Monster Seminar JAM - How do human pressures influence the European Fish Fauna?
Rafaela Shinegger, Visiting researcher; Doctoral candidate, Dept. Water Atmosphere and Environment, Institute of Hydrobiology and Aquatic Ecosystem
Most European rivers are affected by different types of human pressures. We analysed pressure variables of 4 different pressure groups, i.e. hydrology, morphology, water quality and connectivity to detect spatial patterns, relationships and interactions between pressures, fish metrics and natural environment at the European scale. Based on literature and expert knowledge important pressures as well as fish sampling data and environmental data were identified and collected within the EU-project EFI+ in 14 countries at about 10 000 sites in Europe. In 90% of the catchments analysed fish migration was interrupted. Pressure analysis showed alterations in 55% for water quality pressures, 40% for hydrology, 37% for morphology and 34% for connectivity. In terms of combined pressure, 24% of sites are affected by single pressures, 22% by double pressures, 19% by triple pressures and 12% by four pressure groups. Only 23% of sites are not/slightly affected. In the reaction of the fish fauna, rheophilic, intolerant and potamodromous fish metrics showed strongest results, as they were able to discriminate between different pressure types and combinations. As the reaction of fish metrics often differed by natural environment, a more detailed view on eco region or catchment level was necessary to detect more specific reactions. Finally, our results clearly show that European rivers are multi-impacted and that the fish fauna shows strong reaction upon those impacts
Date and Time:
May 26, 2011,
11:00 am - 12:00 pm