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Amsterdam Island cattle was a rare feral breed of wild cattle (''Bos taurus'') that had existed in isolation on Amsterdam Island, a small French territory in the southern Indian Ocean, from 1871 to 2010 when the population was eradicated in the course of an environmental restoration program. ==History== On 18 January 1871 an attempt to settle the then uninhabited 55 km2 island was made by a party led by Heurtin, a French farmer (sometimes described as a peasant) from Réunion. After seven months, their attempts to raise sheep and cattle and grow crops had been unfruitful and they departed on 19 August, abandoning their livestock, including five cattle, on the island.〔Carroll (2003).〕 Over the next century or so a combination of factors caused further ecological devastation of the island, which had already been impacted by the introduction of invasive species of plants and animals, as well as by unrestricted hunting, timber-cutting and wildfire caused by sealers and other visitors. The Amsterdam duck and several species of petrel became extinct, and the breeding population of the endemic Amsterdam Island albatross, previously thought to be a subspecies of the wandering albatross, was reduced to just five pairs.〔Micol & Jouventin (1995).〕 When the native ''Phylica arborea'' (syn. ''Phylica nitida'') forest was almost entirely destroyed, grazing by the increasing numbers of cattle prevented natural regeneration. From the original five animals the cattle population grew to about 2000, which occupied an area of 3000 ha, at a density of 0.64 individuals per hectare. The only part of the island unoccupied by cattle was the Plateau des Tourbières, over 550 m above sea level.〔 However, despite the threat posed by the cattle to the island’s environment, they formed one of the very few herds of feral ''Bos taurus'' anywhere in the world.〔 In 1987, in order to mitigate the damaging impact the cattle were having on the flora and fauna of Amsterdam, as well as to preserve the breed because of scientific interest in its isolation-derived genetic character, a fence was built across the island. During 1988 and 1989 the cattle south of the fence (1059 animals) were culled. Since then the cattle have been restricted to the northern part of Amsterdam. About 50-80 mainly adult and subadult males out of a herd of about 350 individuals were shot each year to provide fresh meat for the inhabitants of the Martin-de-Viviès research station, the only settlement on the island.〔Berteaux & Micol (1992).〕 In 2007, after a study has shown that the areas that were not grazed were recolonized by native plants, it was decided to kill all of the remaining cattle on the island. An association of people who formerly were wintering on the island tried to oppose the decision, but in vain. The slaughter began in 2008 and ended in 2010.〔Sophie Lautier: "Sur l'île Amsterdam, chlorophylle et miaulements".〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Amsterdam Island cattle」の詳細全文を読む スポンサード リンク
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