美国官方寻找鲤鱼问题的解决办法。

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Last week our subject was illegal fishing. Now we report on 2 cases where fish are both the victims and the offenders. The first involves 2 kinds of Asian carp, bighead and silver. They can grow more than a meter long and weigh up to 45 kilos. They eat huge amounts of plankton that other fish need …
上周我们的主题是非法捕鱼。今天我们报道的两个案例中，鱼既是受害者又是罪犯。 第一个案例涉及到了两种亚洲鲤鱼-鳙鱼和鲢鱼。它们能长到一米多长，会吃掉比其它鱼类更多的浮游物以维持生存。鲢鱼还能跳出水面袭击船员。 亚洲鲤鱼是在二十世纪七十年代的时候引进的，用于吞食海藻及其它水中的微生物。它们作为清洁工被…