Landscape composition drives the impacts of artificial light at night on insectivorous bats

• Published in: Environmental Pollution
• Main Authors: Barré, Kévin, Vernet, Arthur, Azam, Clémentine, Le Viol, Isabelle, Dumont, Agathe, Deana, Thomas, Vincent, Stéphane, Challéat, Samuel, Kerbiriou, Christian
• Other Authors: Muséum national d'Histoire naturelle (MNHN), Centre d'Ecologie et des Sciences de la COnservation (CESCO), Muséum national d'Histoire naturelle (MNHN)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire de l'environnement nocturne (OEN), Géographie de l'environnement (GEODE), Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Union internationale pour la conservation de la nature UICN (UICN), Université Paris Descartes - École de sages-femmes Baudelocque (UPD ESF Baudelocque), Université Paris Descartes - Paris 5 (UPD5), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), ANR-11-LABX-0010,DRIIHM / IRDHEI,Dispositif de recherche interdisciplinaire sur les Interactions Hommes-Milieux(2011)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SHS.GEO]Humanities and Social Sciences/Geography; [SDE.ES]Environmental Sciences/Environment and Society; [SHS.ENVIR]Humanities and Social Sciences/Environmental studies; [SHS.ARCHI]Humanities and Social Sciences/Architecture; space management; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDE.MCG]Environmental Sciences/Global Changes; Gleaner; Pipistrellus pipistrellus
• Online Access: https://hal.science/hal-03748316; https://hal.science/hal-03748316/document; https://hal.science/hal-03748316/file/S026974912101976X.pdf; https://doi.org/10.1016/j.envpol.2021.118394

International audience Among the most prevalent sources of biodiversity declines, Artificial Light At Night (ALAN) is an emerging threat to global biodiversity. Much knowledge has already been gained to reduce impacts. However, the spatial variation of ALAN effects on biodiversity in interaction with landscape composition remains little studied, though it is of the utmost importance to identify lightscapes most in need of action. Several studies have shown that, at local scale, tree cover can intensify positive or negative effects of ALAN on biodiversity, but none haveat landscape scalestudied a wider range of landscape compositions around lit sites. We hypothesized that the magnitude of ALAN effects will depend on landscape composition and species' tolerance to light. Taking the case of insectivorous bats because of their varying sensitivity to ALAN, we investigated the species-specific activity response to ALAN. Bat activity was recorded along a gradient of light radiance. We ensured a large variability in landscape composition around 253 sampling sites. Among the 13 bat taxa studied, radiance decreased the activity of two groups of the slow-flying gleaner guild (Myotis and Plecotus spp.) and one species of the aerialhawking guild (Pipistrellus pipistrellus), and increased the activity of two species of the aerial-hawking guild (Pipistrellus kuhlii and Pipistrellus pygmaeus). Among these five effects, the magnitude of four of them was driven by landscape composition. For five other species, ALAN effects were only detectable in particular landscape compositions, making the main effect of radiance undetectable without account for interactions with landscape. Specifically, effects were strongest in non-urban habitats, for both guilds. Results highlight the importance to prioritize ALAN reduction efforts in non-urban habitats, and how important is to account for landscape composition when studying ALAN effects on bats to avoid missing effects.