Temporary co-existence of aquatic and terrestrial invertebrates in shallow periodically flooded and frozen cave

Abstract

Abstract The effect of specific microclimatic conditions and temporary flooding on terrestrial and aquatic invertebrate community composition as well as on parietal fauna was investigated in a cave located on the Krakow-Wieluń Upland. Studies of the fauna started after partial water retreat from the cave. Microclimate conditions and water chemistry parameters were also investigated. Due to the cave geometry and its size, temperatures recorded during summer were relatively high, whereas almost all its parts were frozen in winter. Temporary cave flooding promoted reproducing populations of Asellus aquaticus, Pseudocandona sarsi and copepods (Diacyclops bicuspidatus, Megacyclops viridis). Completely depigmented (including eyes), slightly, as well as fully pigmented individuals of A. aquaticus were found. Some dipterans started to reproduce in the flooded cave but drying stopped their development. Some taxa typical for terrestrial habitats (Collembola and Acari) and for parietal fauna (spider Meta menardi, moth Triphosa dubitata, dipterans from families Helomyzidae and Mycethophilidae) were not observed. Moreover, cave freezing significantly diminished the number of Culicidae, Oniscus sp., gastropods and Nesticus cellulanus wintering in the cave. The recolonization process was possible due to the cave location at the shallow subsurface and multiple entrances. The diversity of terrestrial invertebrates in the cave is very low as the effect of periodical flooding and freezing.