The Parcani limestone mine—a new bat (Mammalia: Chiroptera) roosting site of major importance in the Republic of Moldova

Limestone mines are the most important underground roosts for bat species in the Republic of Moldova. The aim of the paper was to first study the bat fauna of a newly registered roosting site—the limestone mine near Parcani, Soldanesti district, in the north of Moldova, in order to elucidate the diversity of bats in various phenological periods and to highlight the importance of this roost in preserving chiropteran diversity. Field studies were carried out in 2023–2024 in different seasons, according to standard methods of bat monitoring in underground roosts, in order to reveal the changes in the bat community structure thorough the year. The species diversity was relatively high, with 10 bat species recorded during the study period: Rhinolophus hipposideros, Myotis blythii, M. nattereri, M. daubentonii, M. dasycneme, M. bechsteinii, M. mystacinus, Barbastella barbastellus, Plecotus auritus,and Plecotus austriacus. The structure of the bat community was different depending on the season. The highest diversity and largest number of individuals were recorded in the hibernation period, when Myotis blythii was the dominant species representing over 80% of the whole bat community. During the summer season, the diversity and number were the lowest, the dominant species was again M. blythii (55.1%), followed by M. daubentonii (20.4%) and M. dasycneme (14.3%). During the breeding season, the diversity and number increased significantly; M. daubentonii and M. blythii were dominant representing more than 90% of the bat community. The Parcani mine is an important roosting site for many bat species, especially in the breeding and hibernation periods. The registered hibernating colony of M. blythii was the largest among all the known colonies in underground roosts of Moldova. The critically endangered species in Moldova—M. nattereri, M. bechsteinii, and B. barbastellus—were registered in the cold period. For M. nattereri and B. barbastellus, it is the second record locality in the territory of the republic. All species recorded in the Parcani mine are protected at national level in Moldova and in neighbouring countries, while the species Myotis blythii, M. dasycneme, M. bechsteinii, Barbastella barbastellus, and Plecotus austriacus are protected at a European level.