Epsilon Archive for Student Projects

Abstract

Ecosystem restoration through the reintroduction of grazers is gaining interest across Europe. Large herbivores are associated with landscape heterogeneity, restoration of trophic cascades and biodiversity. Projects implementing this form of trophic rewilding benefit from adequate monitoring techniques to assess the progress of ecosystem restoration. Bats have been put forward as suitable bioindicators, providing generalizable insight into responses of a multitude of taxonomic orders further down the food chain. At the same time, novel acoustic methods such as the AudioMoth allow for upscaling studies concerning the behavior of sound producing animals, which may be used to monitor progress of rewilding projects. In this study, I explored the relative detection probabilities of the AudioMoth in cluttered, edge and open habitat types, where clutter refers to areas with more trees and understory vegetation. Clutter reduced detection probability with the AudioMoth with sounds played over a speaker at 10kHz and at three ascending volumes. The AudioMoths were also used to assess the impact of three habitat types (forest, forest edge and open grassland) on the presence of functionally different bat genera, by placing the devices in each habitat to record bats for 3-4 days over the course of three months. The forest-adapted genus Plecotus was not more likely to be detected in any of the habitats. I did find evidence that the edge-adapted genus Myotis was more likely to be detected in open compared to forest habitat, and open-adapted genera Nyctalus and Seronitus were more likely to be detected in forest edges and open grasslands compared to forest habitats. Lastly, I compared bat genus richness between a rewilded area and its non-rewilded nature surroundings in Dutch national landscape ‘Het Groene Woud’. There was no effect of rewilding on genus richness. Further efforts to monitor rewilding projects should consider the methods used in this study, as AudioMoth provides a low-cost and energy-efficient option, and bats an indication of wider taxonomic patterns. My data and findings may be used as a baseline study for bat and rewilding research in the local context of Het Groene Woud.