Edge effects and vertical stratification of aerial insectivorous bats across the interface of primary-secondary Amazonian rainforest

Edge effects, abiotic and biotic changes associated with habitat boundaries, are key drivers of community change in fragmented landscapes. Their influence is heavily modulated by matrix composition. With over half of the world’s tropical forests predicted to become forest edge by the end of the century, it is paramount that conservationists gain a better understanding of how tropical biota is impacted by edge gradients. Bats comprise a large fraction of tropical mammalian fauna and are demonstrably sensitive to habitat modification. Yet, knowledge about how bat assemblages are affected by edge effects remains scarce. Capitalizing on a whole-ecosystem manipulation in the Central Amazon, the aims of this study were to i) assess the consequences of edge effects for twelve aerial insectivorous bat species across the interface of primary and secondary forests and ii) investigate if the activity levels of these species differed between the understory and canopy and if they were modulated by d..., Acoustic recordings were collected from the Central Brazilian Amazon, 80 km north of Manaus, at the Biological Dynamics of Forest Fragments Project (BDFFP; 2024’26’’S, 59043’40’’W). Two static detectors (SM2Bat+, Wildlife Acoustics) with omnidirectional microphones (SMX-US Ultrasonic Microphone) were placed in the understory and canopy of 164 sample points. These sample points were spaced 50 m apart along four 2 km transects. Transects were located across two spatially independent sites to reduce site bias. Each transect extended through 1 km of secondary forest and then continued 1 km into the neighbouring primary forest. Surveys were conducted in the dry season of 2013 and the wet season of 2014 to minimise seasonal bias, equating to eight transect visits in total. The understory was defined as extending from the ground to a height of approximately 10 m and the canopy was defined as approximately 30 m from ground level. To ensure the understory and canopy samples were independent, pla..., , # Edge effects and vertical stratification of aerial insectivorous bats across the interface of primary-secondary Amazonian rainforest [https://doi.org/10.5061/dryad.0vt4b8h2d](https://doi.org/10.5061/dryad.0vt4b8h2d) ### Column headings and details * Season: Season when the data was collected * Edge1 = dry season (July - October 2013) * Edge2 = wet season (November and June 2014) * Location: One of two sites across the Biological Dynamics of Forest Fragments Project, Cabo Frio or Dimona * Transect: One of four transects. There are two transects per location * Distance: Distance from the habitat edge (m) * Minus values represent secondary forest * Positive values represent primary forest * 0 represents habitat boundary * Habitat: Either understory (U) or canopy (C) where detectors were placed * Species: Species/sonotype codes * *Cormura brevirostris (CB)* * *Centronycteris maximiliani/centralis (CM)* * *Eptesicus brasilie...边缘效应（Edge effects）指与生境边界相关的非生物（abiotic）与生物（biotic）变化，是破碎化景观中群落变化的关键驱动因子。其作用强度很大程度上受基质组成（matrix composition）调控。据预测，到本世纪末全球超过一半的热带森林将转变为林缘（forest edge），因此保护工作者亟需深入了解热带生物区系（tropical biota）如何受边缘梯度（edge gradients）的影响。蝙蝠在热带哺乳类动物区系中占比可观，且已被证实对生境改造极为敏感，但目前关于蝙蝠类群（bat assemblages）如何受边缘效应影响的认知仍十分匮乏。本研究依托亚马逊中部的全生态系统操控实验（whole-ecosystem manipulation），旨在达成两个目标：① 评估原生林（primary forest）与次生林（secondary forest）界面处的边缘效应对12种食虫性蝙蝠（aerial insectivorous bat）的影响；② 探究这些物种的活动水平在林下层（understory）与冠层（canopy）之间是否存在差异，以及是否受d…… 本研究的声学录音（acoustic recordings）采集自巴西亚马逊中部马瑙斯以北80公里处的森林碎片生物动力学项目（Biological Dynamics of Forest Fragments Project, BDFFP；坐标：2°26′S, 59°43′40′′W）。研究使用2台搭载全向超声麦克风（SMX-US Ultrasonic Microphone）的静态声学检测器（SM2Bat+, Wildlife Acoustics），布设至164个采样点的林下层与冠层中。这些采样点沿4条2公里长的样带（transects）布设，样带间间隔50米。为降低位点偏差（site bias），样带分布在2个空间独立的研究位点。每条样带依次穿过1公里次生林，随后延伸1公里至相邻的原生林内。为最小化季节偏差（seasonal bias），调查分别于2013年旱季与2014年雨季开展，总计完成8次样带走访。本研究将林下层定义为从地面至约10米高度的区域，冠层定义为距地面约30米的区域。为确保林下层与冠层采样相互独立，pla…… # 亚马逊原生-次生林界面食虫性蝙蝠的边缘效应与垂直分层 [https://doi.org/10.5061/dryad.0vt4b8h2d](https://doi.org/10.5061/dryad.0vt4b8h2d) ### 列标题及详细说明 * 季节（Season）：数据采集季节 * Edge1 = 旱季（2013年7-10月） * Edge2 = 雨季（2014年11月与2014年6月） * 位点（Location）：森林碎片生物动力学项目的2个独立位点之一，即Cabo Frio或Dimona * 样带（Transect）：4条样带之一，每个位点各设2条样带 * 距离（Distance）：与生境边界的距离（单位：米） * 负值代表次生林 * 正值代表原生林 * 0代表生境边界 * 生境层位（Habitat）：检测器布设的生境类型，林下层（U）或冠层（C） * 物种（Species）：物种/声型（sonotype）代码 * *Cormura brevirostris*（CB） * *Centronycteris maximiliani/centralis*（CM） * *Eptesicus brasilie……*