Checking of Bats Wintering Colonies in Georgia
Field surveys to check several caves were conducted from the 10th of December through the 21st of December 2022. The main goal of this survey was to check those caves where wintering colonies were recorded during previous years. Also, we checked some caves for the first time on the existence of bat wintering colonies. In total, six caves were checked for winter colonies located in different municipalities of Georgia (Map 1).
All caves are located in the karstic outcrops of Western Georgia. Bats were recorded in four caves excepting of caves Kidobana and Vardgora. On the other hand, we were not able to check the whole Cave Vardigora, since it is a big cave with siphonic lakes and areas, where climbing equipment is needed. Cave Melouri – is part of the Imereti Caves Protected Area and it has the status of a Natural Monument. In the winter of 2015, wintering colony of Mediterranean Horseshoe Bat (Rhinolophus euryale) consisting of more than 2000 individuals was recorded. In winter 2022, wintering colony of Mediterranean Horseshoe Bat was not recorded, however wintering colony of Greater Horseshoe Bat (Rhinolophus ferrumequinum) consisting of about 280 individuals was recorded.
Cave Sakishore – There is a wintering colony of Schreibers’ Bent-winged Bat (Miniopterus schreibersii) in this cave. In 2022, we counted about 250 individuals of these species. In March 2016, about 720 individuals of these species were recorded.
- Cave Kidobana – no wintering colony was recorded.
- Cave Vardigora – no wintering colony was recorded.
- Cave Sachinkia – wintering colony of Greater Horseshoe Bat (Rhinolophus ferrumequinum) was recorded: we recorded about 110 individuals of this species.
- Cave Samertskhle klde – in this cave, wintering colony of Greater Horseshoe Bat (Rhinolophus ferrumequinum) was recorded. Also, single individuals of the Blasius’s Horseshoe Bat (Rhinolophus blasii), Lesser Horseshoe Bat (Rhinolophus hipposideros), Schreibers’ Bent-winged Bat (Miniopterus schreibersii) and Lesser mouse-eared bat (Myotis blythii) were recorded. It should be highlighted that the cave Samertskhle klde is the only cave known in Georgia where bats inhabit all year around. In this cave, we have wintering colony as well as a mixed maternity colony consisting of two species: Schreibers’ Bent-winged Bat (Miniopterus schreibersii) and Lesser mouse-eared bat (Myotis blythii). By our estimation, this mixed maternity colony could be the largest in Georgia, with a number of more than 8000 individuals.