Data from: Subtle changes in elevation shift bat-assemblage structure in Central Amazonia

The distribution patterns of animal species at local scales have been explained by direct influences of vegetation structure, topography, food distribution and availability. However, these variables can also interact and operate indirectly on the distribution of species. Here, we examined the direct and indirect effects of food availability (fruits and insects), vegetation clutter and elevation in structuring phyllostomid-bat assemblages in a continuous terra firme forest in Central Amazonia. Bats were captured in 49 plots over 25-km² of continuous forest. We captured 1138 bats belonging to 52 species with 7056 nethours of effort. Terrain elevation was the strongest predictor of species and guild compositions, and of bat abundance. However, changes in elevation were associated with changes in vegetation clutter, and availability of fruits and insects consumed by bats, which are likely to have had direct effects on bat assemblages. Frugivorous-bat composition was more influenced by availability of food-providing plants, while gleaning-animalivore composition was more influenced by the structural complexity of the vegetation. Although probably not causal, terrain elevation may be a reliable predictor of bat-assemblage structure at local scales in other regions. In situations where it is not possible to collect local variables, terrain elevation can substitute other variables, such as vegetation structure, and availability of fruits and insects.局域尺度下的动物物种分布格局，既往研究多归因于植被结构、地形、食物分布及其可获得性的直接作用。然而，这些环境变量亦可相互作用，并间接影响物种分布。本研究聚焦亚马孙中部一片连续的terra firme 森林（terra firme forest），探讨了食物可获得性（果实与昆虫）、植被杂乱程度以及海拔在塑造叶口蝠科蝙蝠群落（phyllostomid bat assemblage）结构中的直接与间接效应。研究团队在25平方千米的连续森林内设置49个样地，累计开展7056网捕小时的采样工作，共捕获1138只蝙蝠，隶属于52个物种。结果显示，地形海拔是解释物种组成、功能群组成以及蝙蝠种群丰度的最强预测因子。然而，海拔变化与植被杂乱程度、蝙蝠所食用的果实与昆虫的可获得性变化密切相关，而这些因素均可能对蝙蝠群落结构产生直接影响。其中，食果蝙蝠的群落组成更多受供食植物可获得性的调控，而拾食性食虫蝙蝠的群落组成则更多受植被结构复杂性的影响。尽管海拔并非绝对的因果驱动因子，但它或可作为其他区域局域尺度下蝙蝠群落结构的可靠预测指标。在无法直接获取局域环境变量的场景中，地形海拔可替代植被结构、果实与昆虫可获得性等变量开展相关研究。