Gomes Dylan G E, Appel Giulliana, Barber Jesse R
Department of Biological Sciences, Boise State University, Boise, ID, USA.
Programa de Pós-graduação em Ecologia, Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil.
PeerJ. 2020 Dec 18;8:e10591. doi: 10.7717/peerj.10591. eCollection 2020.
Previous research has shown diverse vertical space use by various taxa, highlighting the importance of forest vertical structure. Yet, we know little about vertical space use of tropical forests, and we often fail to explore how this three-dimensional space use changes over time.
Here we use canopy tower systems in French Guiana and passive acoustic monitoring to measure Neotropical bat activity above and below the forest canopy throughout nine nights. We use a Bayesian generalized linear mixed effect model and kernel density estimates to demonstrate patterns in space-use over time.
We found that different bats use both canopy and understory space differently and that these patterns change throughout the night. Overall, bats were more active above the canopy (including and ), but multiple species or acoustic complexes (when species identification was impossible) were more active in the understory (such as and ). We also found that most bats showed temporally-changing preferences in hourly activity. Some species were less active (e.g., and ), whereas others were more active (, and ) on nights with higher moon illuminance.
Here we show that Neotropical bats use habitat above the forest canopy and within the forest understory differently throughout the night. While bats generally were more active above the forest canopy, we show that individual groups of bats use space differently over the course of a night, and some prefer the understory. This work highlights the need to consider diel cycles in studies of space use, as animals use different habitats during different periods of the day.
先前的研究表明，不同分类群对垂直空间的利用方式多样，凸显了森林垂直结构的重要性。然而，我们对热带森林垂直空间的利用了解甚少，而且常常未能探究这种三维空间利用方式如何随时间变化。
在此，我们利用法属圭亚那的树冠塔系统和被动声学监测，在九个夜晚测量新热带界蝙蝠在树冠层上方和下方的活动情况。我们使用贝叶斯广义线性混合效应模型和核密度估计来展示随时间的空间利用模式。
我们发现，不同的蝙蝠对树冠层和林下空间的利用方式不同，且这些模式在整个夜晚都会发生变化。总体而言，蝙蝠在树冠层上方（包括 和 ）更为活跃，但多个物种或声学复合体（当无法进行物种识别时）在林下（如 和 ）更为活跃。我们还发现，大多数蝙蝠在每小时的活动中表现出随时间变化的偏好。在月光照度较高的夜晚，一些物种活跃度较低（如 和 ），而其他物种则更为活跃（ 、 和 ）。
我们在此表明，新热带界蝙蝠在整个夜晚对树冠层上方和森林林下的栖息地利用方式不同。虽然蝙蝠通常在树冠层上方更为活跃，但我们表明，不同蝙蝠群体在一个夜晚的过程中对空间的利用方式不同，有些更喜欢林下空间。这项工作强调了在空间利用研究中考虑昼夜周期的必要性，因为动物在一天中的不同时间段使用不同的栖息地。
