Designing and evaluating a fish pass at the power plant Villach/Drau

Within an extensive monitoring program the efficiency of a newly developed vertical slot fishway consisting of prefabricated parts is evaluated. Methods applied are: electrofishing, trapping, Radio-telemetry and Pit-tagging. Additonally abiotic data like water temperature, discharge and conductivity are measured. The dominant species expected downstream of the weir are rainbow trout, European grayling, brown trout and burbot. River type specific species like nase and barbel have become rare in the downstream section due to impoundment. Also the Danube salmon, now locally extincted, belonged to the river type specific fish fauna.