Magpie-Shrikes (Cracticidae)

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Magpie-shrikes

(Cracticidae)

Class Aves

Order Passeriformes

Suborder Passeri (Oscines)

Family Cracticidae


Thumbnail description
Crow- to flycatcher-sized pied or dusky, stout-billed songbirds adapted to diverse niches in trees and on the ground

Size
6.5–22 in (17–55 cm); 1.1–17.5 oz (30–500 g)

Number of genera, species
5 genera; about 14 species

Habitat
Treed habitat on land, including rainforests, savannas, and pastures with trees

Conservation status
Near Threatened: 1 species; Data Deficient: 1 species

Distribution
Australia and New Guinea, with one outlying species in Borneo

Evolution and systematics

No other family of Australasian birds has radiated into so many niches in so few species as the magpie-shrikes. The family's butcherbirds are tree-living, shrike-like predators; its magpies are ground-foraging invertebrate feeders; its currawongs are scavenging generalists; and its peltopses are flycatcher-like, sallying insectivores. Despite such diversity, the group remains similar in skeletal structure, which is characterized by stout, straight, heavily ossified predatorial bills and elongated palates. Due to fusion in the nasal aperture, a massive shelf is formed in the roof of the mouth, an unusual trait in songbirds. The family is a branch of a massive radiation in crow-like birds that arose in Australia in the early to mid-Teriary, 30–40 million years ago. Unlike many others, however, it remained centered on the Australian plate. Only one member occurs outside Australia-New Guinea today, the bristlehead (Pityriasis) in Borneo.

Gradual drying in the Australian climate over the last 20 million years drove the diversification of the magpie-shrikes. Scavenging currawongs and ground-feeding magpies, derived from tree-living ancestors that resembled butcherbirds, are centered today in the drier eucalypt woodlands there. Even modern butcherbirds are more diverse in that habitat than in the remnants of ancestral subtropical rainforest along the east Australian coast and mountain regions of New Guinea.

Physical characteristics

Magpie-shrikes are large songbirds with pied (black-and-white) or blackish plumage and straight, powerful bills. Color is varied with red in only two groups: on the rump, lower belly, and undertail in peltopses and over the head in the bristle-head. Bristleheads are otherwise dusky-gray, stout, and short-tailed, while the small, flycatcher-like peltopses are long-tailed and black with large patches of white on their faces and backs. Currawongs, however, are big but slender crow-sized birds with long, white-tipped tails, rounded wings, startling yellow eyes, and dark gray to blackish plumage broken by patches of white in wings and under the tail. Australian magpies are pied, with black undersurfaces and pied uppersurfaces, and are short in tail, pointed in wing, and long in leg–all adaptations to life in open spaces. Although also basically pied, butcherbirds vary more, from all-black to black-hooded with white patches to wholly white with black, gray, and white patterning. Like magpies, butcherbirds are mid-sized magpie-shrikes with chestnut eyes and bicolored bills; the tip of the bill is blackish and the base whitish or pale bluish gray, while the bills in currawongs, peltopses, and bristleheads are black. Juveniles share the adults' plumage, although it is much duller and grayer, particularly in some butcherbirds. Depending on species or subspecies, fledglings may be rusty-brown, washed olive-yellow, or lack clear head-patterning. They also have uniformly dull gray bills.

Size varies from small (6.7–7.9 in [17–20 cm] long, 1.1–1.2 oz [30–35 g]) in the peltopses to very large in the Tasmanian gray currawong, Strepera versicolor arguta (19.7–21.7 in [50–55 cm] long, 16.2–17.6 oz [460–500 g]). As with most other crow-like birds, magpie-shrikes have a single pneumatic depression in the head of the humerus, as well as 12 tail feathers, 10 primary flight feathers (the tenth is usually well-developed), and 10 secondaries (11 in the Australian magpie). Also characteristic are the lack of a gap in the dorsal (back) feather tract and small perforations in the skull above the opening for the nerves of the eye; unusually strong black feet with booted or scaled legs; and powerful bills that range from notched and hooked to pick-shaped at the tip and are swollen at the base of the upper jaw, which lacks bristles and in which the nostrils are sunk in deep bony slits.

Distribution

Except for the bristlehead in the lowlands of Borneo, magpie-shrikes are restricted to Australia and New Guinea and their in-shore islands. Peltopses are endemic to New Guinea, with one species occurring throughout the lowlands and the other in mountain ranges up to 9,900 ft (3,000 m) above sea level. In contrast, currawongs are endemic to Australia, restricted to southern and east coast Bassian regions north to Cape York Peninsula. The Australian magpie is also centered in Australia but, being adapted to open environments, ranges throughout the continent, with outliers in east Tasmania and the central portion of southern New Guinea. Only butcherbirds are represented by species in both Australia and New Guinea.

Habitat

Magpie-shrikes occur in wooded habitats that vary according to the foraging niches of the birds. Bristleheads occupy the mid-strata of mature, lowland alluvial (relating to river and lake systems) and swamp rainforests, while peltopses in New Guinea live on the edge of the canopy in both mature and regrowth rainforest. Currawongs are as much scansorial (adapted for surface-foraging) as arboreal (tree-dwelling) in their feeding and work over foliage, branches, bark, and ground in habitats ranging from dense, tall, wet forests to open, low, eucalypt-dominated woodlands. Australian magpies occupy even more open habitat, centering on savannas and pastures, whereas the wholly arboreal butcherbirds occupy the middle and upper strata of forests and woodlands. Butcherbird species coexist in any one region by partitioning their habitat. The black butcherbird and New Guinean members of the black-hooded groups occur in rainforests, the former at all strata within mature forests and in mangroves, and the latter in the middle and upper strata at forest edges and in secondary growth. In Australia, the three gray-group species occupy drier eucalypt forests and thickets, replacing one another in different parts of the continent. Where it overlaps them, the Australian member of the black-hooded group (Cracticus nigrogularis) keeps to more open woodlands.

Behavior

Reflecting adaptations to niche, behaviors are diverse. Tree-living butcherbirds, bristleheads, and New Guinean peltopses are perch-pouncers or salliers, using their feet for little else besides perching, coming to the ground only to snatch prey. All are sedentary, keeping to the same large foraging territories year-round, and are solitary, rarely gathering in groups larger than family parties. In flight, they move between trees in direct flight on rapidly and shallowly flapping wings. Similarly sedentary, the ground-feeding Australian magpie is more gregarious and has evolved a complex social organization; senior pairs or small breeding groups hold permanent territory in optimal habitat, while larger groups of juveniles and subordinate nonbreeders congregate in suboptimal areas. On the ground, magpies walk sedately, and their flight, direct as in butcherbirds, is far swifter. Currawongs are variably social, the gray being solitary at all times, while the other two species gather in large wandering bands when not breeding. At that time, their east coast populations make north to south migratory movements. Currawongs bound about all strata in the forest and hop and run on the ground. These long-tailed birds also fly in loping undulations.

Loud, carrying flutings, glottal (relating to the opening between the vocal chords and larynx) gargles, and bell-like whistles characterize the calls of all magpie-shrikes except the peltopses, which "tick" or "tinckle" mechanically. Australian magpies often chorus together in groups, and flocking currawongs call and answer constantly.

At night, all magpie-shrikes roost in tree foliage at mostly mid-height, Australian magpies and flocking currawongs doing so in loose groups.

Feeding ecology and diet

Magpie-shrikes are predatory passerines that have radiated into a range of foraging niches. Bristleheads are arboreal insect gleaners. Peltopses are arboreal, flycatcher-like salliers of the top and edge of forest canopies, again taking mainly insects. Butcherbirds are more shrike-like, hunting through the mid-strata of forests and woodlands by perching and pouncing, capturing a range of arthropods, small vertebrates, and crustacea in trees and on the ground. They wedge or impale larger prey in crannies and on spikes for tearing with their well-hooked bills before eating. Australian magpies, however, are strict ground-feeders, digging for grubs, worms, and other ground-burrowing invertebrates with their stout bills. Currawongs are opportunistic generalists, particularly the pied currawong (Strepera graculina), moving over the ground and through trees and shrubbery to dig, prize, and scavenge for invertebrates, small vertebrates, nestlings, eggs, and berries. Males of most species also have significantly longer, but hardly thicker, bills than females, suggesting some sexual partitioning in feeding.

Reproductive biology

Although breeding may occur erratically year-round in tropical regions, it is restricted from early spring through summer (August to January) in temperate and subtropical Australia. Rarely more than one brood is raised a year. Most species are monogamous, except the polygynous Australian magpie, and breed in pairs; all appear to be strictly territorial. Only the female builds the nest, a rough cup of twigs and rootlets lined with finer fiber, in horizontal to upright forks in the upper branches of trees; and she incubates alone, fed on or off the nest by the male. Clutches are of one to five eggs, cream or pinkish buff to pale green, lined or spotted with red-browns and gray-blacks.

Conservation status

Because it is limited to mature rainforests, particularly dipterocarp-dominated swamp forests that are subject to deforestation for timber, the Bornean bristlehead is classified as Near Threatened. It seems to be the only species under serious threat. Categorized as Data Deficient, the Tagula butcherbird (Cracticus louisiadensis) is also listed, presumably because it is restricted to one small island off southeastern New Guinea. Even so, it is a member of the black-hooded butcherbird group that is well-adapted to secondary growth and forest disturbance.

Significance to humans

No magpie-shrikes have made a significant impact on humans except for the Australian magpie. This species, which is widely appreciated in Australia for its fearlessness and caroling song, is cultivated around rural properties and fed in urban areas, and has been introduced successfully to New Zealand, the Solomon Islands (Guadalcanal), Fiji (Taveuni),

and several offshore Australian islands. When breeding, rogue males can become a problem, diving to attack children and others. The skulking pied currawong (Strepera graculina) has also invaded towns and cities along the east coast of Australia, impacting on smaller birds of all species by robbing nests and taking newly fledged young.

Species accounts

List of Species

Bornean bristlehead
Clicking peltops
Gray butcherbird
Australian magpie
Pied currawong

Bornean bristlehead

Pityriasis gymnocephala

subfamily

Pityriasinae

taxonomy

Barita gymnocephala Temminck, 1835, Borneo. Monotypic.

other common names

English: Bald-headed woodshrike; French: Barite chauve; German: Warzenkopf; Spanish: Alcaudón de Borneo.

physical characteristics

10–11 in (26–28 cm). Thickset, massive-billed, and stumpy-tailed. Dusky body; black wings, tail, and bill; and red, mostly bare head with a patch of orange-yellow stubble on the crown, another of streaky brown over the ears, and a fringe of scarlet feathering on upper back and breast; lower breast also covered in bristle-like brown and red feathers. Females have a red patch on the flanks. Eyes are chestnut and feet distinctively yellow.

distribution

Lowland Borneo up to altitudes of about 3,900 ft (1,200 m).

habitat

Mature lowlands and swamp rainforests.

behavior

Patchy throughout range, bristleheads appear to reside in one area, where they work through the mid-strata of forests in noisy groups. Little is known of their behavior. They are ponderous in movement, hopping among branches and crouching

and peering into crannies in search of food. Flight is direct, on fast and shallowly beating wings. Calls, presumably given for social cohesion, comprise strange nasal whines, honks, and chortles; members of a group also will chorus, jumbling calls loudly together.

feeding ecology and diet

Primarily predatory insectivores, gleaning gregariously among branches and trunk crannies in forest midstage for food. Diet comprises large insects, such as arboreal beetles, grasshoppers, bugs, cockroaches, and larvae. Birds will also gather around recent clearings in search of exposed food.

reproductive biology

Little is understood about pair bonding and nest-building duties, nor is the nest and its site described. Eggs are whitish, sparingly blotched with rich brown and slate-gray mostly at the larger end.

conservation status

Listed as Near Threatened due to occurrence in mature rain-forests in areas under threat of extensive deforestation.

significance to humans

None known.


Clicking peltops

Peltops blainvillii

subfamily

Cracticinae

taxonomy

Eurylaimus blainvillii Lesson and Garnot, 1827, Dorey, West Papua. Monotypic. This is the lower altitude member of a pair of sibling species that replace one another altitudinally throughout mainland New Guinea. Despite similarity in appearance and foraging ecology, the two have distinct contact/advertising calls.

other common names

French: Peltopse des plaines; German: Waldpeltops; Spanish: Peltopo del Valle.

physical characteristics

6.5–7.3 in (17–18 cm); 1.1–1.2 oz (30–35 g). Stout, black, redeyed flycatcher-like bird with slender tail; patches of white over the ears and on the upper back; and crimson on belly, undertail, and rump. Sexes are alike but juveniles duller. Differs from its montane (mountain-dwelling) sibling species, Peltops montanus, in its slightly smaller size, shorter tail, smaller white patches over ears and on back, and much heavier, broader bill.

distribution

Lowland New Guinea and western Papuan islands up to about 1,640 ft (500 m) above sea level.

habitat

Primary and tall secondary rainforests, particularly along edges and around openings such as tree falls, stream edges, and road cuttings. Densities have been estimated at two birds per 25 acres (10 ha) in suitable habitat.

behavior

Widely but sparsely distributed year-round residents; solitary, in loose pairs or small family groups of three to five. Live mostly in top of forest canopies, perching upright and motionless for long periods on exposed vantage perches, from which they fly out in extended sallies. From perches and in flight, birds utter distinctive territorial and advertising calls at regular intervals; calls are a series of three or so well-spaced mechanical double clicks over four to five seconds. At perches, the singer throws its head violently up and down at each click. Other calls include a harsh monarch-like wheeeit, possibly in warning or agitation, and a seldom-heard wren-like twittering.

feeding ecology and diet

Apparently wholly insectivorous, birds capture food in the air and from the surface of foliage with the bill on sallying flights. Most foraging is done in and above the forest canopy but sometimes extends to lower strata. Food, including dragonflies, beetles, grasshoppers, and other flying insects, is swallowed whole at a perch, without much beating.

reproductive biology

Data lacking on timing and duration of events and respective parental contribution. Nests are small, compact cups of twigs and rootlets built in often exposed positions in horizontal tree forks at the ends of branchlets at 20–115 ft (6–35 m) above the ground; and eggs, usually one per clutch, are cream to pale buff, with a ring of black-brown spotting at the larger end.

conservation status

Not threatened.

significance to humans

None known.


Gray butcherbird

Cracticus torquatus

subfamily

Cracticinae

taxonomy

Lanius torquatus Latham, 1802, Port Jackson (Sydney), Australia. Three, possibly four subspecies; one large and dark with reduced white in wing in Tasmania (Cracticus torquatus cinereus), another small and dark with reduced white in wing in coastal southeastern Australia between the New South Wales-Queensland border and Melbourne (nominate torquatus), and a third (that may comprise east and west forms) small and paler with extensive white in wing throughout southern and inland Australia from the west coast to coastal Queensland south of Cape York Peninsula (C. t. leucopterus). The gray butcherbird forms a superspecies with the silver-backed butcherbird (C. argenteus) of northwestern Australia and the black-backed butcherbird (C. mentalis) of Cape York Peninsula and dry sectors of southeastern New Guinea.

other common names

French: Cassican à collier; German: Graurücken-Würgatzel; Spanish: Pájaro Matarife Gris.

physical characteristics

10–12 in (25–30 cm); 2.8–4.0 oz (80–110 g). Medium-sized bull-headed bird with tapered body and black-, gray-, and white-patterned plumage. Head black with white lore spot (between eye and upper bill) and collar, back gray, rump white, tail and wings black with white tips and stripes respectively, and undersurface uniformly grayish white. Eyes dark brown, feet gray, and bills bicolored, with black tip and gray-white base. Females are usually grayer breasted and shorter billed than males. Juveniles dull-gray-billed and dully patterned, with dusky-olive and speckled upperparts and yellowish underparts.

distribution

Most of southern and inland Australia north to 20°S, including Tasmania but excluding treeless deserts.

habitat

Closed woodland and open forest of eucalypts and acacias, including mallee (Eucalyptus) and mulga (Acacia) scrubs, where the space between tree crowns is about the size of the crowns themselves. Densities range from one bird to about 12 to 49 acres (5–20 ha) in suitable habitat.

behavior

Retiring and solitary, in pairs or small family groups, gray butcherbirds live in the mid- and upper strata of trees, spending much of their time perching still and coming to ground only to pounce on prey. They are sedentary, with pairs holding the same territory, 20–99 acres (8–40 ha), year-round, with a larger home range. Both male and female duet antiphonally in songs of fluted whistles and ringing caws, which are also given in alarm and aggression.

feeding ecology and diet

Gray butcherbirds are raptorial perch-pouncers, watching from tree perches at 6.5–40 ft (2–12 m) up, then swooping down to ground or branches to snap up prey, which is mostly insects but also small birds, nestlings, reptiles, and mice. Fruit also contributes to the diet. Food is carried back to perch, wedged in crannies or forks and torn apart with the bill for eating; the small weak feet are not used for tethering prey.

reproductive biology

Monogamous, forming pair bonds in breeding territories reinforced by much duetting during early breeding. Gray butcherbirds breed mostly between July and August and December and January throughout their range. The nest, a rough but tight cup of twigs lined with finer, often reddish fiber, is placed in upright forks in outer foliage at 10–50 ft (3–15 m) up and takes about four weeks to build. Eggs, in clutches of three to five, are 1.20–1.25 × 0.85–0.95 in (30–32 × 22–24 mm), brownish green, and finely freckled in red-browns, often in a zone around the larger end; they hatch in 22–24 days. Female builds nest and incubates unaided, while the male defends territory. He may assist her in feeding young, which fledge around four weeks. Usually, only one brood reared per year.

conservation status

Not threatened, although many populations have declined locally because of habitat clearing and alienation.

significance to humans

Some local populations frequent camping sites, feeding on scraps and garbage thrown out by campers. They are called commensals in such circumstances because they benefit from a close association with humans.


Australian magpie

Gymnorhina tibicen

subfamily

Cracticinae

taxonomy

Coracias tibicen Latham, 1802, Port Jackson (Sydney), Australia. Polytypic with up to nine subspecies, the limits and identity of which are controversial. Subspecies differ mainly in pattern of back, whether white or black; size; proportions of bill; and width of the black band on the tail tip. Four black-backed subspecies occur across northern Australia south to the Pilbara in the west and the Murray-Darling Basin and south coastal New South Wales in the east; five white-backed subspecies occur in southwestern and southeastern Australia, including Tasmania, with an outlier in central southern New Guinea. Opinion has varied over whether white- and black-backed groups are distinct species, but they hybridize freely wherever they meet. Intriguingly, the white-backed subspecies in southwestern Australia and southern New Guinea have blackishbacked females.

other common names

French: Cassican flûteur; German: Flötenvogel; Spanish: Urraca Canora.

physical characteristics

13–17 in (34–43 cm); 8.8–12 oz (250–340 g). Pied, longlegged, short-tailed magpie-shrikes with black heads, white uppersurface with or without a black saddle across the back, white tail with black tip, black wings with white shoulder patch, and entirely black undersurface except for white under-tail coverts; eyes chestnut, feet black, and bills bicolored with black tip and grayish white base. Females have shorter bills

than males and their dorsal white is clouded with gray; in southwest Australian females, the black feathers of the saddle are edged with white. Juveniles are much duller than adults, dingy gray-billed, and pass through gray-breasted plumage before reaching adulthood in their third or fourth year.

distribution

Throughout Australia, including east Tasmania but excluding central treeless deserts and extreme north (north Kimberley, Arnhem Land, and Cape York Peninsula), with an outlying population in dry sectors of central southern New Guinea. Introduced successfully in New Zealand, Fiji, and Guadal-canal.

habitat

Open woodlands, savannas, and rural fields with fringing trees, windbreaks, and copses. A combination of extensive bare or short-pastured ground (for feeding) and scattered groups of trees (for roosting and nesting) is essential.

behavior

Australian magpies are bold, gregarious birds in settled areas, adapting to human habitation and benefitting from the clearing of land for rural purposes. Also sedentary and hold territory year-round according to social order; top males occupy and defend optimal territories that include one to several females, while at the bottom rung are loose, locally mobile flocks (of about 10 to 100 or more) of juveniles evicted from parental territories and adults that have not yet gained or have lost territorial status. Groups sing together from perches in rich, organ-like fluted caroling to advertise territory. In group attacks on predators (e.g., raptors) often much larger than themselves, they yell in shrieking yodels, calling in mid-flight and alarming the entire neighborhood. Flight is swift and powerful on rapidly and deeply beating pointed wings. Magpies spend most of the day feeding on the ground but rest and roost on perches in trees or poles, each group sleeping as a loose unit in a single tree or series of adjacent trees.

feeding ecology and diet

Ground-foraging invertebrate feeders, Australian magpies feed on bare or short-pastured turf over which they can move easily on long legs. They walk methodically like rooks (Corvus frugilegus), head cocked, listening, and watching. Most prey, including grubs, worms, and ground and burrowing insects, is dug out of the ground with their straight, stout bills. Items are dispatched and eaten on the ground at point of capture.

reproductive biology

The breeding system is polygynous and territorial, one male mating with one to several females and spending nearly all his time defending them and his territory from other males. Breeding, from nest-building to fledging, extends from early spring to early summer (mid-July through August to December or January), in territories of 7–25 acres (3–10 ha), or more in arid areas. Only one brood is reared per year. All nesting duties are carried out by the mated female, but she may be helped in feeding young by other females in her group. Nests are rough bowls of twigs, lined with finer fiber and placed in the upper forks of trees at 10–50 ft (3–15 m) above the ground. In near-treeless areas, Australian magpies will construct nests with wire and place them on the spars of electricity poles. Eggs, in clutches of three to five, are 1.45–1.53 × 1.02–1.10 in (37–39 × 26–28 mm) and pale green to grayish blue, spotted and/or streaked in earth reds, reddish browns, umber, and dusky. No one clutch resembles another. Eggs hatch in 20–22 days and young fledge in another 28–30.

conservation status

Not threatened; populations benefit by habitat clearing throughout rural Australia.

significance to humans

A commensal around human habitation.


Pied currawong

Strepera graculina

subfamily

Cracticinae

taxonomy

Corvus graculinus Shaw, 1790, Port Jackson (Sydney), Australia. Three to six subspecies in eastern Australia: one large-billed on eastern Cape York Peninsula (Strepera graculina magnirostris), one all-dusky in western Victoria (S. g. ashbyi), and the others between which vary regionally in size and tone. One further slender-billed subspecies occurs on Lord Howe Island (S. g. crissalis).

other common names

English: Black currawong; French: Grand Réveilleur; German: Dickschnabel-Würgerkrähe; Spanish: Currawong Pálido.

physical characteristics

17–20 in (43–50 cm); 10–12.5 oz (280–360 g). Slender, dusky, crow-like birds with hidden white flashes in wings; white tips on long tails; and broad, white bands at base of upper- and undersurface of tail and undertail coverts. Eyes pale yellow and bills and feet black. Females resemble males except for shorter bills; juveniles duller and grayer, with brown eyes and yellow gapes and mouths.

distribution

Coastal and subcoastal eastern mainland Australia between Cape York Peninsula and western Victoria, with outlier on Lord Howe Island.

habitat

Closed forests (including rainforests and wet eucalypt forests) to denser, taller wetter woodlands of euclaypts; also urban gardens and parks where tree cover is ample. Cool montane forests and woodlands of eucalypts are core habitat.

behavior

Skulking, opportunistic, and piratical predators. Territorial during breeding, pied currawongs congregate in loose foraging flocks of up to a hundred or so at other times; southeast populations move out of mountain ranges to lower altitudes and more northerly regions in early autumn (late March to early April) and return in early spring (September) to breed. Foraging flocks work through all strata of their habitat, running over the ground, bounding about foliage, and flying from tree to tree in slow, loping undulations broken by floppy wing beats. They call constantly to maintain contact or advertise territory with loud whining whistles and clanking glottal chortles. They do not sing or carol like other Australian magpie-shrikes but do call loudly to one another when gathering to roost in tall trees at dusk.

feeding ecology and diet

Omnivorous scavengers that search for food anywhere, bounding about shrubbery and branches; poking into foliage and crevices; or walking, running, and hopping over the ground to peck, probe, and jab. Rubbish tips and camping grounds with food waste are favored. Carrion, small birds, nestlings, insects, caterpillars, lizards, snails, food scraps, and berries are all eaten. Over the last 20–30 years, berry-bearing ornamental trees have attracted currawongs to many urban habitats on the east Australian coast, where the birds remain year-round and cause havoc among other bird species during breeding.

reproductive biology

Strictly monogamous and territorial. Pairs establish territory of some 12–37 acres (5–15 ha) early in spring (September, or as early as July in the far north) and build from late September to mid-October, so that young fledge from mid-November into December; only one brood reared per year. Although males may assist in gathering nest material and in feeding older young, females bear the brunt of nest construction, incubation, and the brooding and feeding of young. Nests are rough and rather flimsy bowls of twigs, lined with finer fiber and placed high in the outer branchlets of tall trees at about 40–65 ft (12–20 m) above the ground. Eggs, two or usually three per clutch, are 1.58–1.69 × 1.10–1.25 in (40–43 × 28–32 mm) and pinkish buff finely specked and spotted with dark brown and dusky. They hatch in 20–22 days, and young fledge in about another 30.

conservation status

Not threatened. Because of their predatorial behavior, pied currawongs pose a serious threat themselves to the nesting of many species of Australian birds in human-modified areas.

significance to humans

None known.


Resources

Books

Amadon, D. "Cracticidae." In Check-List of Birds of the World. Vol. 15. Cambridge, Mass.: Museum of Comparative Zoology, 1962.

Coates, B.J. The Birds of Papua New Guinea. Vol. 2. Alderley, Qld: Dove Publications, 1990.

MacKinnon, J., and K. Phillipps. A Field Guide to the Birds of Borneo, Sumatra, Java, and Bali. Oxford: Oxford University Press, 1993.

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

Schodde, R., and I.J. Mason. The Directory of Australian Birds, Passerines. Melbourne: CSIRO Publishing, 1999.

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

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

Smythies, B.E. The Birds of Borneo. 3rd edition. Kota Kinabalu and Kuala Lumpur: The Sabah Society and the Sabah Nature Society, 1981.

Periodicals

Amadon, D. "Taxonomic Notes on the Australian Butcherbirds (Family Cracicidae)." American Museum Novitates 1504 (1951): 1–33.

Sibley, C.G. and J.E. Ahlquist. "The Relationships of the Papuan Genus Peltops." Emu 84 (1984): 181–183.

Organizations

Australian National Wildlife Collection. GPO Box 284, Canberra, ACT 2601 Australia. Phone: +61 2 6242 1600. Fax: +61-2-6242-1688. E-mail: Richard [email protected]

Other

Australian Biological Resources Study. Canberra, ACT, Australia.

UNEP World Conservation Monitoring Center. Threatened Animals of the World. <http://www.unep-wcmc.org/species/animals/animalredlist.html> (January 2002).

Richard Schodde, PhD