Present address: Laboratoire d'Ecologie Animale, Faculté des Sciences, Université d'Angers Belle-Beille, 49045 Angers, France.
Spatial organisation of European eel (Anguilla anguilla L.) in a small catchment
Article first published online: 10 NOV 2003
Ecology of Freshwater Fish
Volume 12, Issue 4, pages 254–264, December 2003
How to Cite
Laffaille, P., Feunteun, E., Baisez, A., Robinet, T., Acou, A., Legault, A. and Lek, S. (2003), Spatial organisation of European eel (Anguilla anguilla L.) in a small catchment. Ecology of Freshwater Fish, 12: 254–264. doi: 10.1046/j.1600-0633.2003.00021.x
- Issue published online: 10 NOV 2003
- Article first published online: 10 NOV 2003
- Accepted for publication April 30, 2003
- Anguilla anguilla;
- spatial organization;
- artificial neural networks;
Abstract – Modelling-governing patterns of European eel (Anguilla anguilla L.) distribution of four eel size classes (<150, 150–300, 300–450 and >450 mm) in the Frémur basin (northwest France) was done using artificial neural network (ANN) techniques and ecological profiles. Our results demonstrate the high predictive power of the ANN models. Some macro- and microscale factors, such as distance from the sea, depth and flow velocity, have the most significant influence on the models. Influence of distance from the sea appears to be very different from the spatial organisation usually described in river systems. In fact, the general tendencies of total eel densities according to the distance from the sea showed that densities increase weakly upstream. Another outcome was the variations in habitat preference according to the eel size, even if this species is spread over practically every type of microhabitat. Small eels were mainly found in shallow habitats with strong abundance of aquatic vegetation, whereas large eels tend to be found in intermediate to high depth with small to intermediate abundance of aquatic vegetation. Finally, we hypothesise that European eels change behaviour and microhabitat characteristic preference around a size of 300 mm.