MAGPIE-GOOSE  Anseranatidae
The Magpie-Goose is found only in swamps and wet grasslands of southern New Guinea and northern Australia. In this respect it fills a niche rather like the one inhabited by screamers [Anhimidae] in the New World. Madge & Burn (1988) summarize: "A unique 'goose' ... that exhibits many features linking the true wildfowl with the terrestrial screamers of South America, the latter resembling gamebirds rather than waterfowl. The long hind toe, slightly-webbed feet, gradual molt progression (thus lacking a flightless period), greatly elongated trachea (in both sexes) and family trios (one male, two female) are all features that isolate this strange bird." As shown in John Marchant's photo (above), Magpie-Geese may occur in large flocks in prime habitat. They superficially recall Spur-winged Goose Plectropterus gambensis of Africa, but only in the pied plumage (Magpie-Goose has a white back, Spur-winged does not) and the protuberance on top the bill. Bill knobs tend to be larger in males than in females.
Splitting the Magpie-Goose as a separate family is an innovation, based on genetic distance, begun by Sibley & Ahlquist (1990) and Sibley & Monroe (1990). However, those authors also placed the whistling-ducks in a separate family ['Dendrocygnidae"]. The new Howard & Moore checklist (Dickinson 2003), in which family-level decisions were made by Joel Cracraft, elevates Magpie-Goose to family level while the whistling-ducks remain a subfamily [Dendrocygninae] of the large ducks, geese, and swans family [Anatidae]. I follow suit here because I'm including all the Dickinson (2003) families.
In Australia, family groups and flocks of Magpie-Geese move from swamp to wetlands depending on water levels in the dry and wet seasons. Pairs or trios build floating platforms of spike-rush for nests as the swamps fill in the wet season. In typical situations, two females share a nest with one male, each female laying 6-9 eggs. Often they stand over the eggs to shade them from the tropical sun rather than incubating. Youngsters are flightless until 11 weeks of age, and they remain with the parents until the following wet season (Frith 1979, Blakers et al. 1984).
Photos: The flock of Magpie-Geese Anserianas semipalmata was photographed by John Marchant in Hastie Swamp, Queensland, Australia, on 8 Nov 1982. Photo © John Marchant, used with permission, all rights reserved.

Bibliographic note

There is no family book but this group is covered in standard waterfowl texts, and the Australian literature that includes this family is reasonably extensive.

Literature cited:

Blakers, M., S.J.J.F. Davies, and P.N. Reilly. 1984. The Atlas of Australian Birds. Royal Australian Ornith. Union, Melbourne Univ. Press, Carlton, Victoria.

Dickinson, E.C., ed. 2003. The Howard & Moore Complete Checklist of the Birds of the World. 3d ed. Princeton Univ. Press, Princeton, N.J.

Frith, H.J., consulting ed. 1979. The Reader's Digest Complete Book of Australian Birds. 2d revised ed. Reader's Digest Services, Ltd., Sydney.

Madge, S., and H. Burn. 1988. Waterfowl: an Identification Guide to the Ducks, Geese, and Swans of the World Houghton Mifflin, Boston.

Sibley, C.G., and J.E. Ahlquist. 1990. Phylogeny and Classification of Birds: A Study in Molecular Evolution. Yale Univ. Press, New Haven, CT.

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




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