Protecting just 42 sites across Asia, ranging from temperate forests to tropical grasslands, could be key to the survival of one

admin2012-08-05  29

问题     Protecting just 42 sites across Asia, ranging from temperate forests to tropical grasslands, could be key to the survival of one of the world’s most symbolic and feared, wild cats—the tiger.
    That radical proposal, published online in the journal Public Library of Science-. Biology, represents a scaling-back of ambition and what one of the paper’s authors calls "ruthless priority setting". "It’s forcing hard decisions," said Simon Stuart, co-author of the paper, who chairs the species survival commission at the International Union for Conservation of Nature. For animals that are worth considerable sums, he added, "there’s no way you can protect them across an entire landscape, because the costs are too high".
    John Robinson, executive vice president for conservation and science at the Wildlife Conservation Society, said researchers experienced "a real shock" when they determined what was needed to keep the species going. The majority of about 1 000 breeding females are found in India, Russia and Indonesia. None remain in Cambodia, China, DPRK and Vietnam. "Unless we protect those core populations, within a few short years we could lose tigers altogether," said Robinson, another of the paper’s co-authors.
    Over the past couple of decades, environmentalists have focused on preserving large, ecologically rich landscapes to ensure that a wide range of plant and animal species can thrive over the long term. But for a number of highly endangered species, scientists now say, governments and nonprofit organizations must target their efforts more narrowly if they want to ensure that these populations remain viable.
    In the case of the tiger, three factors—habitat loss, the overhunting of its prey and poaching (偷猎)— have caused its number to drop from more than 10 000 in the 1980s to fewer than 3 500 today. It is said that tiger parts are so prized in Eastern medicine that a dead one can sell for $ 1 500 to $ 3 500 before its eyes are sold as a cure for some complicated diseases and are converted into a soup for the body, and its bones are ground into powder to treat some diseases like typhoid (伤寒). Researchers have determined that tigers occupy less than 7 percent of their historic range. In addition to poaching, Asia’s rapid economic development—including road and dam construction—has eroded tiger habitat.
    Robinson and others advocate a two-step process that focuses on monitoring and protecting tigers in the 42 source sites and a longer-term effort to preserve the large landscapes tigers need to hunt and wander.
The number of tigers has decreased since the 1980s due to the overhunting of its prey,______.

选项

答案habitat loss and poachlng

解析 信息明示题。本题考查自从20世纪80年代以来老虎数量锐减的原因。根据定位句可知,三大因素导致了这一结果,其中包括栖息地的丧失、对老虎猎物的过度捕猎以及偷猎。题干中的The number of…decreased是对原文中its number to drop的同义转述。
转载请注明原文地址:https://jikaoti.com/ti/e8rFFFFM
0

最新回复(0)