Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544.
Faculty of Science, Ecology and Genetics Research Unit, University of Oulu, Oulu FI-90014, Finland.
Proc Natl Acad Sci U S A. 2024 Nov 26;121(48):e2402652121. doi: 10.1073/pnas.2402652121. Epub 2024 Nov 18.
Nest predation rates critically influence avian biodiversity and evolution. In the north temperate zone, increased nest failure along edges of forest fragments is hypothesized to play a major role in the disappearance of bird species from disturbed landscapes. However, we lack comprehensive syntheses from tropical latitudes, where biodiversity is highest and increasingly threatened by habitat fragmentation and disturbance. We assembled data from five decades of field studies across the global tropics (1,112 populations of 661 species) and used phylogenetic models to evaluate proposed predictors of nest success. We found significant effects of several traits, including adult body mass and nest architecture. Contrary to results from many temperate locations, anthropogenic habitat disruption did not consistently reduce nest success; in fact, raw nest success rates were lower in large tracts of primary forest than in disturbed or fragmented landscapes. Follow-up analyses within species, using a subset of 76 species for which we had estimates of nest survival in habitats with different levels of disruption, confirmed that neither disturbance nor fragmentation significantly influenced nest success. These results suggest that nest predation alone cannot explain observed declines in avian biodiversity in tropical forest fragments, raising new questions about the demographic processes that drive extinction in the tropics.
巢捕食率对鸟类生物多样性和进化具有至关重要的影响。在北温带，森林碎片边缘的巢失败率增加被假设在受干扰景观中鸟类物种消失中起着主要作用。然而，我们缺乏来自热带地区的综合研究，而热带地区的生物多样性最高，并且越来越受到栖息地破碎化和干扰的威胁。我们汇集了来自全球热带地区五十年的实地研究数据（661 种的 1112 个种群），并使用系统发育模型来评估巢成功率的预期预测因子。我们发现了几个特征的显著影响，包括成年体质量和巢结构。与许多温带地区的结果相反，人为的生境破坏并不总是降低巢成功率；实际上，在大面积的原始森林中，原始巢成功率比受干扰或破碎化的景观中低。在对 76 个物种中的一部分进行的后续分析中，我们对具有不同破坏程度的生境中的巢存活率进行了估计，这证实了干扰或破碎化都没有显著影响巢成功率。这些结果表明，巢捕食本身不能解释热带森林碎片中观察到的鸟类生物多样性下降，这对热带地区驱动灭绝的人口过程提出了新的问题。
