Large-scale long-term passive-acoustic monitoring reveals spatio-temporal activity patterns of boreal bats

• Published in: Ecography
• Main Authors: Kotila, Miika, Suominen, Kati Marie, Vasko, Ville V., Blomberg, Anna S., Lehikoinen, Aleksi, Andersson, Tommi, Aspi, Jouni, Cederberg, Tony, Hänninen, Jari, Inkinen, Jasmin, Koskinen, Janne, Lundberg, Göran Magnus, Mäkinen, Katja, Rontti, Markku, Snickars, Martin, Solbakken, Jostein Sigurd, Sundell, Janne, Syvänperä, Ilkka, Vuorenmaa, Silja Kaarina, Ylönen, Jari, Vesterinen, Eero J., Lilley, Thomas M.
• Other Authors: Finnish Museum of Natural History, Helsinki Institute of Sustainability Science (HELSUS), Faculty Common Matters (Faculty of Biology and Environmental Sciences), Zoology, Tvärminne Zoological Station, Biological stations, Lammi Biological Station, Hyytiälän metsäasema
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2023
• Subjects: 1181 Ecology; evolutionary biology; acoustic monitoring; bats; long-term monitoring; macroecology; spatial ecology; spatio-temporal patterns; Pipistrellus nathusii
• Online Access: http://hdl.handle.net/10138/357362

The distribution ranges and spatio-temporal patterns in the occurrence and activity of boreal bats are yet largely unknown due to their cryptic lifestyle and lack of suitable and efficient study methods. We approached the issue by establishing a permanent passive-acoustic sampling setup spanning the area of Finland to gain an understanding on how latitude affects bat species composition and activity patterns in northern Europe. The recorded bat calls were semi-automatically identified for three target taxa; Myotis spp., Eptesicus nilssonii or Pipistrellus nathusii and the seasonal activity patterns were modeled for each taxa across the seven sampling years (2015–2021). We found an increase in activity since 2015 for E. nilssonii and Myotis spp. For E. nilssonii and Myotis spp. we found significant latitude -dependent seasonal activity patterns, where seasonal variation in patterns appeared stronger in the north. Over the years, activity of P. nathusii increased during activity peak in June and late season but decreased in mid season. We found the passive-acoustic monitoring network to be an effective and cost-efficient method for gathering bat activity data to analyze spatio-temporal patterns. Long-term data on the composition and dynamics of bat communities facilitates better estimates of abundances and population trend directions for conservation purposes and predicting the effects of climate change. Peer reviewed