Large, long‐lived species with slow life histories and protracted pre‐breeding stages are particularly susceptible to declines and extinction, often for unknown causes. Here, we show how demographic modeling of a medium‐sized raptor, the Red Kite Milvus milvus, can aid to refocus conservation research and attention on the most likely mechanisms driving its decline. Red Kites’ survival and reproduction increased through three sequential stages for 1–2, 3–6, and 7–30 yr of age, mainly corresponding to individuals that are dispersing, attempting to gain a territory, and breeding. As typical of long‐lived species, elasticities were highest for adult (≥7 yr old) survival, but this was high, with little scope for improvement. Instead, the declines were driven by an extremely low survival of pre‐adults in their first years of life, which weakened the whole demographic system by nullifying the offspring contribution of adults and curtailing their replacement by recruits. For example, 27 pairs were necessary to generate a single prime age adult. Simulation of management scenarios suggested that the decline could be halted most parsimoniously by increasing pre‐adult survival to the mean levels recorded for other areas, while only the synergistic, simultaneous improvement of breeding success, adult and pre‐adult survival could generate a recovery. We propose three actions to attain such goals through selective supplementary feeding of both breeding and non‐breeding individuals, and through mortality improvement by GPS remote‐sensing devices employed as surveillance monitoring tools. Our results show how improving demographic models by using real, local vital rates rather than “best guess” vital rates can dramatically improve model realism by refocusing attention on the actual stages and mortality causes in need of manipulation, thus building precious time and resources for conservation management. These results also highlight the frequent key role of pre‐adult survival for the management of long‐lived species, coherent with the idea of demographic systems as integrated chains only as strong as their weakest link.

中文翻译：

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人口模型以微调保护目标：成年成年人对濒临灭绝的猛禽的衰落的重要性

大型的，长寿的物种，具有缓慢的生活史和较长的繁殖前期，特别是由于未知的原因，特别容易衰退和灭绝。在这里，我们展示了中型猛禽Red Kite Milvus milvus的人口统计建模可以帮助将保护性研究重新集中在驱动其衰退的最可能机制上。红色风筝的生存和繁殖在1–2、3–6和7–30岁的三个连续阶段中有所增加，主要对应于散布，试图获得领土并繁殖的个体。作为长寿物种的典型代表，成年（≥7岁）存活的弹性最高，但这很高，几乎没有改善的余地。取而代之的是，下降的原因在于成年后第一年的成年后存活率极低，这使成年子女的后代无效并减少了新兵的成年，从而削弱了整个人口统计系统。例如，要生成一个单身的成年成年人，就需要27对。管理情景的模拟表明，可以通过将成年前的存活率提高到其他地区记录的平均水平来最大程度地阻止这种下降，而只有协同，同时提高育种成功率，成年和成年前的存活率才能产生恢复。我们提出了三项行动，以通过有选择地补充育种和非育种个体的补充饲料，以及通过将GPS遥感设备用作监视监测工具来提高死亡率来实现这些目标。我们的结果表明，通过使用实际的局部生命率而不是“最佳猜测”生命率来改善人口统计模型，可以通过将注意力重新集中在需要操纵的实际阶段和死亡原因上，从而极大地改善模型的真实性，从而为保护管理建立了宝贵的时间和资源。这些结果也凸显了成年前生存在长寿物种管理中的频繁关键作用，这与人口统计系统的概念相联系，即综合链只有其最薄弱的环节才有力。