Struthidea cinereaapostlebird

Geographic Range

Apostlebirds (Struthidea cinerea) are found in eastern Australia, on the western side of the Great Dividing Range. They occur only on the mainland and are non-migratory. ("Magpie-Larks and Australian Mudnesters", 1967)

Habitat

Preferred apostlebird habitat is generally grassland and open eucalyptus woodlands. They require a nearby water source, such as a stream, in order to obtain mud for nest building. (Blakers, et al., 1984)

Physical Description

Apostlebirds are 29 to 47 cm in length, and weigh 110 to 130 g. Their plumage is soft and dark gray with paler gray streaks, their wings are brown, and their tails are black. They have stout bills. Males and females are sexually monomorphic in plumage and size. Iris color varies with age; fledglings have brown eyes, yearlings have gray eyes, and adults (at least 2 years old) have gray eyes with a thin yellow outer ring. This ring becomes more apparent as the birds age. ("Magpie-Larks and Australian Mudnesters", 1967; "Apostlebird", 2006; Chapman, 1998; Simpson and Day, 1984; Woxvold, 2004)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    110 to 130 g
    3.88 to 4.58 oz
  • Range length
    29 to 47 cm
    11.42 to 18.50 in

Reproduction

Apostlebirds are cooperative breeders. They form familial social groups of up to 20 members, consisting of a dominant male, several females, and juveniles from previous seasons. These immature members stay to help with parental duties. During the breeding season, the groups occupy distinct, well-defended territories.

Before breeding, apostlebirds engage in a characteristic display. Birds at the nest become excited and give a call. The displaying bird raises its head and neck feathers and bobs up and down in time with the calls. It also fans its tail and raises it up and down. ("Apostlebird", 2006; "Magpie-Larks and Australian Mudnesters", 1967; "Apostlebird", 2006; Chapman, 1998; Woxvold, 2004)

The breeding season is from August to early January. All group members help in parental duties, i.e., building the nest, incubating and brooding the nestlings, and feeding the young. The nest is a cup, about 14 cm in diameter, made of mud and built on a horizontal limb up to 40 feet above the ground. If mud is not available, the birds may use animal dung, including that of emus. If a nest is still in good condition after a previous breeding season, it is sometimes reused. ("Magpie-Larks and Australian Mudnesters", 1967; "Apostlebird", 2006; Chapman, 1998; Hill, 1967; Woxvold, 2004)

A group will sequentially raise up to two successful broods in a single season. Usually only one female will lay in a given nest, but sometimes two females may do so. Two to eight eggs are laid, depending on how many females are laying in the nest. The eggs are a pale bluish white color with black or gray splotches. Incubation takes 18 to 19 days, and the nestling period is 18 to 29 days. Usually only about 4 nestlings survive to fledge. ("Magpie-Larks and Australian Mudnesters", 1967; "Apostlebird", 2006; Chapman, 1998; Hill, 1967; Woxvold, 2004)

  • Breeding interval
    Family groups may raise up to two broods per breeding season.
  • Breeding season
    Breeding occurs from August to early January.
  • Range eggs per season
    2 to 8
  • Range time to hatching
    18 to 19 days
  • Range fledging age
    18 to 29 days

All members of the social group help with parental duties. The young are fed both while in the nest and for several months after they fledge. Young may also remain with their family group for some time. ("Magpie-Larks and Australian Mudnesters", 1967)

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-weaning/fledging
    • provisioning
      • male
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • male
      • female
  • post-independence association with parents

Lifespan/Longevity

There is little available information regarding the lifespan of wild or captive apostlebirds.

Behavior

Apostlebirds are social birds, forming groups of 8 to 18 individuals. Most groups consist of 4 to 11 individuals. They spend most of their time on the ground, where they walk with a strutting gait. If disturbed, group members will fly into the branches of a nearby tree and call harshly. ("Every Australian Bird Illustrated", 1975; Blakers, et al., 1984; Chapman, 1998; Hill, 1967)

Apostlebirds are known to bathe in water during the summer when they go to drink. They also engage in anting to control ectoparasites such as lice, and they commonly eat the ants when finished. Another method of pest control is allopreening, several birds will often sit together and preen each other. ("Every Australian Bird Illustrated", 1975; Blakers, et al., 1984; Chapman, 1998; Hill, 1967)

  • Average territory size
    250000 m^2

Home Range

Apostlebird home ranges have not been reported.

Communication and Perception

Apostlebirds give contact calls that consist of piping whistles. Their alarm call is mainly harsh screeches and chattering, sounding like a scratchy 'ch-kew, ch-kew' with a nasal 'git-out.' ("Magpie-Larks and Australian Mudnesters", 1967; "Apostlebird", 2006; Simpson and Day, 1984)

Food Habits

Apostlebirds forage on the ground, eating mainly insects and seeds. The insects they consume include grasshoppers, weevils, shield-bugs, and ants. They are opportunistic, eating insects during the summer and seeds during the winter. They will even catch and eat house mice (Mus musculus) if they have the opportunity. They steady their food by standing on it. ("Every Australian Bird Illustrated", 1975; "Magpie-Larks and Australian Mudnesters", 1967; Blakers, et al., 1984; Chapman, 1998; Hill, 1967)

During the non-breeding season, aggregations of up to 50 birds gather at a common food source. While they do not behave aggressively toward each other at this time, they do not form a cohesive flock, and fly off in separate groups when disturbed. ("Every Australian Bird Illustrated", 1975; "Magpie-Larks and Australian Mudnesters", 1967; Blakers, et al., 1984; Chapman, 1998; Hill, 1967)

  • Animal Foods
  • mammals
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • seeds, grains, and nuts

Predation

Apostlebirds have a harsh, screeching alarm call that they use when they are disturbed. They fly into the nearest tree and protest noisily. Their nests have been known to fail due to predation by brown goshawks (Accipiter fasciatus) and grey butcherbirds (Cracticus torquatus). Newly hatched young can also be overtaken by meat ants (Iridomyrmex purpureus). ("Every Australian Bird Illustrated", 1975; Hill, 1967; Woxvold, 2004)

Ecosystem Roles

There is little available information about the ecosystem roles of apostlebirds. They act as predators and are prey for their predators.

Economic Importance for Humans: Positive

Little is known about benefits apostlebirds provide to humans.

Economic Importance for Humans: Negative

Due to their habit of digging in soil and leaf litter as they forage, apostlebirds may be a nuisance to some humans, such as gardeners. Otherwise, there are no known adverse effects of apostlebirds on humans. ("Magpie-Larks and Australian Mudnesters", 1967)

  • Negative Impacts
  • crop pest

Conservation Status

Apostlebirds are considered a species of least concern by the IUCN Red List of Threatened Species.

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Laura Mateskon (author), Michigan State University, Pamela Rasmussen (editor, instructor), Michigan State University.

Glossary

Australian

Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

cooperative breeder

helpers provide assistance in raising young that are not their own

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

insectivore

An animal that eats mainly insects or spiders.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynous

having more than one female as a mate at one time

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

1975. Every Australian Bird Illustrated. London: Hale.

Australian Museum. 2006. "Apostlebird" (On-line). Birds in Backyards. Accessed December 05, 2006 at http://birdsinbackyards.net/finder/display.cfm?id=133.

1967. Magpie-Larks and Australian Mudnesters. Pp. 493 in Firefly Encycopledia of Birds, Vol. 1, 1 Edition. Toronto: Firefly Books Ltd..

Blakers, M., S. Davies, P. Reilly. 1984. The Atlas of Australian Birds. Victoria: Melbourne University Press.

Chapman, G. 1998. The Social Life of the Apostlebird Struthidea cinerea. Emu, 98: 178-183.

Hill, R. 1967. Australian Birds. Melbourne, Australia: Thomas Nelson (Australia) Ltd..

Simpson, K., N. Day. 1984. The Birds of Australia. Dover, NH: Tanager Books.

Woxvold, I. 2004. Breeding ecology and group dynamics of the apostlebird. Australian Journal of Zoology, 52: 561-581.