Before he began to catalogue them as a postgraduate, drawing up in 1988 an action plan to save them, all 23 species of crocodilians were threatened or declining.

1988年，即在他作为一名研究生起草一份拯救鳄鱼的行动计划而对鳄鱼进行登记分类之前，所有23种鳄鱼都受到威胁或濒危。

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Before he began to catalogue them as a postgraduate, drawing up in 1988 an action plan to save them, all 23 species of crocodilians were threatened or declining.

1988年，即在他作为一名研究生起草一份拯救鳄鱼的行动计划而对鳄鱼进行登记分类之前，所有23种鳄鱼都受到威胁或濒危。

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