That number is smaller than current figures for the effective population size (or number of breeding individuals) for endangered species such as chimpanzees (21, 000) and gorillas (25, 000).

当时的人数甚至不及现在濒临灭绝的黑猩猩（21000头）和大猩猩（25000头）的有效种群大小（即能生育的个体数量）。

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Larviciding measures at mosquito breeding sites are the most effective form of vector control if breeding sites can be clearly identified and are limited in size and extent.

如果蚊子滋生地点可以明确确定并且范围和程度有限，就地采取杀幼虫措施就是十分有效的媒介控制形式。

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