Mudnest Builders: Grallinidae

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MUDNEST BUILDERS: Grallinidae

AUSTRALIAN MAGPIE-LARK (Grallina cyanoleuca): SPECIES ACCOUNT

PHYSICAL CHARACTERISTICS

Members of the Grallinidae family are various colorations of black, white, gray, and brown. The average length of an adult is 8 to 18 inches (20 to 45 centimeters).


GEOGRAPHIC RANGE

Mudnest builders are found in Australia, New Guinea, Timor, and Lord Howe Island.


HABITAT

All but one species of Grallinidae dwell in open space with trees for nesting. The torrent-lark prefers wooded areas near rivers and streams, where it forages for food.


DIET

Mudnest builders eat insects and other invertebrates, animals without a backbone, such as snails and worms. The apostlebird also feeds on seeds.


BEHAVIOR AND REPRODUCTION

Members of the Grallinidae family are monogamous (muh-NAH-guh-mus), and the majority pair with a single mate for their lifespan. Both males and females feed their offspring, and in some species, other group members (usually juveniles) will also feed nestlings.

While paired Australian magpie-larks like to travel with their mates, both apostlebirds and white-winged choughs (CHUFFS) prefer to flock in small groups of up to twenty birds.

MUDNEST BUILDERS AND PEOPLE

Mudnest builders and humans coexist peacefully.

DEFENSIVE DUETS

Pairs of male and female Australian magpie-larks defend their nest and territory with a song and wing display known as an antiphonal (an-TIFF-uh-nul) duet. They perch out in the open together, and alternate their distinctive "pee-wee" call. While one calls and the other answers, they both raise their wings high in a display of power to show would-be intruders who's in charge.

CONSERVATION STATUS

None of the Grallinidae species are currently endangered.

AUSTRALIAN MAGPIE-LARK (Grallina cyanoleuca): SPECIES ACCOUNT

Physical characteristics: The Australian magpie-lark has a black and white body. The male has a black back, chest, and face, with a white stripe above the eye. The female's face is all white. Both have white markings on their predominantly black wings. The birds' legs are exceptionally long, and adults have white eyes and beaks. Juveniles of the species have plumage coloring similar to adults, but their eyes and bills are white. Adult magpie-larks are 10 to 12 inches (25 to 30 centimeters) in length and weigh an average of 3 to 4 ounces (80 to 115 grams).

Geographic range: The Australian magpie-lark is found throughout Australia (except in desert areas) and in southern New Guinea, Timor, and Lord Howe Island.


Habitat: Australian magpie-larks are highly adaptable birds, and make their home in a wide variety of habitats both near and far from people, including urban, agricultural, and residential areas. When they dwell in forests, it is usually near the edge or in a clearing where there is open space to forage. They choose nest-building locations where there is access to water and therefore mud.


Diet: Magpie-larks forage at ground level for insects, insect larvae, earthworms, and freshwater snails. They will also eat at backyard feeders.


Behavior and reproduction: Like other members of the family, the Australian magpie-lark builds a cup-shaped mud nest lined with soft grasses and feathers. Male and female magpie-larks are monogamous, and usually stay together throughout their lifespan, breeding each season as a pair. If a male leaves a female after mating for any reason, the female will abandon the nest.

Australian magpie-larks are biparental, meaning that both male and female take part in nest building, egg incubation, and in feeding their nestlings. The female lays a clutch of three to five oval-shaped white-to-pink eggs speckled with brown.

Studies of Australian magpie-lark breeding behavior have found that those pairs of birds who have bred together successfully in previous seasons will raise more fledglings in subsequent seasons than other newly-mated pairs. Researchers attribute this to the fact that established magpie-lark "couples" start breeding earlier in the season, allowing them to fledge multiple broods.

Magpie-larks aggressively defend their nest and surrounding territory, and have been known to attack other birds, animals, humans, and even images of themselves in mirrors or other reflective surfaces when they felt their nest was threatened. Human attacks are rare.

Incubation of eggs takes up to eighteen days, and the young birds fledge about three weeks after hatching. Young birds, and those adults who aren't paired with a mate, travel in large flocks that move northward in fall and winter and south in spring and summer.


Australian magpie-larks and people: The Australian magpie-lark, called the peewee by many Australians because of their "pee-o-wit" call, are not considered agricultural or residential pests. In agricultural areas their presence is often encouraged, as they feed on disease-carrying freshwater snails that can infect sheep and cattle.


Conservation status: Australian magpie-larks are plentiful and not considered threatened. ∎


FOR MORE INFORMATION

Books:

Simpson, Ken, Nicolas Day, and Peter Trusler. Birds of Australia Princeton, NJ: Princeton University Press, 2000.

Simpson, Ken, and Nicolas Day. Field Guide to the Birds of Australia, 4th ed. Ringwood, Australia: Viking O'Neil, 1993.

Periodicals:

Davidson, Steve. "For These Birds, Fidelity's a Lark." Ecos (April–June 2000): 36.


Web sites:

"Magpie-Lark." Australian Museum. http://www.amonline.net.au/factsheets/magpie_lark.htm (accessed on June 14, 2004).

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