Artamus cyanopterus

Physical characteristics: Dusky woodswallows are medium-sized, swallow-like birds that have a smoky blue to smoky brown body; small patch of black in the front of the eyes; dark gray to blackish wings with a white leading edge; dark gray to blackish tail with distinctive white spots at the end; and silvery underwings. The bill is short and pale blue with a black tip. Adults are 6.7 to 7.1 inches (17 to 18 centimeters) long and weigh between 1.1 and 1.6 ounces (31 and 46 grams).

Geographic range: Dusky woodswallows are found in Australia, specifically the eastern and southern portions of the country. They migrate northward for the winter.

SPECIES ACCOUNT

Habitat: Dusky woodswallows inhabit open eucalyptus (yoo-kah-LIP-tus) forests (those consisting of tall, aromatic trees) and woodlands, along water courses, and over natural clearings. They especially like rural areas and wet climates.

Diet: Their diet consists of insects, foliage, and nectar. They usually catch flying insects, but will also take prey off the ground.

Behavior and reproduction: Dusky woodswallows are often found in small communal flocks of ten to thirty birds. They are social birds, often roosting in a tight group within a tree hollow or fork. Dusky woodswallows rest during the day, usually perching closely together as a group. They communicate with each other with a chattering call, and will display anxiety when predators or intruders are close by giving out a harsh mobbing call.

Males and females build a small, flimsy, cup-like nest made of plant fibers. The nest, made from August to January, is constructed within a colony of other dusky woodswallows, often within a tree trunk or other similar structure. A small territory surrounding the nest is defended by the mated pair. Parents may use helpers to take care of their young. Females lay three to four blotched white eggs. The incubation period is around sixteen days. The fledgling period is sixteen to twenty days.

Dusky woodswallows and people: There is no known significance between people and dusky woodswallows.

Conservation status: Dusky woodswallows are not considered to be threatened. ■

FOR MORE INFORMATION Books:

del Hoyo, Josep, A. Elliott, J. Sargatal, J. Cabot, et al., eds. Handbook of the Birds of the World. Barcelona: Lynx Edicions, 1992.

Dickinson, Edward C., ed. The Howard and Moore Complete Checklist of the Birds of the World, 3rd ed. Princeton, NJ and Oxford, U.K.: Princeton University Press, 2003.

Forshaw, Joseph, ed. Encyclopedia of Birds, 2nd ed. San Diego, CA: Academic Press, 1998.

Harrison, Colin James Oliver. Birds of the World. London and New York: Dorling Kindersley, 1993.

Perrins, Christopher M., and Alex L. A. Middleton, eds. The Encyclopedia of Birds. New York: Facts on File, 1985.

MAGPIE-SHRIKES Cracticidae

Class: Aves Order: Passeriformes Family: Cracticidae Number of species: 14 species

CHAPTER

phylum class subclass order monotypic order suborder family

PHYSICAL CHARACTERISTICS

Magpie-shrikes are members of the family Cracticidae, which is divided into five groups: peltopses, bristleheads, currawongs, Australian magpies, and butcherbirds. All are black-and-white or blackish birds with strong black feet and booted or scaled legs. The bill is straight, strong, has a tip ranging from hooked and notched to pick-shaped, lacks bristles, is swollen at the upper jaw base, and has nostrils that are deep within bony slits.

Peltopses have a black body with large white patches on face and back; a black bill; a red rump, lower belly, and undertail; and a long tail. Bristleheads have a red head, a black bill, and a dusky-gray short tail. Currawongs are big but slender birds with a black bill, bright yellow eyes, dark gray to blackish plumage (feathers) with white patches in the wings, a long, white-tipped tail, and rounded wings. Australian magpies have black-and-white plumage; black-and-white upperparts, black underparts, pointed wings, short tail, and long legs. Butcherbirds may be all-black to black-hooded with white patches, or all-white with black, gray, and white patterning. These birds have a two-colored bill with a blackish tip and whitish or pale bluish gray base.

Juveniles have similar plumage to adults, although duller and grayer. Fledglings (young birds with recently grown flight feathers), depending on species, may be rusty-brown, washed olive-yellow, or lack clear head patterns. Adults are 6.5 to 22 inches (17 to 55 centimeters) long and weigh between 1.1 and 17.6 ounces (30 and 500 grams).

GEOGRAPHIC RANGE

Magpie-shrikes are found in Australia and New Guinea, along with one species in Borneo.

HABITAT

Magpie-shrikes inhabit wooded regions that include rainforests, savannas (grasslands), and pastures with trees. Pel-topses live on the edge of canopies (uppermost vegetation layer of forest) in both mature and re-growth rainforests; bristleheads occupy the mid-strata of mature, lowland alluvial (river and lake systems) and swamp rainforests; currawongs range from dense, tall, wet forests to open, low, eucalyptus-dominated (yoo-kah-LIP-tus; tall, aromatic tree) woodlands; Australian magpies occupy open habitats such as savannas and pastures; and butcherbirds live in the middle and upper strata of forests and woodlands.

DIET

Their diet consists of various small vertebrates and invertebrates (animals with backbones and without backbones), such as insects, grubs, and worms. Magpie-shrikes also eat eggs, nestlings (young birds unable to leave the nest), and berries.

BEHAVIOR AND REPRODUCTION

All five groups make loud flutings, gargles, and bell-like whistles, except for peltopses that make "tick" or "tinckle" sounds. Magpie-shrikes roost in medium-height tree foliage. Australian magpies sing together in groups, and currawongs call out and answer back while in flocks. Australian magpies and currawongs roost in loose groups.

Butcherbirds, bristleheads, and peltopses live in trees, perching for long time periods while looking for prey, and fly rapidly and directly between trees. They pounce on prey, coming to the ground only to catch food. These birds remain in one large foraging territory throughout the year and are solitary birds, rarely gathering in groups larger than families. Australian magpies feed mostly from the ground. They are social birds with complex social organizations that include senior pairs or small breeding groups in permanent desirable territories, while larger groups of juveniles and other non-breeders live in less desirable territories. Australian magpies walk quietly on the ground and fly swiftly and directly. Currawongs are sometimes social throughout the year in some species, but in other species only gather in large wandering groups when not breeding. They live in all forest levels, fly in easy, wavy movements, and hop and run on the ground.

Breeding for all groups occurs irregularly throughout the year in tropical areas but only from early spring to summer (August to January) in temperate and subtropical regions. More than one brood (young birds born and raised together) can be raised in a year, but usually only one. Most species are monogamous (muh-NAH-guh-mus; having one mate), except for the polygynous (puh-LIJ-uh-nus; having several mates) Australian magpies. They are territorial birds. Only females build nests, which are rough cups of twigs and rootlets lined with finer fibers. The female does all of the incubating (sitting on eggs) while the male takes care of his nesting mate. Clutches (eggs hatched together) are one to five eggs that are cream or pinkish buff to pale green, lined or spotted with red-browns and gray-blacks.

MAGPIE-SHRIKES AND PEOPLE

There is little significance between people and magpie-shrikes other than with Australian magpies, which are known for their aggressiveness and caroling songs.

CONSERVATION STATUS

One species of magpie-shrike, the Bornean bristlehead, is listed as Near Threatened, in danger of becoming threatened with extinction.

Bornean Bristlehead
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