Morrison Catriona A, Butler Simon J, Robinson Robert A, Clark Jacquie A, Arizaga Juan, Aunins Ainars, Baltà Oriol, Cepák Jaroslav, Chodkiewicz Tomasz, Escandell Virginia, Foppen Ruud P B, Gregory Richard D, Husby Magne, Jiguet Frédéric, Kålås John Atle, Lehikoinen Aleksi, Lindström Åke, Moshøj Charlotte M, Nagy Károly, Nebot Arantza Leal, Piha Markus, Reif Jiří, Sattler Thomas, Škorpilová Jana, Szép Tibor, Teufelbauer Norbert, Thorup Kasper, van Turnhout Chris, Wenninger Thomas, Gill Jennifer A
School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
British Trust for Ornithology, The Nunnery, Thetford IP24 2PU, UK.
Proc Biol Sci. 2021 Mar 10;288(1946):20202955. doi: 10.1098/rspb.2020.2955. Epub 2021 Mar 3.
Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines.
针对常见且分布广泛但数量正在减少的物种的野生动物保护政策，很难有效设计和实施，因为多种环境变化可能导致种群数量下降。保护行动最终旨在影响种群动态率，但对于分布广泛、栖息地涵盖多种环境条件的物种而言，将行动目标设定为切实改善这些动态率颇具挑战。在欧洲，候鸟数量急剧下降引发了国际社会呼吁采取行动，但尚未确定哪些行动能够切实有助于种群数量恢复。改善低质量栖息地条件的针对性行动可能是一种有效方法，但前提是当地条件持续影响当地种群动态，进而影响种群趋势。通过对欧洲各地调查点繁殖鸟类的数量和种群动态进行长期测量，我们发现，具有不同迁徙行为的共生物种在当地种群趋势方向和生产力幅度上相似，但存活率不同。因此，在欧洲采取针对性行动提高当地生产力，同时在非繁殖地进行大规模（非针对性）环境保护，可能有助于满足迫切需要，阻止候鸟数量下降。这种通过种群动态实现恢复的途径，对于应对全球野生动物数量下降可能越来越必要。
