Magellangans

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Magellangans
Magellangans, male

Magellangans, male

Systematics
Family : Duck birds (Anatidae)
Subfamily : Half geese (Tadorninae)
Tribe : True half-geese (Tadornini)
Genre : Mirror geese ( Chloephaga )
Type : Magellangans
Scientific name
Chloephaga picta
( Gmelin , 1789)
Magellangans, female
Magellanic couple on the coast
chick
A flock of Magellan Geese in Santa Cruz, Argentina
Chloephaga picta

The Magellangan ( Chloephaga picta ) is a bird and belongs to the duck family . The sexual dimorphism is similar in belonging to the same genus as kelp goose pronounced in favor of a Halbgansart: females have a brown plumage, while the body plumage of Ganter white and gray.

To the half geese counting Upland Goose is the most common Halbgansart South America. Their population in the Falkland Islands alone is more than 200,000 individuals. The population on the South American continent is estimated to be more than 1 million birds, but the population is declining overall. Sheep have become its main food competitor.

There are occurrences in Central Europe, but these can only be traced back to park and aviary birds. One or two breeding pairs have been recorded for the Netherlands. The first broods occurred in Belgium in 1993, and since then their numbers have increased to thirty to forty breeding pairs in Flanders alone . There are still no reliable evidence of breeding for Germany.

Occurrence

Their breeding areas are in the large grasslands in the south of South America . On the coasts of Tierra del Fuego , Chile , Patagonia or on the Falkland Islands , the Magellangans often live in pairs near waters, which they rarely visit. Around March it migrates in large swarms to the northern areas, only a small part remains in the breeding areas. A distinction is made between two subspecies , in addition to the nominate form, Chloephaga picta leucoptera . The latter subspecies is usually referred to in German as the Great Magellan . The nominate form Chloephaga picta picta is called the Little Magellan .

features

The Magellan goose is a large species of half-goose. It reaches a body length of 60 to 65 centimeters. The Magellangans weighs on average more than 3.1 kilograms.

The male has a white head, chest and belly plumage, the rest of the plumage is gray. The female has a brown-gray plumage. In terms of plumage color, the female Magellangan resembles the red-headed goose ( Chloephaga rubidiceps ). Another differentiator is the feet. In the female they are orange to yellow, in the male dark gray to black. The beaks are black in color in both sexes.

Reproduction

Magellan geese form pair bonds for several years. The individual breeding pairs relate to small, but strictly separated breeding areas near the water. They build their nests in self-scratched hollows under bushes, in tall grass or simply without any cover on dry ground. They pad the nest with plant fibers and down. The clutch consists of five to eight eggs, which are hatched in a period of 30 to 32 days. Both adult birds take part in the brood care. During this time, the two parent birds also go through the rocking moult, so that they are unable to fly.

Magellan and human

Magellangans as hunting prey and food competitor for domestic animals

The Magellangans are often hunted, as they are classified as grazing animals as a major competitor for feed for domestic sheep . Magellan geese are also considered tasty. In the Falkland Islands, for example, young birds and also full-grown Magellan geese, which have fed on berries for a long time in the autumn, are particularly valued. As early as 1690, when the British first reached the Falkland Islands, they commented on the large number of geese found there. A century later, visitors pointed out that they were so abundant that 150 men within a 15-kilometer radius could hunt enough magellan geese to feed on for two months. As food competitor to domestic sheep, they were classified from the end of the 19th century. In the Falkland Islands, government employees classified Magellan geese as pests in 1905 and awarded prizes for every goose beak brought in. Agricultural experts, who were present in the Falkland Islands in 1969 and 1970 to explore ways of increasing agricultural productivity, also recommended stronger control measures for this species. Research carried out in the late 1970s, however, showed that the geese had only one ate up to five percent of the annual grass growth. However, this study also showed that Magellan geese showed a preference for freshly sown willows. However, the investigators also questioned the point of shooting magellanic and red-headed geese and recommended that the geese be tolerated and that agricultural practices should be changed so that grassland near ponds and in valleys should be rented.

In the Falkland Islands, however, hunting has not yet resulted in a significant decline in the population. The low population density on the Falkland Islands plays a role here. Foxes as the most important predators have been decimated or partly exterminated by the fur hunters in the areas of distribution, so that the Magellangans have multiplied strongly. In addition, there is constant development of new grasslands for livestock farming.

Attitude in Europe

The Greater Magellangans came to Europe before the nominate form. The first breeding succeeded in 1852 at the London Zoo. The small Magellangans, on the other hand, were only kept in the zoo in 1871 and only moved into captivity for the first time in 1901. Since then, Magellan geese have been shown continuously in zoos. Since they only need a bathing opportunity, but do not need a pond for their well-being, they are often kept on ungulate enclosures.

supporting documents

literature

  • Janet Kear (Ed.): Ducks, Geese and Swans. Oxford University Press, 2005, ISBN 0-19-854645-9 .
  • Hartmut Kolbe; Die Entenvögel der Welt , Ulmer Verlag 1999, ISBN 3-8001-7442-1
  • Hadoram Shirihai: A Complete Guide to Antarctic Wildlife - The Birds and Marine Mammals of the Antarctic Continent and Southern Ocean , Alula Press, Degerby 2002, ISBN 951-98947-0-5
  • Robin and Anne Woods: Atlas of Breeding Birds of the Falkland Islands , Anthony Nelson, Shorpshire 1997, ISBN 0904614-60-3

Web links

Commons : Magellangans  - album with pictures, videos and audio files

Individual evidence

  1. Kolbe, s. 153
  2. Hans-Günther Bauer, Einhard Bezzel and Wolfgang Fiedler (eds.): The compendium of birds in Central Europe: Everything about biology, endangerment and protection. Volume 1: Nonpasseriformes - non-sparrow birds , Aula-Verlag Wiebelsheim, Wiesbaden 2005, ISBN 3-89104-647-2 , p. 80
  3. Kear, p. 412
  4. Wood, p. 74
  5. Wood, pp. 74 and 75
  6. Wood, p. 75
  7. ^ Shirihai, p. 241
  8. Kolbe, p. 184