Shift change in the cold: female Daubenton's bats share scarce feeding grounds at the edge of their range

A research team from the University of Naples Federico II, the Museum für Naturkunde Berlin and several international partner institutions tracked female Daubenton’s bats (Myotis daubentonii) using radio telemetryin newly colonised mountainous regions of the Italian Apennines. Here, female Daubenton’s bats take turns hunting rather than hunting side by side at the same time. A study published in the journal ‘Global Ecology and Conservation’ shows that this temporal separation helps the bats avoid competition and may be crucial to their survival at the cold edge of a climate-driven range expansion.

A research team from the University of Naples Federico II, the Museum of Natural History in Berlin and several international partner institutions tracked female Daubenton’s bats (Myotis daubentonii) using radio telemetry along a 10-kilometre stretch of the upper reaches of the River Sangro in the Abruzzo, Lazio and Molise National Park in central Italy. This mountainous river landscape, situated between approximately 800 and 1,100 metres above sea level, has only recently been colonised by reproductively active females, as the species is shifting its range uphill in response to global warming.

“Our study shows that female Daubenton’s bats, at the forefront of climate change, are not only migrating uphill but also temporally partitioning their habitat,” says lead author Chiara Belli of the University of Naples Federico II and the Museum für Naturkunde Berlin. “Instead of foraging together, the females take turns. Although they visit the same productive feeding sites, they rarely do so at the same time.” The team found that the females concentrated their activity on a few preferred hunting grounds. Most bats repeatedly used only one to five feeding sites and spent at least 75 per cent of their hunting time at their two most frequently visited locations – clear evidence of strong site fidelity and familiarity with specific feeding sites. Simultaneous use of the same feeding site was rare. Tagged females were observed taking turns over the same river sections, with the flight paths of individual bats differing precisely in timing.

“At these high-altitude locations, the supply of insects is limited and the nights can be cold, which is particularly problematic for lactating females with high energy requirements,” explains lead author Danilo Russo from the University of Naples Federico II and the Museum für Naturkunde Berlin. “By staggering their visits and repeatedly returning to familiar areas, the females appear to reduce costly competition and make the best of this challenging environment.”

The dense riparian vegetation along the Sangro River not only provides roosting and foraging sites but also serves as a green corridor, enabling the females to colonise higher elevations. Previous work by the same team showed that this forested river corridor was essential for the water bat’s expansion into higher elevations; the new study now demonstrates how this behaviour fine-tunes that expansion by potentially reducing competition at the edge of the range.

Publication: Riparian bats temporally partition foraging at the cold edge of an uphill climate-driven area expansion (2026) Belli C, Cistrone L, Knörnschild M, Sestovic B, Ekklisiarchos I, Aldasoro M, Borgonovo C, Migliaresi I, Di Domenico M, Ratcliffe J, Russo D. Global Ecology and Conservation, e04129 https://doi.org/10.1016/j.gecco.2026.e04129