美國(guó)官方尋找鯉魚問(wèn)題的解決辦法。

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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 …
上周我們的主題是非法捕魚。今天我們報(bào)道的兩個(gè)案例中，魚既是受害者又是罪犯。 第一個(gè)案例涉及到了兩種亞洲鯉魚-鳙魚和鰱魚。它們能長(zhǎng)到一米多長(zhǎng)，會(huì)吃掉比其它魚類更多的浮游物以維持生存。鰱魚還能跳出水面襲擊船員。 亞洲鯉魚是在二十世紀(jì)七十年代的時(shí)候引進(jìn)的，用于吞食海藻及其它水中的微生物。它們作為清潔工被…