Even when endangered populations recover, it has proved difficult to reduce or remove CITES protection.

即使濒危物种数量恢复，降低或者去除CITES的保护措施也十分困难。

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Second, it may be difficult to identify which industry or potential industry qualifies for this treatment, and experience bha shown that protection, once given, is difficult to remove.

第二，很难确定哪项工业或潜在工业符合这些要求，经验表明，一旦给予保护就很难撤销。

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