Migration of European silver eel in an anthropogenically impacted wetland area in Belgium

Despite substantial efforts to restore the European eel (Anguilla anguilla L.) population in the last decade, recovery fails to appear. Migration barriers are believed to play a significant role in this, especially in anthropogenically impacted water bodies. In Belgium, for instance, eel has been un...

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Bibliographic Details
Main Authors: Verhelst, Pieterjan, Mouton, Ans, Buysse, David, Pauwels, Ine, Coeck, Johan
Format: Conference Object
Language:English
Published: 2015
Subjects:
Online Access:https://biblio.ugent.be/publication/8527836
http://hdl.handle.net/1854/LU-8527836
Description
Summary:Despite substantial efforts to restore the European eel (Anguilla anguilla L.) population in the last decade, recovery fails to appear. Migration barriers are believed to play a significant role in this, especially in anthropogenically impacted water bodies. In Belgium, for instance, eel has been unable to reach a vast proportion of the highly suitable lowland river habitats for decades. Consequently, insight into eel migration is needed and therefore we analysed eel behaviour by acoustic telemetry in a polder area that was a historical eel hotspot but has now been blocked by several migration barriers. Between July and October 2012 we tagged 99 eel and observed their behaviour until July 2013. Eel behaviour was linked to environmental conditions (water temperature, habitat conditions, flow), biotic conditions (silvering stage) and migration barriers. Several behaviour types were observed: homing, searching, delay and migration. Based on the results, several mitigation options could be compared and water management in the study area could be optimised to facilitate eel migration. These findings are also of interest in other anthropogenically affected lowland areas with similar migration barriers like weirs and pumping stations.