Woodswallows (Artamidae)

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Woodswallows

(Artamidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Artamidae


Thumbnail description
Gregarious aerial foragers; mostly some combination of gray, black, and white, with pointed wings and short, stumpy tails

Size
4.7–7.9 in (13–20 cm); 0.5–1.6 oz (13–46 g)

Number of genera, species
1 genus; 11 species

Habitat
Woodswallows are birds of the open forest and woodlands, scrub, and clearings

Conservation status
Not threatened

Distribution
Six species occur in Australia, others through the islands of the South Pacific, across south China to India and Sri Lanka

Evolution and systematics

The taxonomic status of the woodswallows, sometimes called swallow-shrikes, is still under debate. Sibley and Monroe, grouped the woodswallows with the currawongs in the tribe Artamini, subfamily Corvinae, of the family Corvidae, and included several other genera on the basis of DNA-DNA hybridization data. Christidis and Boles in their standard 1994 classification of Australian birds included the woodswallows, butcherbirds, Australian magpies, and currawongs in the family Artamidae. Most recently, Schodde and Mason in their 1999 The Directory of Australian Birds: Passerines follow Christidis and Boles except for the order of genera.

Physical characteristics

Woodswallows are swallow-like birds with pointed wings and short tails that forage mainly by soaring and sweeping up flying insects. They are mostly subtle combinations of gray, white, and black, with several species having russet tones as well. Most species have white-tipped tails.

Woodswallows are the only passerines that have powder down patches of feathers that disintegrate into a soft powder that the birds use in grooming feathers in a manner analogous to preen gland secretions in other passerines. They have pointed wings with a vestigial outermost primary, short toes, and weak-grasping feet.

Distribution

Some species are widely distributed, e.g., the ashy woodswallow (Artamus fuscus) is found in the lowlands of southern Asia from India through southern China, while others have limited distribution, e.g., the Bismark woodswallow (Artamus insignis) is restricted to the Bismark Archipeligo. Six species are found in Australia, four of them endemic.

Habitat

Woodswallows are found in a broad spectrum of habitats throughout their range including mangroves, open areas, orchards, towns, open woodlands, forests, and forest edge.

Behavior

Highly gregarious, some woodswallow species are nomadic and travel in flocks of a hundred or more. They sometimes roost communally, with dozens of birds huddling together, perhaps to help with thermoregulation. When not foraging, they may cluster in large numbers on tree branches or wires. In winter they often join mixed species foraging flocks. They utter frequent soft contact calls, and may mob potential predators, while making harsh calls.

Feeding ecology and diet

Although woodswallows are primarily aerial foragers, sweeping flying insects from the canopy and above, they also are proficient ground pouncers, dropping from tree limbs to capture a grasshopper or caterpillar from open ground. These versatile foragers also take nectar and pollen.

Reproductive biology

Many species are opportunistic breeders, well adapted to an unpredictable environment, settling down to nest in loose

colonies whenever rains come to arid areas. Nests are usually shallow, flimsy bowls of woven plant fibers including rootlets, twigs, and grass, placed in trees, shrubs, stumps, fence posts, or in rocky crevices. The usual clutch is two to four white eggs spotted or blotched with a variety of colors. Both parents incubate for 12–16 days. Fledging occurs 14-20 days later. Both parents and sometimes a helper feed the young.

Conservation status

Species with broad distributions are not threatened, but species with restricted distributions may be adversely affected by habitat alteration and human disturbance. At present, no woodswallows are considered threatened.

Significance to humans

Woodswallows are highly visible and asthetically pleasing birds, their soft, subtle coloration and dynamic flight making them favorites to many.

Species accounts

List of Species

Black-faced woodswallow
Little woodswallow
Dusky woodswallow
White-breasted woodswallow
White-browed woodswallow

Black-faced woodswallow

Artamus cinereus

taxonomy

Artamus cinereus Vieillot, 1817, Timor. Four subspecies.

other common names

French: Langrayen gris; German: Schwarzgesicht-Schwalbenstar; Spanish: Golondrina del Bosque de Cara Negra.

physical characteristics

7.1–7.5 in (18–19 cm); 1.1–1.4 oz (32–40 g). A. c. normani and A. c. dealbatus both have white undertail-coverts, the other subspecies have black. Sexes similar in plumage; gray with black face, silvery underwings, and broad white spots at tip of tail. Juvenile birds are brown and streaked.

distribution

Broadly distributed across Australia. A. c. normani and A. c. dealbatus, the two white-vented subspecies, are found respectively on the Cape York Peninsula and the northeastern Queensland coastal belt. A. c. cinereus is confined to southwestern Western Australia, and A. c. melanops is also found in the Lesser Sunda Islands, including Timor.

habitat

Occupy a broad range of habitats, often arid and far from water, including open eucalypt woodlands, scrub, and spinifex.

behavior

Partly nomadic and an opportunistic breeder; mostly sedentary. Often roost in small flocks tightly clustered. Voice is a sweet chatter.

feeding ecology and diet

Primarily aerial feeders, soaring and swooping after flying insect prey. They take ground invertebrates, glean vegetation, and sometimes take flower nectar.

reproductive biology

May breed at any time of year after rains when insects become abundant. Courtship displays include wing-waving and tail-rotating, displaying their white patches at the tip of their tails. Nest is a flimsy bowl of plant fibers placed in any available crevice. Clutch is three to four blotched white eggs. Incubation lasts 14–16 days, and fledging occurs 18 days later. They may have helpers at the nest.

conservation status

Not threatened.

significance to humans

None known.


Little woodswallow

Artamus minor

taxonomy

Artamus minor Vieillot, 1817, Shark's Bay, Western Australia. Two subspecies.

other common names

French: Petit Langrayen; German: Zwergschwalbenstar; Spanish: Golondrina del Bosque Pequeña.

physical characteristics

4.7–5.1 in (12–13 cm); 0.5–0.6 oz (13–16 g). Chocolate-brown body with dark gray wings and tail; tail spotted white at tip. Juveniles brown and streaked.

distribution

Australian endemic. A. m. minor is found in Western Australia, and the central arid regions of northern Southern Australia and southern Northern Territory. A. m. derbyi is found in northern Australia from northern Western Australia to northern New South Wales.

habitat

Rocky outcrops and gorges, in open arid woodland and acacia scrub.

behavior

Sedentary over much of its range. Some eastern populations are nomadic and may be locally migratory. Lives in family groups of up to several dozen birds. Roosts communally. Voice consists of soft contact calls.

feeding ecology and diet

Sweep flying insects around cliff faces in flight. Will also forage on ground and glean foliage; sometimes take nectar.

reproductive biology

Nest is built by both parents and is a flimsy cup tucked in a rock crevice or stump. Clutch is two to three splotched white eggs. Both parents care for young.

conservation status

Not threatened.

significance to humans

None known.


Dusky woodswallow

Artamus cyanopterus

taxonomy

Artamus cyanoptera Latham, 1801, Sydney, New South Wales, Australia. Two subspecies.

other common names

French: Langrayen sordide; German: Russchwalbenstar; Spanish: Golondrina del Bosque Ahumada.

physical characteristics

6.7–7.1 in (17–18 cm); 1.1–1.6 oz (31–46 g). Smoky-brown body, dark gray wings and tail; wings edged in white, distinctive white spots at end of tail. Underwings silvery.

distribution

Australian endemic. A. c. perthi is resident in southwest Australia. A. c. cyanopterus is found in eastern South Australia up to southern Queensland, including Tasmania, but migrates north in winter.

habitat

Found in eucalypt forests and woodlands, along water courses, and over natural clearings. Tend to prefer rural areas, and wetter habitat than most woodswallows.

behavior

Tends to live in small groups of several dozen birds. Social and gregarious, often roosting in a cluster in a tree hollow. Birds often perch close together while resting during the day. Chattering contact call, harsh mobbing call.

feeding ecology and diet

Primarily an aerial feeder. Will also glean foliage, take ground insects and occasionally nectar.

reproductive biology

Both parents build the flimsy cup nest of plant fibers. Nests are built in loose colonies, with territory around the nest defended. May be cooperative breeders, with helpers at the nest. Clutch is three to four blotched white eggs. Incubation is for 16 days, and fledging occurs 16–20 days after hatching.

conservation status

Not threatened.

significance to humans

None known.


White-breasted woodswallow

Artamus leucorynchus

taxonomy

Artamus leucorynchus Linnaeus, 1771, Manila, Luzon.

other common names

French: Langrayen à ventre blanc; German: Weissbauch-Schwalbenstar; Spanish: Golondrina del Bosque de Pecho Blanca.

physical characteristics

6.7–7.1 in (17–18 cm); 1.3–1.6 oz (36–46 g). Gray hood, back, and tail, with white below and white rump diagnostic. Lacks white tail spots of most species.

distribution

Widely distributed in Southeast Asia, from Malay Archipelago, and islands of Oceania including Philippines, Moluccas, Greater and Lesser Sundas, New Caledonia, and New Guinea. In Australia, coastal and along rivers from Shark Bay, Western Australia, along northern edge to east coast as far south as Sydney. Usually close to water.

habitat

Predominately tropical woodlands, open areas, scrub, mangroves, and settled areas. It occurs in most habitat types.

behavior

Largely sedentary, but seasonally nomadic with some winter migratory movements to the north. Very social and gregarious with flocks of several hundred not uncommon. They huddle together on branches or wires. Chattering contact call, harsh warning call.

feeding ecology and diet

Forage mostly by soaring through or above canopy. They take ground prey by pouncing, or glean foliage; have been reported taking nectar from flowers.

reproductive biology

Lack white tail spots of other woodswallows, and do not use tail in courtship displays. Both parents build flimsy bowl nest of plant fibers, and care for young. Clutch is three to four blotched white eggs, and incubation lasts 13–15 days.

conservation status

Not threatened.

significance to humans

None known.


White-browed woodswallow

Artamus superciliosus

taxonomy

Artamus superciliosus Gould, 1837, Hunter River, New South Wales, Australia.

other common names

French: Langrayen bridé; German: Weissbrauen-Schwalbenstar; Spanish: Golondrina del Bosque de Cejas Blancas.

physical characteristics

7.5–7.9 in (19–20 cm); 1.1–1.3 oz (32–38 g). Male gray above, chestnut below, highlighted by white-eyebrow stripe, and white corners to tail. Female, colors muted; juvenile brown and streaked.

distribution

Nomadic species found throughout much of the eastern half of Australia, primarily away from the coast.

habitat

Occupies highly diverse habitat, from eucalypt forests and woodlands to arid spinifex, heathlands, and settled areas including orchards and farmlands.

behavior

Highly nomadic, flocks often contain several woodswallow species. Opportunistic breeder, with flocks settling in areas where insects are abundant or where recent rains have occurred. Chattering contact calls are frequent among flock members, and they frequently cluster together at roost.

feeding ecology and diet

A predominately aerial forager, endlessly swooping and soaring, taking flying insects. Will take insects from ground or foliage, and flower nectar.

reproductive biology

Usually nest in loose colonies, often opportunistically after rainfall. Both parents build flimsy nest of plant fibers placed in crevice. Clutch is usually two to three blotched white eggs; incubation lasts about 16 days and fledging occurs after about two weeks, although young stay with parents considerably longer.

conservation status

Not threatened.

significance to humans

None known.


Resources

Books

Christidis, L., and W.E. Boles. The Taxonomy and Species of Birds of Australia and Its Territories. Hawthorn East, Victoria, Australia: Royal Australasian Ornithologists Union Monograph 2, 1994.

Pizzey, G., and F. Knight. The Graham Pizzey and Frank Knight Field Guide to the Birds of Australia. Sydney: HarperCollins, 1997.

Schodde, R., and I.J. Mason. The Directory of Australian Birds: Passerines. Canberra: CSIRO Wildlife and Ecology, 1999.

Schodde, R., and S. C. Tidemann, eds. Reader's Digest Complete Book of Australian Birds. 2nd ed. Sydney: Reader's Digest Services, 1986.

Sibley, C.G., and B.L. Monroe, Jr. Distribution and Taxonomy of Birds of the World. New Haven: Yale University Press, 1990.

Simpson, K., and N. Day. Birds of Australia. Princeton: Princeton University Press, 1999.

Strahan, R., ed. Finches, Bowerbirds and Other Passerines of Australia. Sydney: Angus & Robertson, 1996.

William E. Davis, Jr.

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