Abstract
IntroductionBats are threatened by agricultural intensification, and although bat ecology in agricultural landscapes is in the focus of current research, the effects of interacting spatiotemporal factors on species-specific bat activity above farmland remain understudied. Our aim was to identify spatiotemporal factors and their interactions relevant for the activity of bat species above conventionally managed arable fields.MethodsWe repeatedly monitored relative bat activity above open arable fields in Germany using acoustic monitoring. We used site-related biotic and abiotic factors and landscape characteristics across five spatial scales, their combinations, and interactions to identify those factors which best explain variation in bat activity.ResultsNumerous interactions between landscape characteristics and the insect abundance affected bat activity above fields. For instance, Pipistrellus pipistrellus became more active with increasing insect abundance, but only above fields with a low proportion of woody vegetation cover in the surroundings. Additionally, the level of bat activity in summer depended on landscape characteristics. For example, the activity of Pipistrellus nathusii was relatively low in summer above fields that were surrounded by vegetation patches with a high degree of edge complexity (e.g., hedgerow). However, the activity remained at a relatively high level and did not differ between seasons above fields that were surrounded by vegetation patches with a low degree of edge complexity (e.g., roundly shaped forest patch).ConclusionsOur results revealed that landscape characteristics and their interactions with insect abundance affected bat activity above conventionally managed fields and highlighted the opportunistic foraging behavior of bats. To improve the conditions for bats in agricultural landscapes, we recommend re-establishing landscape heterogeneity to protect aquatic habitats and to increase arthropod availability.
Highlights
Bats are threatened by agricultural intensification, and bat ecology in agricultural landscapes is in the focus of current research, the effects of interacting spatiotemporal factors on species-specific bat activity above farmland remain understudied
We found that the effect of landscape characteristics on the activity of N. noctula and P. nathusii above arable fields was associated with stronger variation in bat activity during summer compared to autumn
The level of bat activity above arable fields during summer depends on landscape characteristics We found that depending on the parameter value and type of landscape characteristics, bat activity either remained on a relatively high level across seasons or decreased to lower levels in summer, which represents the most energy demanding time period of reproduction (Fig. 4, Additional file 10)
Summary
Bats are threatened by agricultural intensification, and bat ecology in agricultural landscapes is in the focus of current research, the effects of interacting spatiotemporal factors on species-specific bat activity above farmland remain understudied. In the face of a growing world population and the predicted agricultural land expansion and further intensification (Tilman et al 2011; Tilman et al 2001), it becomes increasingly important to understand the ecological dynamics in agricultural landscapes in order to mitigate environmental degradation and to sustain ecosystem functioning in the future In this context, European bats (Chiroptera) represent a interesting taxon for two reasons. Due to species-specific adaptations in wing morphology (Norberg and Rayner 1987), bat species differ in flight characteristics, such as flight speed and maneuverability These flight characteristics are associated with the bat species’ mobility which can affect the spatial scale of habitat use (Bader et al 2015). The habitat use of bats in agricultural landscapes changes with the season (Ciechanowski 2015; Heim et al 2016) since it is tightly associated with the annual reproductive life cycle of most European bat species (Mackie and Racey 2007; Racey and Swift 1985)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
