Upland goose
| Upland goose | |
|---|---|
 | |
| Female (left) and male (right) in Argentina | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Anseriformes |
| Family: | Anatidae |
| Subfamily: | Tadorninae |
| Genus: | Chloephaga |
| Species: | C. picta |
| Binomial name | |
| Chloephaga picta (Gmelin, 1789) | |
| Subspecies | |
| |
| Synonyms | |
|
Foetopterus ambiguus | |
The upland goose or Magellan Goose (Chloephaga picta) is a sheldgoose of the shelduck-sheldgoose subfamily of the Anatidae, the biological family that includes the ducks and most duck-like waterfowl such as the geese and swans. This bird is indigenous to the southern part of South America.[1]
Description
These birds are 60–72.5 centimetres (23.6–28.5 in) long and weigh 2.7–3.2 kilograms (6.0–7.1 lb).[2] Males have a white head and breast, whereas the females are brown with black-striped wings and yellow feet, and could be mistaken for ruddy-headed geese. A greenish-bronze speculum is located on the inner secondary flight feathers of the adult male.[3]
In Chapter VI of On the Origin of Species, author Charles Darwin noted that the upland goose has webbing between its toes that appeared to be "rudimentary in function, though not in structure", and concluded that this was a vestigial anatomical feature in this bird.[4]
Distribution and habitat
They are found in southern temperate grasslands, arid lowland scrubs, pastures and agricultural lands, from sea level up to around 1,500 meters.[3] There is also a sizeable introduced population on the sub-Antarctic South Georgia Island.[5]
Behaviour and Diet
The Upland Goose is primarily a herbivore, feeding mostly of seeds, leaves, stems, and other plant matter. They are very gregarious, and flocks of thousands of birds can be found grazing in one pasture alone. They are considered pests by farmers due to the fact that they eat on the pastures that are meant for cattle and sheep. They breed in densely-vegetated areas on plains or slopes, mostly in September and October, or November on the Falkland Islands. Males attract females through a courtship display in which they whistle loudly, to which the female responds with softer cackles. They are monogamous, and if a male encroaches on another's territory, a violent fight may break out. Males have been found injured or dead after these fights.[6]
The nest is on the ground, concealed by dense vegetation, often located near water. A clutch consists of 5-8 eggs which are incubated for about 1 month. When the chicks hatch, they are covered in greyish-brown down. They don't remain in the nest for more than a day, quickly going to a nearby water source or feeding area, and are able to feed themselves from birth. They fledge in 9–10 weeks and reach maturity in 3 years.[6]
References
- 1 2 BirdLife International (2012). "Chloephaga picta". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- ↑ Wildlife Information Network (2013). "Chloephaga picta - Upland goose". Wildpro - the electronic encyclopaedia and library for wildlife. Wildlife Information Network. Retrieved 2013-02-17.
- 1 2 Stang, D (2012). "Chloephaga picta (Magellan/Upland Goose)". ZipcodeZoo. Potomac Maryland: ZipcodeZoo.com. Retrieved 2013-02-17.
- ↑ Darwin, C (1859). "Difficulties on theory". On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life (Full image view 1st ed.). London: John Murray. pp. 171–206.
- ↑ A Field Guide to the Wildlife of South Georgia; Princeton University Press 2012
- 1 2 "Upland Goose". oiseaux-birds. Retrieved January 14, 2016.