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The eradication of the North American beaver in Tierra del Fuego is being attempted by the governments of Chile and Argentina in this area at the southernmost tip of South America. The non-native species was introduced in 1946 as a potential source of commercial fur trading. When the fur trade industry was unsuccessful, however, the beavers became problematic and the governments agreed to intervene. A June 2011 NPR report stated that the beavers have caused millions of dollars in damages. According to ''Nature'', this plan is the largest eradication project ever attempted. ==Background and history== In 1946, the Argentinian government imported fifty beavers from Canada. The beavers were the putative catalyst for the administration's failed attempt to promote commercial fur trading.〔 The North American beavers have no natural predators in the area. In their native habitats such as Canada, bears and wolves prey on the beavers and keep the population under control. One observer noted that anyone considering importing beavers should also import bears, those being beavers' natural predators.〔 According to a June 2011 NPR report, 200,000 beavers are living in the area.〔 Another report puts the number in excess of 100,000, and states the level of destruction as akin to having bulldozers thrashing through the area. Tierra del Fuego National Park in Argentina is especially threatened, as the beavers are destroying long-protected trees. The animals have spread beyond Tierra del Fuego itself into the Brunswick Peninsula of Chile, and the government fears further penetration into continental South America.〔 The beavers already threaten around sixteen million hectares of indigenous forest.〔 Unlike many trees in North America, trees in South America often do not regenerate when coppiced, destroying the forest. As well as felling trees, beavers create dams that flood certain areas and thus drown other trees and vegetation.〔(short documentary about the beavers and the damage they cause in Tierra del Fuego Province, Chile, "Beavers in Tierra del Fuego" ) livingatlasofchile.com released on January 13, 2013 retrieved February 18, 2014〕 Flooding from beaver dams also damages roads and cattle-grazing pastures.〔 Ecologist Christopher Anderson, professor at the Universidad de Magallanes, has said, "The change in the forested portion of this biome is the largest landscape-level alteration in the Holocene — that is, approximately 10,000 years". 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「Beaver eradication in Tierra del Fuego」の詳細全文を読む スポンサード リンク
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