Not only hedgerows, but also flower fields can enhance bat activity in intensively used agricultural landscapes

Agri-environment schemes (AES) have become important tools for farmland biodiversity conservation, providing suitable habitats, resources, and connectivity within agricultural landscapes. Bats are rarely studied in relation to AES effectiveness in contrast to birds, even though their presence and activity as biological control agents on insects, especially pest species, can be important for agricultural crops. While the role of hedgerows for bat occurrence and activity, as well as for their prey's diversity and abundance has been widely studied, the role of other AESs such as flower fields remains unclear. We monitored the activity of the main functional groups (edge, narrow and open space foragers) using ultrasound recorders, as well as potential prey abundances using light traps, across 35 study sites representing different AES in Central Germany from late July to September 2018. The sampled AES consisted of annual flower fields, mixed flower fields (with annual and biennial vegetatio..., Bats were recorded with ultrasound recorders (Song Meter SM2Bat + model, Wildlife Acoustics, Inc.)
Potential insect prey was collected using light traps, each lamp possessed four small LED lights: green, blue and two UV (ELEKON AG, 2018), with wavelengths of λmax ∼530 nm, 465 nm, 340 nm, and 348 nm, and a total illuminance of 5 lx, powered by two AA NiMH batteries (Villarroya-Villalba et al., 2021).
We used QGIS 3.6 (Development Team, 2019) and information obtained from land use maps (SLA, 2018) to digitise agricultural fields and landscape elements based on satellite images (Map data ©2019 Google based on GoogleSatellite plugin).
All statistical analyses were conducted in R 3.6.0 (R Development Core Team, 2019). , The datasets are in .csv format, which open in the R Software (R Development Core Team, 2019).