

Habitat
Desert, steppe, savanna, open woodland, and large rivers

Conservation status
Endangered: 1 species

Distribution
Africa, Eurasia, and Australia

Evolution and systematics

The oldest known fossil of the Glareolidae is Paractiornis from Lower Miocene deposits of North America, about 20 million years old. Fossils of the recent genus Glareola occur in the Middle Miocene of Europe, about 15 million years old. No fossil coursers have yet been found.

The coursers are structurally closer to other shorebirds. They are highly terrestrial and are probably ancestral to the pratincoles, which have diverged from the terrestrial condition to become specialized aerial feeders, often associated with large rivers. Coursers are more closely associated with arid habitats than are the pratincoles, again with the exception of the Australian pratincole (Stiltia isabella), which is mainly a bird of stony desert. The Egyptian plover is also exceptional in that it is a courser which inhabits the banks and sandbars of the larger rivers of Africa.

The closest relatives of the glareolids have long been a subject of discussion, but the latest evidence, based on DNADNA hybridization, suggests that they share a common ancestor with the aberrant crab plover (Dromas ardeola) and with the auks, gulls, and terns. These relationships are shown also by osteological and other evidence.

Physical characteristics

Glareolids have 15 cervical vertebrae; the middle toe is usually pectinate (but not in the Australian pratincole or in the Egyptian plover). The pratincoles are slender, swallow-like birds with long wings and relatively short legs, except in the long-legged Australian pratincole, which also has exceptionally long wings and courser-like plumage, indicating a transitional evolutionary stage between the pratincoles and the coursers. The hind toe of pratincoles is reduced and elevated; the front three toes are moderately long. The genus Glareola is characterized by a forked tail. Pratincoles have a wide gape to facilitate catching flying insects on the wing. The coursers are somewhat stockier than the pratincoles and have relatively shorter wings, a square tail, short front toes, and no hind toe. They have very long legs, except for the Egyptian plover whose legs are rather shorter and scaled in two rows back and front. The Egyptian plover may represent a family of its own, the Pluvianidae, or it may be separable merely as a subfamily Pluvianinae.

Distribution

The Egyptian plover occurs on the major rivers of tropical Africa, mainly north of the equator and south of the Sahara. Coursers occur throughout Africa, including the Sahara, as well as across the Arabian Peninsula into the Indian subcontinent. Pratincoles have a similar distribution to that of the coursers, but extend into southern Europe and Asia. One species is found in Madagascar and another in Australasia.

Habitat

Most pratincoles are associated with water in the form of large rivers or of inland pans. This is true even of the desert-dwelling Australian pratincole, which seldom nests more than a mile (1.6 km) from the nearest body of water. Some Eurasian pratincoles inhabit the region between short-grass steppes and desert, usually with surface water available in some form. The Egyptian plover is exceptional among coursers in that it occurs only on the larger tropical African rivers with sandbars. The remaining eight species of courser are all birds of dry habitats, from dry, thin forest to extreme desert.

Behavior

Pratincoles are almost invariably gregarious: flocks may number many hundreds of birds, especially in the nonbreeding season and during migration. The steppe-nesting species of the Northern Hemisphere migrate from their breeding grounds to Africa or Australia where they gather on grasslands and shorelines to rest and feed. The river-nesting pratincoles are largely nomadic, moving away from rivers when high water covers the rocks and sandbanks on which they normally nest and roost. Although silent much of the time, pratincoles may become quite vocal when migrating or when disturbed at their breeding sites, uttering loud, sharp tern-like calls. They roost on the ground or on rocks in midstream, usually in flocks, with all of the birds facing into the wind.

Coursers, as their name suggests, are great runners, hence their need for open ground. Most species prefer to run rather than to fly in the face of disturbance, but they fly extremely well when the need arises. Their plumage is usually highly cryptic, providing excellent camouflage, on which the birds rely for concealment. Coursers are seldom truly migratory, though some may have more or less seasonal movements. The species that inhabit the most arid environments are highly nomadic, moving about as the food supply dictates, or departing from regions where rainfall has brought on too dense a stand of vegetation. Most species are largely solitary, but members of the genus Cursorius often form flocks of 5–10 birds, seldom more.

Coursers are largely silent when on the ground, but have distinctive, loud flight calls. They also have sharp alarm calls when disturbed near the nest. They tend to be rather shy as a rule, seldom allowing a close approach, then running rapidly away before taking flight if hard pressed. They are active both day and night, becoming crepuscular or partly nocturnal in hot weather, especially on moonlit nights.

Feeding ecology and diet

All glareolids are largely insectivorous, although coursers may occasionally eat small mollusks and seeds. Pratincoles catch much of their food on the wing, but often chase insects on the ground also. The Australian pratincole is particularly adept at feeding both in the air and on the ground, since it has long wings as well as long legs. Coursers are exclusively ground feeders, taking their food by a run and a peck, much as plovers do. Members of the genus Cursorius use their relatively long, decurved bills for digging in soft soil to unearth insects or seeds.

Reproductive biology

All glareolids nest on the ground without any nest, or in a shallow scrape in the soil. The clutch consists of two to four eggs in those species of pratincoles that nest in the Northern Hemisphere; elsewhere the clutch seldom exceeds two eggs. The double-banded courser (Smutsornis africanus) invariably lays only one egg. Glareolid eggs are cryptically colored—a whitish or cream ground color is more or less heavily marked with black, brown, and gray streaks, spots, and blotches. Pratincoles usually nest in more or less dense colonies, but sometimes solitarily. Coursers are always solitary nesters. The three-banded courser (Rhinoptilus cinctus) lays its two eggs in a fairly deep scrape and incubates them partly buried in soil. The Egyptian plover also incubates its eggs partially buried in sand, and it will cover them completely when disturbed at the nest.

Conservation status

Only Jerdon's courser (Rhinoptilus bitorquatus) of eastcentral India is listed as endangered. No other glareolid is globally threatened. The rarity of Jerdon's courser is a result of habitat destruction and the bird's great sensitivity to human disturbance. At least two protected areas, the Sri Lanka-malleswara Wildlife Sanctuary and the Sri Venkateswara National Park, have recently (1992) been established for the bird's protection, and other protected areas are planned.

Significance to humans

In parts of Africa and southeast Asia, coursers and pratincoles are sometimes hunted for food, and the eggs of the collared pratincole (Glareola pratincola) used to be collected commercially for food, to the extent that some breeding colonies in Hungary were wiped out. These eggs are still collected in large numbers, mainly for the illegal egg-collecting trade. Furthermore, the practice of gathering chamomile on the grassy steppes of Hungary destroys many clutches of pratincole eggs. Otherwise glareolids impinge little on human activities beyond their aesthetic value to birdwatchers who seek them out as additions to their lists of desirable birds seen.

Species accounts

List of Species

Collared pratincole
Rock pratincole
Gray pratincole
Australian pratincole
Egyptian plover
Burchell's courser
Double-banded courser
Three-banded courser

Collared pratincole

Glareola pratincola

subfamily

Glareolinae

taxonomy

Hirundo pratincola Linnaeus, 1766, Austria. Three subspecies recognized.

other common names

English: Common pratincole, red-winged pratincole, locust bird, swallow-plover; French: Glaréole à collier; German: Rotflügel Brachschwalbe; Spanish: Canastera Común.

physical characteristics

8.7–9.8 in (22–25 cm); 2.1–3.7 oz (60–104 g). Slender, short-legged, long-winged; plumage mostly smoky grayish brown shading to white on belly. Throat yellowish buff surrounded by narrow black collar (absent when not breeding). Bill red at base and around gape. Underwing coverts dull rusty brown to chestnut.

distribution

The most widespread of the pratincoles. Breeding populations are scattered discontinuously throughout sub-Saharan Africa and Eurasia from Spain to Lake Balkhash in Kazakhstan. Nonbreeding birds migrate to sub-Saharan Africa.

habitat

István Sterbetz describes the habitat as the zone between short-grass steppes and desert, as well as floodplains, dried estuarine

mud banks, and marine shore with semi-desert features.

behavior

Collared pratincoles are highly gregarious at all times, even when breeding. They spend much time resting on the ground between bouts of aerial feeding. They tend to be vocal, especially in breeding colonies and on migration. Their flight is buoyant.

feeding ecology and diet

Catch flying insects on the wing and chase prey on the ground by running or by a short leap into the air. Food is mainly grasshoppers and beetles; during locust plagues, flocks of pratincoles devour large numbers of these insects.

reproductive biology

Breeds in spring in the Northern Hemisphere, in the dry season in most of tropical Africa and in early summer in southern Africa; breeding is usually in loose colonies. The nest is a shallow scrape, sometimes lined with a few bits of earth or dry plant fragments. The clutch in Eurasia is usually three eggs, but only two in Africa. The eggs are whitish to cream, heavily blotched with black, gray, and brown. Both sexes incubate for 17–19 days, and feed the precocial chicks for at least a week. The young fly at the age of about a month.

conservation status

Though not globally threatened, collared pratincoles have declined in numbers in Europe and parts of Africa as a result of pesticides, artificial fertilizers, habitat destruction, and disturbance, especially of breeding colonies. Breeding sites need protection.

significance to humans

Apart from the commercial collecting of eggs, the collared pratincole has little significance to humans. In the past it probably helped to control locust plagues, but the decline in numbers reduces the birds' impact in this regard.

Rock pratincole

Glareola nuchalis

subfamily

Glareolinae

taxonomy

Glareola nuchalis G. R. Gray, 1849, Fifth Cataract of the Nile, Sudan. Two distinctive subspecies.

other common names

English: Collared pratincole, white-collared pratincole, rufous- (or chestnut-) collared pratincole; French: Glaréole auréolée; German: Halsband-Brachschwalbe; Spanish: Canastera Sombría.

physical characteristics

7.1–7.5 in (18–19 cm); 1.5–2.0 oz (43–58 g). Small, charcoal gray, paler below, with white collar (subspecies nuchalis) or rufous collar (subspecies liberiae) on hindneck; legs and base of bill bright red.

distribution

Tropical Africa.

habitat

Larger rivers with exposed rocks and sand bars.

behavior

Usually in small flocks; perch on exposed rocks in midstream between bouts of aerial foraging. May also perch on riverside trees if rocks submerged. Migratory according to water levels, moving away from rivers that are flooded. Rather silent as a rule. May become tame around human habitations.

feeding ecology and diet

Forage both aerially and on rocks mostly at dawn and dusk, catching insects in flight or by running after them. May catch insects around street lights at night.

reproductive biology

Nest singly or in small colonies on exposed rocks, laying two eggs in a hollow or crevice of bare rock. Both sexes incubate for about 20 days and feed the chicks for a further 20–30 days when they reach flying age.

conservation status

Not threatened, but some stretches of river may be rendered unsuitable by damming and unseasonal release of water downstream. Rock pratincoles no longer occur in Sudan, where first collected, so numbers are probably declining.

significance to humans

None known.

Gray pratincole

Glareola cinerea

subfamily

Glareolinae

taxonomy

Glareola cinerea Fraser, 1843, mouth of River Niger, Nigeria. Monotypic.

other common names

English: Cream-colored pratincole; French: Glaréole grise; German: Graubrachschwalbe; Spanish: Canastera Gris.

physical characteristics

7.1–7.9 in (18–20 cm). Small and pale overall; above pale gray with rufous hindneck; below white, washed ochre across breast. Legs and base of bill red.

distribution

Tropical West Africa from Mali to Congo (Zaire).

habitat

Large rivers with exposed sand banks; in flood season also coastal habitats, including mangrove swamps.

behavior

Usually gregarious at all times. Forages on the wing and rests on sand banks.

feeding ecology and diet

Catches flying insects on the wing and also chases insects and spiders by running on ground.

reproductive biology

Nests colonially on sand banks, laying one or two eggs in an unlined scrape not far from water. Breeding biology poorly known.

conservation status

While still locally abundant, some breeding sites have been eliminated by damming, such as Lake Volta in Ghana. Also subject to human disturbance, but not under immediate threat.

significance to humans

None known.

Australian pratincole

Stiltia isabella

subfamily

Glareolinae

taxonomy

Glareola isabella Vieillot, 1816, Australasia. Monotypic.

other common names

English: Australian courser, long-legged pratincole, isabelline pratincole; French: Glaréole isabelle; German: Stelzenbrachschwalbe; Spanish: Canastera Patilarga.

physical characteristics

7.5–8.7 in (19–22 cm); about 2.3 oz (about 65 g). Slender and elegant with long legs and exceptionally long, pointed wings. Mostly light brown, paler on neck, with dark brown upper belly and white lower belly. Looks like a long-winged courser with a pratincole's head. Bill bright red at base. Rump white.

distribution

Breeds over much of inland and northern Australia. Nonbreeding birds migrate to extreme northern Australia, New Guinea, and eastern Indonesia.

habitat

Breeds in arid stony country or on short-grass plains, usually within a mile (1.6 km) or so of water; less often on shorelines of inland lakes and pans. Non-breeding birds occur on airfields, grassy plains, and fallow fields.

behavior

Usually gregarious, but sometimes solitary. Highly migratory in flocks that fly high with sweet, penetrating calls. Flight very light and tern-like. Runs swiftly on ground. Usually silent at breeding sites.

feeding ecology and diet

Catches insect prey by running pursuit on ground or in flight. On ground uses a wing to stop prey from escaping. May also feed on non-flying arthropods and some seeds. Drinks often, especially in hot weather.

reproductive biology

Nests solitarily or in small, loose groups on open shorelines and semi-desert plains, usually within a mile (1.6 km) of water. Two eggs are laid on bare soil, sometimes with a ring of small stones, droppings, or dry plant fragments around the site. Both parents incubate for about 20 days. Chicks are precocial, but are fed by parents for about a month. Between feedings, chicks hidden under shrubs or in shallow burrows. Young fly at about five weeks.

conservation status

Common to abundant throughout range; not threatened.

significance to humans

May be hunted for food in Indonesia.

Egyptian plover

Pluvianus aegyptius

subfamily

Cursoriinae

taxonomy

Pluvianus aegyptius Linnaeus, 1758, Egypt. Monotypic.

other common names

English: Crocodile bird, Egyptian courser; French: Pluvian fluviatile; German: Krokodilwächter; Spanish: Pluvial.

physical characteristics

7.5–8.3 in (19-21 cm); 2.6–3.2 oz (73–92 g). Small, plover-like, with gray back, buff underparts and boldly marked black and white head-and-neck pattern.

distribution

Tropical Africa from Senegal to Ethiopia, and south to Angola and Congo (Zaire).

habitat

Major lowland rivers with sand and gravel bars.

behavior

In pairs when breeding, but may form flocks of up to 60 birds when moving about according to changes in water level.

feeding ecology and diet

Feeds on invertebrates, mainly insects, caught by running after prey on ground or by a leap into the air; may also probe and scratch in damp sand for food.

reproductive biology

Breeds mostly in dry season when river levels low. Lays two to three eggs in deep scrape in sand, incubating eggs in partly buried position for 28–31 days. Eggs may be wetted with soaked belly plumage in hot weather. Chicks leave nest as soon as hatched, but may be buried in sand by parents when disturbed; parents may wet sand over chicks in the heat of the day. Young fly when about five weeks old.

conservation status

Common in suitable habitat, but some populations may be threatened by damming of rivers. No longer occurs in Egypt, where first described, so numbers may be dropping in parts of range.

significance to humans

None known.

Burchell's courser

Cursorius rufus

subfamily

Cursoriinae

taxonomy

Cursorius rufus Gould, 1837, Potchefstroom, South Africa. Monotypic.

other common names

French: Courvite de Burchell; German: Rostrennvogel; Spanish: Corredor Rufo.

physical characteristics

7.8–8.7 in (20–22 cm); 2.7–3.4 oz (76–95 g). More or less uniform brown, paler and more rufous below, shading to dark

brown bar on upper belly; lower belly white; eye-stripe black-and-white; hind-crown blue-gray. Legs long and white. Bill moderately long and decurved.

distribution

Southern Africa from Angola and Namibia to inland South Africa and southern Botswana.

habitat

Desert, semi-desert, open, short grassland.

behavior

Usually in pairs or small parties of up to 10 birds. Rather shy, running quickly away when disturbed. Takes flight when hard pressed.

feeding ecology and diet

Feeds mainly on insects caught by surface pecking or by digging with bill in soft soil or sand. Rarely takes seeds.

reproductive biology

Breeds at almost any time of year, laying two blackish eggs on bare ground, often among antelope droppings. Incubation and fledging periods not known. Chicks highly precocial, but are fed by parents for a few weeks after hatching.

conservation status

Formerly common over most of its range, Burchell's courser has undergone a significant decline in numbers. Reasons for this are not known, but the species is sensitive to disturbance and possibly to overgrazing of semi-desert habitat.

significance to humans

None known.

Double-banded courser

Smutsornis africanus

subfamily

Cursoriinae

taxonomy

Cursorius africanus Temminck, 1807, (Namaqualand), South Africa. Eight well-defined subspecies described, some geographically isolated.

other common names

English: Two-banded courser; French: Courvite á double collier; German: Doppelband-Rennvogel; Spanish: Corredor Escamoso Chico.

physical characteristics

7.9–9.4 in (20–24 cm); 2.0–3.7 oz (56–104 g). Small and graceful with long white legs and a short bill; mostly buff with heavily scaled dorsal plumage and lightly streaked blackish on neck; two bold black bands encircle the mantle and upper breast.

distribution

Discontinuously from South Africa to Somalia and Ethiopia.

habitat

Semi-desert with low shrubs, overgrazed grassland, and dry alkaline plains.

behavior

A typical courser, but more wary and better camouflaged than most species. Runs very fast when disturbed and in pursuit of prey. May stand behind shrub for concealment. Largely nocturnal in summer, otherwise active by day as well. Mostly solitary or in pairs.

feeding ecology and diet

Catches insects by pursuing them on the ground, but does not dig.

reproductive biology

Breeds throughout the year. Lays a single egg on bare ground, usually among antelope droppings or small stones. Both sexes incubate for 26–27 days. Chick leaves the nest site within 48 hours and is fed by the parents for several weeks. Young flies at about six weeks of age.

conservation status

The double-banded courser is common throughout most of its range and is not in need of special conservation measures.

significance to humans

None known.

Three-banded courser

Rhinoptilus cinctus

subfamily

Cursoriinae

taxonomy

Hemerodromus cinctus Heuglin, 1863, near Gondokoro, White Nile. Three subspecies.

other common names

English: Heuglin's courser, Seebohm's courser; French: Courvite á triple collier; German: Bindenrennvogel; Spanish: Corredor Escamoso Grande.

physical characteristics

9.8–11 in (25–28 cm); 4.2–5.3 oz (119–150 g). Two or three rather poorly defined subspecies are recognized.

distribution

Eastern Africa from extreme northern South Africa and Namibia to southern Sudan and Ethiopia.

habitat

Dry thorn scrub, bushy grassland, and sparse mopane woodland.

behavior

Usually singly or in pairs, less often in groups of up to six birds. Largely nocturnal. When disturbed may freeze before running swiftly away, then taking flight for a short distance. Roosts by day in shade of bush or tree.

feeding ecology and diet

Catches insects on the ground. Little else known.

reproductive biology

Nests mainly in dry season, making a deep scrape under a bush or tree. Clutch of two eggs partly buried in loose soil and incubated by both parents for about 25–27 days. Chicks are highly precocial, but the fledging period is unknown.

conservation status

The species is quite common over most of its range and is not threatened.

significance to humans

None known.

Resources

Books

Ali, Sálim, and S. Dillon Ripley. Handbook of the Birds of India and Pakistan. Vol. 3. Bombay: Oxford University Press, 1969.

Collar, N.J., et al. Birds to Watch 2: The World List of Threatened Birds. Cambridge, United Kingdom: BirdLife International, 1994.

Hockey, Phil. Waders of Southern Africa. Cape Town: Struik Winchester, 1995.

Maclean, G.L. "Family Glareolidae (Coursers and Pratincoles)." In Handbook of the Birds of the World. Vol. 3, edited by J. del Hoyo, A. Elliott, and J. Sargatal. Barcelona: Lynx Edicions, 1996.

Maclean, G.L., and M. Herremans. "Burchell's Courser." In The Atlas of Southern African Birds. Vol. 1, Non-passerines, edited by J.A. Harrison, et al. Johannesburg: BirdLife South Africa, 1997.

Maclean, G.L., and E.K. Urban. "Cursorius, coursers." In The Birds of Africa. Vol. 2, edited by Emil K. Urban, et al. London: Academic Press, 1986.

Pringle, John Douglas. The Shorebirds of Australia. North Ryde, Australia: Angus and Robertson, 1987.

Sibley, Charles G., and Jon E. Ahlquist. Phylogeny and Classification of Birds: A Study in Molecular Evolution. New Haven: Yale University Press, 1990.

Sterbetz, István. Die Brachschwalbe. Wittenberg Lutherstadt: A. Ziemsen Verlag, 1974.