ABSTRACT. The aim of this work was to identify the current structure, condition, and changes in the species diversity of the ichthyofauna of the Czarna Staszowska (a left-tributary of the Vistula) 36 years following the construction of the Chańcza Reservoir. Fish were caught at six sites on the river with electrofishing up- and downstream from the reservoir. Four species that had not previously occurred were noted in the river: ruffe, ide, Ukrainian lamprey, and pikeperch. Currently, the following formerly occurring species are not noted: common barbel, three-spined stickleback, carp, bream, tench, European weather loach, common nase, and common bleak. The reasons for the disappearances of many fish species and changes in ichthyofauna diversity, trophic structure, and fish condition are all discussed in the context of increasing anthropogenic pressure in the Czarna Staszowska drainage basin.
Keywords: electrofishing, Chańcza Dam Reservoir, ichthyofauna condition
Przyjęto po recenzji 9.06.2015 r.