Can olive groves support bat conservation during winter? A case study from Tuscany, Italy

Abstract: The increasing pressures on bats, which play an important role in pest control, are
intensifying as temperatures continue to rise due to climatic changes, as well as agricultural
expansion continues to meet the demands of a growing global population. This study examines the impact of rising winter temperatures on bat activity in olive agroforestry systems in Tuscany, Italy. Across 12 organic olive groves and 4 associated semi-natural habitat sites in our study area, we used passive acoustic monitoring to investigate their role as activity and food reservoirs for bats during December 2023. Within three consecutive nights per site, we recorded 159 bat passes from 8 species, suggesting hibernation arousal for 7 of them. The average nightly recording temperature was 13.5 °C, with the lowest recording at 7 °C. Species-specific temperature thresholds were identified and comparatively reduced activity was observed in common urban species. Furthermore, our results indicate higher winter bat activity in olive agroforestry systems with low surrounding semi-natural habitat (SNH < 10 %) compared to those with high semi-natural habitat (SNH < 50 %). Our results highlight the disturbance effects of increased winter temperatures on hibernating bats at local and landscape scales, with implications for their conservation and pest control services, as well as the potential of organic olive groves as winter reservoirs under future climatic conditions.