Session A2: Like Shooting Fish in a Barrel: Migratory Behavior of Fish at Intertidal Fish Passes in Dutch Wadden Sea

• Main Author: Huisman, Jeroen
• Format: Text
• Language: unknown
• Published: ScholarWorks@UMass Amherst 2015
• Subjects: Aquaculture and Fisheries; Hydraulic Engineering; Anguilla anguilla
• Online Access: https://scholarworks.umass.edu/fishpassage_conference/2015/June22/14; https://scholarworks.umass.edu/cgi/viewcontent.cgi?article=1777&context=fishpassage_conference

Abstract: The Wadden Sea is a large intertidal area in the Northwest of Europe and is listed on the UNESCO’s World Heritage List (UNESCO 2009). The tributaries and estuaries in the Dutch part of the Wadden Sea are relatively small and as such have suffered extensive habitat loss and habitat degradation due to empoldering and measures ensuring flood protection e.g. pumping stations, weirs and sluices. The Wadden Sea and its intertidal barriers offer a unique opportunity to investigate migratory behaviour of fish and fish pass functioning with regards to diadromous fish. To facilitate fish migration intertidal fish passes in the Wadden Sea are often designed to temporarily let water in and/or out from tributaries. Combining the temporal aspects of aforementioned fish passes with the temporal spatial behavioural patterns of fish migration is a challenge. How to combine fish pass functioning with the needs of present fish species and different life stages? The intertidal pumping stations Duurswold, de Drie Delfzijlen en de Helsdeur are researched using telemetry. We have used acoustic telemetry (Anguilla anguilla) in order to investigate behaviour and route choice of seaward migrating silver eels. Analyses of data will provide insight in for example delay and route choice. In addition, a number of migrating silver eels have been detected along the Dutch-Belgian coast which raises the question which routes are favoured by silver eels on their way to the Sargassosea and why. At the pumping station “De Helsdeur” we have PIT-tagged a number of three spined sticklebacks to investigate fish pass functioning in relation to intertidal migratory behaviour and interspecies variation of three spined sticklebacks (Gasterosteus acculuatus). Results show that sticklebacks mainly migrate during daylight and at upcoming tides