1. Institute for Agricultural and Fisheries Research (ILVO), Ankerstraat 1, 8400 Oostende, Belgium.
2. Ghent University, Marine Biology, Krijgslaan 281-S8, B-9000 Gent, Belgium.
3. Ifremer, B.P. 21105, 44311 Nantes CEDEX 03, France.
4. Université de La Rochelle (Observatoire PELAGIS), 5 allée de l’Océan, 17000 La Rochelle, France.
5. Research Institute for Nature and Forest (INBO), Kliniekstraat 25, 1070 Brussels, Belgium.