Sterlets with active tags in Nationalpark Donauauen
With the aim to gather information about habitat choice and migrations of the sterlet 32 fish were tagged and released in the Danube in March 2020. With the use of acoustic telemetry the fish are tracked via fixed hydrophones and mobile tracking between the hydropower plant Freudenau near Vienna, along the free flowing stretch of the Nationalpark Donauauen to the impoundment section of Gabcikovo below Bratislava. A tag life of one year guarantees coverage of all seasons and therefore the opportunity to get insights into the sterlets’ different phases of its annual cycle lives. We aim for identifying habitats the sterlet uses for feeding, overwintering and even for reproduction.
Since their release we could encounter 24 tagged fish. Some in the vicinity of their release point others already migrated many kilometers. These results already gave us initial information but above all the successful beginning bolsters up for more exciting findings.