Long-term evolution of fish communities in European mountainous rivers: past log driving effects, river management and species introduction (Salzach River, Danube)
Haidvogl G. ; Pont, D. ; Dolak, H. ; Hohensinner, S.
Type de document
Article de revue scientifique à comité de lecture
Affiliation de l'auteur
INSTITUTE OF HYDROBIOLOGY AND AQUATIC ECOSYSTEM MANAGEMENT UNIVERSITY OF NATURAL RESOURCES AND LIFE SCIENCES VIENNA AUT ; IRSTEA ANTONY UR HBAN FRA ; INSTITUTE OF HYDROBIOLOGY AND AQUATIC ECOSYSTEM MANAGEMENT UNIVERSITY OF NATURAL RESOURCES AND LIFE SCIENCES VIENNA AUT ; INSTITUTE OF HYDROBIOLOGY AND AQUATIC ECOSYSTEM MANAGEMENT UNIVERSITY OF NATURAL RESOURCES AND LIFE SCIENCES VIENNA AUT
Résumé / Abstract
Using historical sources from the turn of the 19th to the 20th century, we investigated the long-term evolution of the fish community in a mountainous river network and the influence of different human uses and management measures. Within the alpine Salzach catchment, historical presence was reconstructed for 26 fish species, abundance classes for 19 species. Due to channelization, flood protection and dam erections, the spatial distribution of fish species was reduced during the 20th century. Many rheophilic and eurytopic fish species historically inhabited river reaches along a wide longitudinal profile and were present in more upstream river reaches than nowadays. The decrease of species diversity in the headwater sections is a consequence of lost lateral connectivity. Strongest effects are reported for sensitive species requiring different habitat types during their life cycles (especially pike, nase, Danube Salmon). One of the most important shifts from the historical fish community to the present one is due to deliberate introduction of fish species for fisheries. Rainbow trout and brook trout, absent at the end of the 19th century, represent nowadays up to 29% of the total number of fish occurrences. In contrast, log driving, one of the most common historical pressures in European mountainous rivers did not show significant negative effects on the historical fish community. This result strongly differs from the severe impacts of log driving and deforestation demonstrated for recent the time, and could be related to the change in log driving practices during the 20th century and to the high societal value of fisheries before the industrialization period. In general, our result could be considered for a large number of European mountainous rivers. They highlight the interest of such detailed historical studies for the understanding of the long-term evolution of fish communities, their present functioning and future river management to restore fish biodiversity.
Aquatic Sciences, vol. 77, p. 395 - 410