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兔子也会成为濒危物种吗[文章版权 禁止转载:考试与评价 uvi?L7o tnI2vFroG]
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提到兔子，大家大概会想到的词有“可爱”、“乖巧”和“敏捷”等等，但几乎没有人会认为兔子也会和“濒危”联系到一起。兔子是以繁殖力强著称的物种，怎么会面临灭绝的危险呢？
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Eight years ago the smallest rabbits in North America were nearly extinct in Washington State.
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While pygmy rabbits live in several western states, the population in the Columbia River Basin has been isolated for thousands of years and is on the endangered species list. As the rabbits’ sagebrush steppe habitat was converted to agriculture, their numbers fell; in 2001, fewer than 30 were known to live in the state Biologists trapped 16 rabbits and began a captive-breeding program. But the one-pound pygmies couldn’t make healthy babies, so Idaho relatives were imported to broaden the gene pool.
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Today about 80 live in captivity. On March 13, 2007, scientists released 20 rabbits, which scampered into drainage pipes that serve as temporary into drainage pipes that serve as temporary burrows. But by September, predators had eaten all except one. Biologists are thinking of ways to make a second release go better: for example, placing the rabbits in a fenced-off area or even getting rid of some of those wily coyotes.
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