Ectoparasites of the bats from karst caves of the nature reserve «Ichalkovsky Bor» (Nizhny Novgorod Region)

The fauna of parasitic mites of bats from the karst caves in the region of the Volga Upland was studied in 2004–2005. Six species of bats such as Daubenton’s water bat, Brandt’s bat, whiskered bat, pond bat, northern bat and long-eared bat were examined. 18 species of arthropods were detected, among them there are gamasid mites (10 species) and harvest mites (2 species). Leptotrombidium russicum (Oud., 1902) and Myotrombicula sp. were found for the first time in Central Russia. Spinturnix acuminatus (Koch, 1836), Steatonyssus spinosus (Willmann, 1936), Steatonyssus periblepharus (Kolenati, 1858), Macronyssus flavus (Kolenati, 1856) turned out to be the main group of parasites in this study. As for the insects flies of the family Nycteribiidae and fleas of the family Ischnopsyllidae were found. The cluster analysis of ectoparasite fauna has showed that they are more or less evenly distributed among all members of mixed colonies of bats, while there is no violation of specificity in the choice of hosts. Low values of the Berger-Parker index marked a lack of competition between species, which indicates the stability of parasitic communities formed on bats in mixed colonies and in natural habitats. This fact indicates a complex relationship between the parasites in the community on the one hand, and long-term existence of the community on the other hand. This, in its turn, shows that in long-evolving communities competitive relationships between parasites are obliterated, which gives them stability. Herewith the bat colony is used as an integral whole, although some parasitic species prefer certain types of hosts.