FISH COMMUNITY OF THE LOWER REGULATED STRETCH OF THE RIVER MORAVA, CZECH-REPUBLIC

The River Morava (a tributary to the Danube) between the town of Hodon in and the river's confluence with the River Dyje has been channelised , the main channel being totally isolated from its flood plain. The pr esent study describes fish community structure 10 years after completi on of regulation. Species richness and species diversity depended main ly on the connectivity of the regulated section with a more natural se ction below the studied stretch. The bitterling (Rhodeus sericeus), bl eak (Alburnus alburnus), gudgeon (Gobio gobio), chub (Leuciscus cephal us), roach (Rutilus rutilus) and Gobio albipinnatus were the most abun dant species in all sections of regulated main channel, with phytophil ous species occurring in very low densities.