Magpie-Shrikes: Cracticidae

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MAGPIE-SHRIKES: Cracticidae

BORNEAN BRISTLEHEAD (Pityriasis gymnocephala): SPECIES ACCOUNTS
GRAY BUTCHERBIRD (Cracticus torquatus): SPECIES ACCOUNTS

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. Peltopses 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 (Pityriasis gymnocephala): SPECIES ACCOUNTS

Physical characteristics: Bornean bristleheads are thick-bodied, dusky to mostly black colored birds. They have a massively hooked bill; a red, mostly bare head with a patch of orange-yellow stubble (small projection-like bare feather shafts that give its name "bristlehead") on the crown; an edge of scarlet feathering on upper back and breast; a lower breast covered in bristle-like brown and red feathers; a very short tail; and black wings, tail, and bill. Females have chestnut eyes, a red patch on the flanks, and yellow feet. Adults are 10 to 11 inches (26 to 28 centimeters) long.


Geographic range: They are found in Borneo, except for its north-central areas, at elevations below 3,900 feet (1,200 meters).

Habitat: Bornean bristleheads are found in lowland swamps and rainforests.


Diet: Their diet consists primarily of large insects such as arboreal (living in trees) beetles, grasshoppers, cockroaches, bugs, and larvae (LAR-vee). They take prey mostly from branches and trunks in the middle parts of forests, but will also go to recently cleared areas to find exposed food. Small olive- to plum-sized fruits are occasionally eaten.


Behavior and reproduction: Bornean bristleheads forage through the forest's mid-strata in noisy groups of about six to ten birds. They are very active while foraging, moving with sideward hops while calling loudly, and bending and looking closely for prey. They make direct flights on fast, shallow wings and make noisy calls of whines, honks, and chortles to maintain contacts, which often turn into loud, mixed choruses of various calls.


Bornean bristleheads and people: There is no known significance between people and Bornean bristleheads.


Conservation status: Bornean bristleheads are listed as Near Threatened because of deforestation. ∎

GRAY BUTCHERBIRD (Cracticus torquatus): SPECIES ACCOUNTS

Physical characteristics: Gray butcherbirds are medium-sized, bull-headed birds with a tapered body; patterned plumage of blacks, grays, and whites; black head with white spot (between eyes and upper bill) and collar; dark brown eyes; gray-and-black bill; gray back; white rump; black tail (with white tips) and wings (with white stripes); grayish white underparts; and dark gray legs and feet. Females are smaller than males, generally have more gray on their breast, and have a shorter bill. Juveniles look like adults but have a dull-gray bill without a hook, are patterned with dusky-olive and speckled upperparts, and have buff to yellowish underparts. Adults are 10 to 12 inches (25 to 30 centimeters) long and weigh between 2.8 and 4 ounces (80 and 110 grams).

Geographic range: Gray butcherbirds are found in much of southern and inland Australia from mid-eastern Queensland through southern Australia to northern Western Australia. They are also found in the northernmost parts of the Northern Territory, and in Tasmania.


Habitat: Gray butcherbirds inhabit closed woodlands and open forests of eucalyptus and acacias (uh-KAY-shuhz; flowering trees). They are not found in treeless deserts.


Diet: Their diet consists of mostly insects but also small birds, nestlings, reptiles (such as lizards), mice, fruits, and seeds. They sit on open perches at 6.5 to 40 feet (2 to 12 meters) while searching for prey. Once sighted, they aggressively pounce, mostly from the ground but sometimes while in flight. Feeding is done alone, in pairs, or in small family groups.

Behavior and reproduction: Monogamous mating pairs defend the same breeding territory (20 to 99 acres, or 8 to 40 hectares) all year-round, but have a larger home range. The pair sings back-and-forth with songs of fluted whistles and ringing caws, which are also heard when alarmed or to show aggression. Gray butcherbirds breed from July to August and December to January. They construct (in about four weeks) tight, bowl-shaped nests that are made with sticks and twigs and lined with grasses and other soft fibers. Nests are usually located about 33 feet (10 meters) or less from the ground, within upright forks in outer foliage. Females lay three to five brownish green eggs that are spotted in red-browns and are incubated by the female while the male defends the area. The incubation period (time to sit on eggs before hatching) is twenty-two to twenty-five days. The young are fed by both parents and leave the nest after about twenty-eight days, but remain in the breeding territory for about one year to help parents raise future broods.


Gray butcherbirds and people: Gray butcherbirds feed on food scraps thrown out by people.

Conservation status: Gray butcherbirds are not considered to be threatened. However, many populations are declining because of habitat clearance. ∎


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.