The ecologists currently performing sample fish catches in Greifenstein are astonished. Each fish that wants to use the new ladder has to pass through the mobile fish trap. The trap is emptied daily. Most recently an impressive wels catfish with a length of 125 cm was in it, and this just two months after the official opening.
The amount is remarkable as well: 1364 fish of 39 species have been caught so far. Fish 10 cm and longer get a chip implanted for research purposes. This "tag" helps the ecologists study the fish’s migratory movements. Where the fish has just swum past, can be followed online. At the same time, the system is compatible with other projects, so that fish are recorded at the Greifenstein power plant that have for example been marked at the fish bypass in Nussdorf on the Danube Canal.
More than 50 fish species are native to the Danube. More than half of these have already been registered in the Greifenstein fish bypass. These even include rare species such as vimba, common zingel, striped ruffe and Danube roach. A total of 10,000 chips were prepared. An analysis of the data es expected to be possible in the fall.
Partners in the LIFE+ Network Danube project
The Greifenstein fish bypass is part of the "Network Danube". In 2011, VERBUND started the LIFE+ "Network Danube" project, which aimed to create connectivity in selected stretches of the Danube and to implement special structural measures in head of reservoir areas in the form of gravel banks, islands and side arms. In the coming years, and with a total expenditure of approximately 25 million euros and six financing partners (EU, Ministry of Sustainability and Tourism, the provincial governments of Upper and Lower Austria, and the Fisheries Associations of Upper and Lower Austria), VERBUND will improve the fish fauna of four Natura 2000 areas and their tributary systems.