Staff directory
Patricia Mergen
Biology
Invertebrates
Invertebrates
Publication details
Mergen, P. 2002. Distribution spatio-temporelle des communautés ichtyologiques dans les lacs de barrage de Nisramont (Belgique) et d'Esch-sur-Sûre (Grand-Duché du Luxembourg). Series ‘Dissertation Doctorale, Facultés Universitaires Notre-Dame de la Paix. Namur’. Namur : Presses Universitaires de Namur. 416 + annexes p. (PR) ISBN: 2-87037-370-8.
Book
The aim of this study was the characterisation of the fish assemblages in reservoir lakes, in order to place them with regard to the ichthyologic communities in running and standing waters. The study areas were the Nisramont Reservoir in the Belgian Ardennes and the Esch-sur-Sûre Reservoir in the Grand Ducal Ösling. Our investigations were focused on one year and older fishes as well in the pelagic zone as in the littoral zone, and the young-of-the-year in the littoral zone only. For this purpose, we designed a standard sampling protocol combining vertical gillnetting in the pelagic zone and electric fishing in the littoral zone. Specific composition is typical of eutrophicated standing waters. On an inter-annual basis, the fish assemblages presented a certain stability in the pelagic zone, but an instability in the littoral zone. Concerning the young-of-the-year, we were able to separate typical riverine species (Gobio gobio L., Leuciscus leuciscus L. …) from lake species (Abramis brama L., Rutilus rutilus L. …) and to show the importance on their repartition patterns of the temporal factor, the position of the station in the lake and some environmental factors such as the temperature of the water, the pH and the presence of vegetation. Our study reinforces the hypothesis that reservoir lakes are environmental hybrids between standing and running waters.