Bioacoustics of Vespertilio murinus

We found breeding of the species only in two localities in the northwest of the study region with one localised maternity roost in the attic space (Annex). In the northeast of the region, in the Chernobyl Exclusion Zone, Gaschak et al. (2009; 2013) regularly recorded V. murinus during the breeding season, in 2007–2013: individuals of this species there comprised 5 % of all netted bats. In other parts of the study region, during the breeding season, the species is almost absent. Summer, exactly dated, observations of the species, there, are presented by single specimens with no breeding females or juveniles among them (e. g. Bilushenko, 2016 ; Ruzhilenko et al., 1998 ; Godlevska, 2012; 2015). In previous publications, there are mentions of maternity colonies in two localities of the ZFS-subregion: one, in a hollow oak in southern vicinities of Kyiv ( Charlemagne, 1933 ); the second, two colonies in hollow trees in Cherkasy Region ( Sologor, 1973 ). Taking into account the absence of any other records of maternity colonies in the ZFS- and Dniester subregions, both in past and present, we presume that mentioned records might concern colonies of Nyctalus leisleri , the species which is similar by size with V. murinus and which, in Ukraine , typically roosts in trees (e. g. Vlaschenko, 2009 ; Godlevska & Rebrov, 2018 ; Annex). Misidentification between these two species occurs even now (L. Godlevska, comm.). Since 1998, V. murinus is recorded regularly in autumn and winter in large settlements, mostly in districts of multi-storey buildings, where parti-coloured bats are regularly found in inner rooms, at the outside surface of buildings or on the ground, in particular in Kyiv . Inside such districts, the autumn display song of males of V. murinus is recorded as well ( Godlevska, 2013 a ; 2015; Annex).The current regular winter occurrence of V.murinus in the region evidently indicates another case of expansion of the bat winter range ( Godlevska, 2013 a ). Noteworthy that the described seasonal dynamics of the species occurrence is similar to that at the adjacent territories to the east from the Dnipro River ( Godlevska, Rebrov, 2018 ): the breeding is known only in the northernmost part, summer records are single, and in winter parti-coloured bats are found in settlements.