Winter aggregations of bats in cave-type shelters of Ternopil Prydnisteria: surveys of 2021–2024

Data on species composition and abundance of bats during hibernation surveyed in the winter of 2024 in 12 cave-type shelters are presented. During these studies, 7 species of bats were found in hibernation. As in previous years, the most numerous species was the lesser horseshoe bat. Another 3 species, the greater mouse-eared bat, Daubenton's bat, and the brown long-eared bat were found in several shelters in small numbers. Three species (Myotis nattereri, M. mystacinus, and Plecotus austriacus) were found in one individual each. Two species (Barbastella barbastellus and Eptesicus serotinus), which were found during the 2021 survey, were not found in 2024. A comparison of the 2021 and 2024 survey data shows a stable abundance of winter aggregations of the thermophilic lesser horseshoe bat and a reduction in the number of cold-loving species, which is likely caused by a stable trend of increasing winter temperatures.