| Magpie goose | |
|---|---|
 | |
| NearEast Point, Northern Territory | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Anseriformes |
| Family: | Anseranatidae |
| Genus: | Anseranas Lesson, 1828 |
| Species: | A. semipalmata |
| Binomial name | |
| Anseranas semipalmata (Latham, 1798) | |
| Synonyms | |
Anas semipalmataLatham, 1798 | |
Themagpie goose (Anseranas semipalmata) is the sole living representativespecies of thefamilyAnseranatidae. This commonwaterbird is found in northernAustralia and southernNew Guinea.[2] As the species is prone to wandering, especially when not breeding, it is sometimes recorded outside its core range.[2] The species was once also widespread in southern Australia but disappeared from there largely due to the drainage of the wetlands where the birds once bred. Due to their importance to Aboriginal people as a seasonal food source,[3] as subjects of recreational hunting,[4] and as a tourist attraction, their expansive and stable presence in northern Australia has been "ensured [by] protective management".[5]
Magpie geese are unmistakable birds with their black and white plumage and yellowish legs. The feet are only partially webbed, and the magpie goose feeds on vegetable matter in the water, as well as on land. Males are larger than females. Unlike truegeese, theirmolt is gradual, so no flightless periods result. Their voice is a loud honking.
This species is placed in theorderAnseriformes, having the characteristic bill structure, but is considered to be distinct from the other species in thistaxon. The related and extant families,Anhimidae (screamers) andAnatidae (ducks,geese, andswans), contain all the other taxa. The magpie goose is contained in the genusAnseranas and family Anseranatidae, which aremonotypic now.[6]
A cladistic study of the morphology of waterfowl found that the magpie goose was an early and distinctive offshoot, diverging after screamers and before all other ducks, geese, and swans.[7]
This family is quite old, aliving fossil, having apparently diverged before theCretaceous–Paleogene extinction event — the relativeVegavis iaai lived some 68-67 million years ago. Thefossil record is limited, nonetheless. The enigmatic genusAnatalavis (HornerstownLate Cretaceous orEarly Paleocene of New Jersey, USA -London ClayEarly Eocene ofWalton-on-the-Naze, England) is sometimes considered to be the earliest known. OtherPaleogene birds sometimes considered magpie-geese are the generaGeranopsis from theHordwell FormationLate Eocene to theEarly Oligocene of England andAnserpica from theLate Oligocene ofBilly-Créchy (France).[8]
The earliest known member of the group in Australia isEoanseranas represented by fossils found in the late Oligocene Carl Creek Limestone of Queensland.[9] Additional fossils from North America and Europe suggest that the family was spread across the globe during the late Paleogene period.[10] The Australian distribution of the living species ties in well with the presumedGondwanan origin ofAnseriformes, but Northern Hemisphere fossils are puzzling. Perhaps the magpie geese were one of the dominant groups of Paleogene waterfowl, only to become largely extinct later.[original research?]
The magpie goose is found in a variety of openwetland areas such asfloodplains andswamps, where they wade and swim. They eat mostly vegetation such as dry grass blades, grass seeds,spike rush bulbs andwild rice.[11]
Magpie geese are fairly sedentary apart from some movement during the dry season. They are colonial breeders and are gregarious outside of the breeding season when they can form large and noisy flocks of up to a few thousand individuals. Magpie geese nest on the ground or in trees where they can be five meters or higher above the ground. Their typicalclutch is between 5-14 eggs. Some males mate with two females, all of which raise the young, unlike some other polygamous birds.[12] This may be beneficial whenpredation of young is high as chicks raised by trios are more likely to survive.
This species is plentiful across its range, although this is significantly reduced in comparison to the range at time of European settlement. The range once extended as far south as theCoorong and the wetlands of the southeast ofSouth Australia and WesternVictoria. For Australia as a whole, it is not threatened and has a controlled hunting season when numbers are large. However, most of the southern populations were extirpated in the mid-20th century byoverhunting andhabitat destruction. The species has been subject toreintroduction projects such asBool Lagoon between Penola and Naracoorte. Populations in more northern areas have again reached a level where it can be regularly utilized by hunters, although not in the example provided. The magpie goose was listed asnear threatened on the 2007 advisory list of threatened vertebrate fauna in Victoria.[13] In the December 2007Flora and Fauna Guarantee Act list of threatened fauna, it is also listed.[14][15] As of early 2008, an Action Statement for the recovery and future management of this species had not been prepared.[16]
With the advent of climate change, and more frequent seawater inundations of the current extensive freshwater floodplains,CSIRO scientists argue that magpie geese populations may be at risk.[17]
TheKunwinjku of westernArnhem Land know this bird asmanimunak.[18] It became an important food item with the formation of wetlands about 1500 ya, and is depicted in rock art from this period.Mimi figures are often shown holding goose-feather fans.[19] InYolŋu Matha the bird is known asgurrumaṯtji,[20] or aroundRamingining asgumang.[21]
In theWadawurrung language, the magpie goose is known as Ngangok.
_immature_Fogg_Dam.jpg)
_in_flight_Kakadu.jpg)
