Pterocliformes (Sandgrouse)

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Pterocliformes

Sandgrouse

(Pteroclididae)

Class Aves

Order Pterocliformes

Family Pteroclidae

Number of families: 1


Thumbnail description
Medium-sized, pigeon-like birds, with a stocky body, small head, short bill and legs, and camouflaged plumage

Size
9.8–19 in (25–48 cm); 0.7–1.2 lb (130–550 g)

Number of genera, species
2 genera; 16 species

Habitat
Desert, semi-desert, open steppe, and dry savanna, always within flying range of drinking water

Conservation status
Not threatened

Distribution
Africa, Madagascar, Iberian and Arabian peninsulas, Middle East to Indian subcontinent, China, and Mongolia

Evolution and systematics

Sandgrouse are known as fossils of the genus Archaeoganga from the Upper Eocene of France, some 35 million years ago, one species of which is estimated to have been about three times the size of the largest living sandgrouse species, weighing perhaps 3 lb (nearly 1.5 kg). Other fossil genera occur into the Lower Miocene, about 20 million years ago. The general consensus, based on morphological, behavioral, and chromosomal evidence, is that sandgrouse are derived from the shorebirds (order Charadriiformes) and are sometimes grouped in that order under the suborder Pterocli. However, even the earliest fossil sandgrouse show marked divergence from the ancestral shorebird. They are no longer regarded as closely related to doves and pigeons (order Columbiformes), with which they were placed for many years.

Sandgrouse probably evolved in the arid zone of North Africa and the Middle East, spreading to southern Africa and central Asia. They are more closely associated with the Afro-Asian deserts than any other family of birds. The 14 species of the genus Pterocles retain a rudimentary hind toe; this toe has been lost in the two species of Syrrhaptes that are likely to be more recent offshoots of the ancestral sandgrouse stock. Four species of sandgrouse (Lichtenstein's, double-banded, four-banded, and painted) share the habit of crepuscular or nocturnal drinking and may constitute a separate genus (or at least a subgenus) Nyctiperdix on the basis of this and the possession of a strongly barred abdomen in both sexes.

Physical characteristics

Sandgrouse are stocky terrestrial birds with dense, beautifully camouflaged plumage. They are covered with an underdown even between the main feather tracts. Their lower legs are feathered in front in the genus Pterocles, whereas the whole lower leg and the toes are feathered in Syrrhaptes, possibly as an adaptation to cold climates. Despite their short legs, sandgrouse walk and run well. The nostrils of all species are covered with fine feathers. Their wings are long and pointed, giving them exceptional powers of flight. The sexes differ markedly in plumage pattern, the females being more cryptically colored than the males.

Distribution

Sandgrouse occur from South Africa and Namibia through the drier parts of East Africa to North Africa, Spain, the Arabian peninsula, central Asia, Mongolia, and India.

Habitat

Desert, semi-desert, dry savanna, and short-grass steppe.

Behavior

Sandgrouse are the most terrestrial of birds, feeding, roosting, and nesting on the ground. They fly to water almost every day, covering up to about 75 mi (120 km) round-trip,

depending on the location of feeding areas. All species are gregarious, except when breeding: flocks may number hundreds or thousands of birds. They call to each other in flight and sometimes when flocking on the ground. Adaptations of sandgrouse to arid zones include: seeking shade in hot conditions, flying and feeding in the cooler hours of the day, insulation against overheating by dense plumage, and huddling together under extreme conditions. Some species of sandgrouse also may limit their frequency of drinking to conserve energy, though this may not be possible in hot conditions.

Feeding ecology and diet

Sandgrouse feed almost exclusively on small seeds picked up from the surface of the soil; the birds also use their bills to flick loose sand sideways to uncover buried seed. Because of the dry diet, they must drink often, especially in hot weather when drinking may occur daily. Most species drink an hour or two after sunrise, but some drink only at dusk or at night. Sandgrouse drink by dipping the bill, sucking a draft of water, and raising the head to swallow, taking several drafts at each bout of drinking.

Reproductive biology

Sandgrouse are monogamous, solitary nesters, though nests may be fairly close together, giving the appearance of a loose colony. The nest is a shallow scrape, often under a plant, but also in the open; it is usually lined with fragments of soil, stone, or plants. Clutches usually contain three rather elongated, spotted eggs. Each clutch is incubated by the female during the day and by the male at night, at least in those species which have been studied. The chicks hatch after about 21–31 days, depending on the species. They feed themselves but are given water by the male parent, which soaks his belly

feathers at a drinking place and flies back to the chicks, which take the water from his plumage. This method of providing the chicks with water is unique among birds. Sandgrouse young fly at about four to five weeks, after which they accompany their parents on flights to the watering hole.

Conservation status

Sandgrouse are abundant throughout their distribution and are not in need of special conservation measures. However, where they are hunted for sport, the shooting season needs to be regulated to avoid overexploitation.

Significance to humans

In many parts of their range, sandgrouse are considered good eating and are hunted at watering points. Because most species inhabit remote areas, they generally suffer little human disturbance away from their drinking places.

Species accounts

List of Species

Namaqua sandgrouse
Spotted sandgrouse
Chestnut-bellied sandgrouse
Black-bellied sandgrouse
Lichtenstein's sandgrouse
Pallas's sandgrouse

Namaqua sandgrouse

Pterocles namaqua

taxonomy

Tetrao namaqua Gmelin, 1789, Namaqualand, South Africa. Monotypic.

other common names

French: Ganga Namaqua, ganga de Namaland; German: Namaflughuhn; Spanish: Ganga Namaqua.

physical characteristics

9.4–11 in (24–28 cm); 5–8.5 oz (143–240 g). Medium-sized; tail wedge-shaped; central, elongated tail feathers. Male has yellowish olive head, breast and mantle; double breast-band white, bordered below with maroon; belly and back brown; back spotted pearl-gray. Female mostly barred brown and buff; streaked brown and buff on head and neck.

distribution

Southern Africa from extreme southwestern Angola through Namibia to Botswana and western South Africa.

habitat

Open desert and semi-desert, usually stony with low shrubs; sandy desert with scattered grass tufts.

behavior

Gregarious, except when nesting. Flocks may number several hundred or thousands of birds at watering points. Usually drinks in the morning up to three hours after sunrise; some birds may drink only every three to five days. Feeding grounds

may be 35 mi (60 km) from nearest palatable drinking water. Flies up to 45 mi (70 km) per hour; birds in flock keep contact with an intermittent, three-note call.

feeding ecology and diet

Feeds mainly on small, dry seeds picked up from surface of soil. Drinking water needed to augment lack of water in food and for evaporative cooling in hot weather.

reproductive biology

Nests solitarily on open ground, which is usually stony and shrubby. Nest is shallow scrape lined with some pebbles and bits of dry vegetation. Clutch of three well camouflaged eggs incubated by female during day and by male at night for about three weeks. Chicks leave nest within 24 hours of hatching; can fly at about a month. Chicks dependent on male parent for water for two to three weeks until able to fly to water.

conservation status

Common to abundant throughout limited range; not threatened.

significance to humans

Important gamebird, hunted for food and sport. Presently under intensive study as subject for game management.


Spotted sandgrouse

Pterocles senegallus

taxonomy

Tetrao senegallus Linnaeus, 1771, "Senegal" = Algeria. Monotypic.

other common names

English: Saharan sandgrouse; French: Ganga tacheté; German: Wüstenflughuhn; Spanish: Ganga Moteada.

physical characteristics

About 14 in (36 cm); 8.8–12 oz (250–340 g). Both sexes mainly sandy, pinkish, or a rust-colored buff with yellowish orange throat. Female spotted blackish brown above and below; male mostly plain but lightly mottled brownish on wings, looking fairly uniform in the field. Both sexes have black center of belly and elongated, central tail feathers.

distribution

From southern Morocco, much of Sahara, through Arabian Peninsula to Iraq, Iran, Pakistan, and northwestern India.

habitat

Desert and semi-desert, usually where stony and flat with isolated patches of vegetation; sometimes in completely bare desert.

behavior

Gregarious in flocks of up to about 60, but birds congregate to drink at watering sites in flocks of several hundred about two hours after sunrise. Some birds may drink again in evening. Birds call to each other with a bubbling sound. In Egypt, may gather with flocks of crowned sandgrouse (Pterocles coronatus) to feed on grain spilled by trucks traveling from Nile to Red Sea ports. Nonbreeding flocks roost on ground in open desert, each bird making a shallow scrape.

feeding ecology and diet

Mainly small, hard seeds, including fallen grain. May feed on insects, but this needs verification.

reproductive biology

Nests in solitary pairs; makes small unlined scrape, usually among stones for camouflage. Breeds mostly March to July. Three camouflaged eggs incubated by female by day and male by night for up to 31 days. Chicks take water from male's soaked belly plumage but feed by themselves on food shown by parents. When disturbed, chicks may dig themselves into soft sand for concealment or may hide among stones.

conservation status

Common to abundant over most of range; extreme arid habitat means little contact with humans, and therefore, there is little threat to most populations. Said to be increasing in Somalia.

significance to humans

Generally small but may be hunted occasionally


Chestnut-bellied sandgrouse

Pterocles exustus

taxonomy

Pterocles exustus Temminck and Laugier, 1825, Senegal. Six subspecies.

other common names

English: Common Indian sandgrouse, common sandgrouse, Indian sandgrouse, Kenyan pin-tailed sandgrouse, lesser pintailed sandgrouse, singed sandgrouse, small pin-tailed sandgrouse, Somaliland pin-tailed sandgrouse, chestnut-breasted sandgrouse; French: Ganga à ventre brun; German: Braunbauchflughuhn; Spanish: Ganga Moruna.

physical characteristics

About 12.5 in (28 cm); 6–10 oz (170–284 g). Medium-sized; plumage mostly rich golden-buff; central, elongated tail feathers. Male has narrow, black breast-band; chestnut belly and underwing; and mottled back and wings. Female streaked and barred blackish; center of belly and underwing blackish brown; two or three narrow, brown breast-bands.

distribution

African Sahel from Senegal to Sudan and Ethiopia, northern Tanzania, Somalia, southern Arabian Peninsula, and most of Indian subcontinent.

habitat

Desert, semi-desert, dry steppe, arid scrub, and fallow fields.

behavior

Gregarious unless breeding, flocks are comprised of tens of thousands at favored drinking places. Birds forage mostly morning and evening, flying to water two to three hours after sunrise. Roost at night on ground in compact groups in open country.

feeding ecology and diet

Hard seeds, mostly grains and legumes; also said to feed on ants in Chad. Up to 10,000 seeds counted in one bird's crop.

reproductive biology

Breeds mostly May to December in Tanzania, but seasons vary in other parts of Africa according to rainfall and food supply. Breeding in India also variable but mostly February to August. Nest is shallow scrape in open, arid habitat. Clutch of three eggs incubated by male at night and female by day for about 23 days. Male waters chicks from his wet belly feathers.

conservation status

One of the most common sandgrouse in Africa and India; in no danger of decline.

significance to humans

May be hunted for food but not on large scale.


Black-bellied sandgrouse

Pterocles orientalis

taxonomy

Tetrao orientalis Linnaeus, 1758, "In Oriente" = Anatolia. Two subspecies generally recognized.

other common names

English: Imperial sandgrouse, large sandgrouse, oriental sand-grouse; French: Ganga unibande; German: Sandflughuhn; Spanish: Ganga Ortega.

physical characteristics

About 15 in (39 cm); female 10.6–16.4 oz (300–465 g), male 14.1–19.4 oz (400–550 g). Largest sandgrouse; robustly built, without elongated, central tail feathers. Male rust-colored buff above, mottled grayish on back and wings; throat a bright rusty color with triangular black patch; breast gray, bordered with narrow, black band and broad, pinkish band; belly black. Female similar to male but less strongly tinged rust coloring; lacks rust coloring and black on throat; breast spotted black; narrow black collar on throat and below breast. Underwing white in both sexes.

distribution

North Africa from Canary Islands and Morocco to Libya; Iberian Peninsula; discontinuously from Turkey to southwestern Russia, Iran, Afghanistan, Pakistan, and northwestern India.

habitat

Grassy steppe and semi-desert with scattered clumps of grass and herbs.

behavior

Gregarious except when breeding; flocks may number thousands at drinking sites but usually not more than about 30 birds on feeding grounds. Usually drinks a couple of hours after sunrise. Normally lands a small distance from water's edge before running down to drink, then takes off directly from water's edge and returns to feeding areas.

feeding ecology and diet

Mostly seeds, especially legumes. May also eat termites. Up to 30,000 seeds taken from single crop.

reproductive biology

Solitary nester, mostly from March to September. Nest is scrape on ground, often under a shrub. Three well camouflaged eggs incubated by female during day and by male at night for about 23–28 days; male provides young with water from soaked belly feathers.

conservation status

Abundant over most of range but may be increasingly scarce in Spain and Portugal. Becoming increasingly scarce on Fuerteventura in the Canaries.

significance to humans

Highly prized by sportsmen.


Lichtenstein's sandgrouse

Pterocles lichtensteinii

taxonomy

Pterocles lichtensteinii Temminck, 1825, Nubia. Four subspecies usually recognized.

other common names

English: Abyssinian sandgrouse, close-barred sandgrouse, Somaliland sandgrouse, Suk sandgrouse; French: Ganga de Lichtenstein; German: Wellenflughuhnl; Spanish: Ganga de Lichtenstein.

physical characteristics

About 9.8 in (25 cm); 6.2–8.8 oz (175–250 g). Smallish, without elongated, central tail feathers. Both sexes strongly barred black on buff above and below; male distinguished by black-and-white forehead pattern, yellow bill, and two broad breast-bands of buff, each bordered black below. Downy chick, unusual in being almost plain brown; other sandgrouse chicks boldly patterned above.

distribution

Discontinuous from Mauritania to Ethiopia and Somalia, central Kenya, southern Arabian Peninsula, Socotra Island, and North-West Frontier province of Pakistan.

habitat

Extreme rocky or scrubby desert hillsides and dry washes; avoids open desert and cultivated fields.

behavior

Most desert-adapted sandgrouse. Normally in pairs or small groups by day, gathering into larger flocks at dusk to fly to water. Lands a few yards from water, then runs down to drink.

Kidney structure is especially well adapted to water conservation; water-carrying capacity of male's belly plumage is greatest for any sandgrouse studied. Largely nocturnal, roosting by day in shade of rocks or plants.

feeding ecology and diet

Small, hard seeds, especially of Acacia sayal and other legumes.

reproductive biology

Breeds mainly May to July, rarely to September. Nest is shallow scrape among scattered rocks and vegetation. Two or three camouflaged eggs form usual clutch but little else known.

conservation status

Common over most of range. Very arid habitat provides best protection from humans.

significance to humans

Probably very little contact with humans because of extreme habitat preference.


Pallas's sandgrouse

Syrrhaptes paradoxus

taxonomy

Syrrhaptes paradoxus Pallas, 1773, southern Tartarian Desert. Monotypic.

other common names

French: Syrrhapte paradoxal; German: Steppenhuhn; Spanish: Ganga de Pallas.

physical characteristics

15–16 in (38–40.6 cm); male 8.8–10.6 oz (250–300 g), female 7.1–9.2 oz (200–260 g). Medium-sized with very long, central

tail feathers and white underwing in both sexes. Male mostly rich orange-buff above, coarsely barred with black on back; throat rich tawny; breast buffy gray with scalloped band of black and white in center; belly black. Female buff above, heavily barred with black; below mostly buffy gray; belly black. Hind toe absent; legs and feet feathered, except for soles of toes.

distribution

Southern Russia from Caspian Sea to China, including Tibet, and Mongolia. Irrupts sporadically into Europe and British Isles, most recently in 1908.

habitat

Open steppe and sandy desert, often with wormwood (Artemisia) scrub. In summer, mostly between 4,300 and 10,500 ft (1,300 and 3,200 m) but may move to lower elevations in winter.

behavior

Gregarious when not breeding; sometimes in flocks of hundreds, especially on migration, though most populations are sedentary or locally nomadic. Wings have specialized outermost primaries that produce whistling in flight. Flies to water at any time of day but mostly before mid-morning.

feeding ecology and diet

Seeds, mostly of legumes. Some green shoots may also be taken.

reproductive biology

Nesting occurs mostly from April to June; nesting pairs generally solitary, but adjacent nests may be only 13–20 ft (4–6 m) apart. Nest scrape is on ground among vegetation or in open. Three eggs incubated for 22–26 days. The roles of the sexes unknown in the wild, but in captivity only female incubates both day and night; male sits near female most of time but not on nest. Nothing known of care of the young.

conservation status

Highly adaptable. Seems to be able to maintain numbers, even in agricultural areas; in no need of special conservation measures.

significance to humans

Possibly hunted for food but appears not to be considered important game bird.


Resources

Books

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

Feduccia, Alan. The Origin and Evolution of Birds. 2nd ed. New Haven: Yale University Press, 1999.

Johnsgard, Paul A. Bustards, Hemipodes, and Sandgrouse: Birds of Dry Places. Oxford: Oxford University Press, 1991.

Maclean, Gordon Lindsay. Roberts' Birds of Southern Africa. 6th ed. Cape Town: John Voelcker Bird Book Fund, 1993.

Maclean, G.L., and C.H. Fry. "Pteroclidae, sandgrouse." In The Birds of Africa, Vol. 2., edited by Emil K. Urban, et al. London: Academic Press, 1986.

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

Periodicals

Cade, T.J., and G.L. Maclean. "Transport of water by adult sandgrouse to their young." Condor 69 (1967): 323–343.

Kalchreuter, Heribert. "The breeding season of the chestnut-bellied sandgrouse Pterocles exustus and the black-faced sandgrouse P. decoratus in northern Tanzania and its relation to rainfall." Proceedings of the 4th Pan-African Ornithological Congress (1976): 277–282.

Lloyd, Penn, et al. "Rainfall and food availability as factors influencing the migration and breeding activity of Namaqua sandgrouse Pterocles namaqua." Ostrich 72, no. 1 and 2 (2001): 50–62.

Maclean, G.L. "Die systematische Stellung der Flughühner (Pteroclididae)." Journal für Ornithologie 108 (1967): 203–217.

Maclean, G.L. "Field studies on the sandgrouse of the Kalahari Desert." Living Bird 7 (1968): 209–235.

Maclean, G.L. "Adaptations of sandgrouse for life in arid lands." Proceedings of the 16th International Ornithological Congress (1974): 502–516.

Maclean, G.L. "Evolutionary trends in the sandgrouse." Malimbus 6 (1984): 75–78.

Maclean, G.L. "Sandgrouse: models of adaptive compromise." South African Journal of Wildlife Research 15 (1985): 1–6.

Simiyu, A. "Some aspects of demography and movement patterns of sandgrouse in southern Kenya." Ostrich 69, no. 3 and 4 (1998): 452.

Thomas, D.H. "Adaptations of desert birds: sandgrouse (Pteroclididae) as highly successful inhabitants of Afro-Asian arid lands." Journal of Arid Environments 7 (1984): 157–181.

Organizations

African Gamebird Research, Education and Development (AGRED). P.O. Box 1191, Hilton, KwaZulu-Natal 3245 South Africa. Phone: +27-33-343-3784. E-mail: [email protected] botzoo.uct.ac.za

Other

Lloyd, Penn, et al. "The population dynamics of the Namaqua sandgrouse: implications for gamebird management in an arid, stochastic environment." Proceedings of the 22nd International Ornithological Congress, Durban, South Africa. Compact disk. Johannesburg: BirdLife South Africa, 1999.

Gordon Lindsay Maclean, PhD, DSc

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