Buysse, D.

Coeck, J.

Mouton, A.

Stevens, M.

Van den Neucker, T.

Open Marine Archive

 - 69 -  
Adjusted barrier management to improve glass eel migration at an 
estuarine barrier 
Mouton Ans M., David Buysse, Maarten Stevens, Tom Van den Neucker and Johan Coeck 
Research Institute for Nature and Forest (INBO), Kliniekstraat 25, 1070 Brussels, Belgium 
E-mail: Ans.Mouton@INBO.be 
European eel populations (Anguilla anguilla L.) have declined dramatically during the last decades 
and are now some of the most critically endangered fish populations in Europe. The limitation of 
upstream migration of glass eels is considered to be one of the key factors reducing eel 
populations. This paper presents the results of a study on the migration of glass eels and options to 
improve eel passage at a tidal barrier complex at the mouth of the River Yser, Flanders, Belgium. 
Glass eels were sampled during tidal rise with stow nets and lift nets to analyse their distribution 
over the study area, while a fyke net was used to evaluate the impact of limited barrier opening on 
glass eel migration. Support-vector machine-based analysis of the lift net data indicated that 
migrating glass eels are attracted by the freshwater flow leaking from the barriers, whereas other 
variables such as the sampling location only had a weak impact on the glass eel density. Limited 
barrier opening during tidal rise appeared to be a cost-efficient and effective mitigation option to 
improve upstream glass eel migration, without significant intrusion of sea water. Adjusted barrier 
management could often be implemented and applied on numerous tidal barriers. Therefore the 
results of this paper are of interest to a wide range of river managers and stakeholders and may 
contribute to the conservation of many eel populations. Further research could maximise the 
number of migrating glass eel and reveal the impact of this approach on the upstream eel 
population. 
 
 
 


Adjusted barrier management to improve glass eel migration at an estuarine barrier

Abstract

Similar works

Full text

Available Versions

Open Marine Archive