Identifying efficient biodiversity indicators is a key pillar of the global conservation strategy. Top predators have been proposed as reliable biodiversity signposts, but their role is controversial. Here, we verified their performance by a meta-analysis of published studies and found solid support for their efficacy as biodiversity indicators. As to be expected for any indicator species, efficacy was stronger for biodiversity components ‘ecologically closer’ to the predator (i.e. broad groups that include species providing key resources, such as avian and tree diversity for a bird-eating predator that nests in trees) and declined for the diversity of components more ‘ecologically remote’ from the predator (e.g. butterfly diversity for a fish-eating predator). This confirmed a link between the top predatory role and biodiversity and set the context for its functionality. These results show that, on average, top predators are justified candidates as biodiversity indicators and that prioritisation of conservation action based on their occurrence is likely to provide broader ecosystem benefits. However, such role should be confirmed on a case-by-case basis, acknowledging that no indicator can portray everything, checking the compatibility of the biodiversity components linked to the predator with the established conservation objectives and ideally integrating predators with other complementary indicator groups.

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作为生物多样性指标的顶级捕食者：荟萃分析

确定有效的生物多样性指标是全球保护战略的关键支柱。顶级捕食者被提议作为可靠的生物多样性路标，但它们的作用是有争议的。在这里，我们通过对已发表研究的荟萃分析验证了它们的性能，并为它们作为生物多样性指标的功效找到了坚实的支持。正如任何指标物种所预期的那样，生物多样性成分在“生态上更接近”捕食者（即包括提供关键资源的物种的广泛群体，例如鸟类和树木多样性对于筑巢在树上的食鸟捕食者而言）的效力更强并且由于远离捕食者的“生态上”更远的成分的多样性（例如食鱼捕食者的蝴蝶多样性）而下降。这证实了顶级掠夺性角色与生物多样性之间的联系，并为其功能设定了背景。这些结果表明，平均而言，顶级捕食者作为生物多样性指标是合理的候选者，并且基于它们的发生对保护行动进行优先排序可能会提供更广泛的生态系统利益。然而，这种作用应逐案确认，承认没有指标可以描述一切，检查与捕食者相关的生物多样性组成部分与既定保护目标的兼容性，并在理想情况下将捕食者与其他补充指标组结合起来。顶级捕食者是生物多样性指标的合理候选者，基于它们的发生对保护行动进行优先排序可能会提供更广泛的生态系统利益。然而，这种作用应逐案确认，承认没有指标可以描述一切，检查与捕食者相关的生物多样性组成部分与既定保护目标的兼容性，并在理想情况下将捕食者与其他补充指标组结合起来。顶级捕食者是生物多样性指标的合理候选者，基于它们的发生对保护行动进行优先排序可能会提供更广泛的生态系统利益。然而，这种作用应逐案确认，承认没有指标可以描述一切，检查与捕食者相关的生物多样性组成部分与既定保护目标的兼容性，并在理想情况下将捕食者与其他补充指标组结合起来。