Abstract
With the rapid upscaling of offshore wind farms (OWF’s) in the North Sea, pressures are mounting on other users, such as fisheries. Successful increase of OWF development and exploitation requires integration in the environment, in terms of ecology and multi-use. This poses an innovation challenge for multiple parties. OWF operators need to minimise the risks involved in multi-use. Spatial design of OWF’s might need to be adapted. Fisheries need knowledge on alternative species with commercial potential and innovation on catch methods. Amongst others the passive low-impact fisheries of European lobster (Homarus gammarus) and brown crab (Cancer pagurus) have been proposed as excellent opportunities (Linley et al., 2007). To that extent a TKI tender has been awarded and the project Win-Wind on enabling this type of fisheries has commenced. The current research is part of phase 1 “preconditions for a demonstration pilot”: generating the essential knowledge to proceed. Subsequent future phases comprise phase 2 “implementation pilot” and phase 3 “business implementation and upscaling”. This report on the ecology of brown crabs is a product of phase 1. Here we focus on the ecologic and sustainable feasibility of passive low impact brown crab fisheries by describing the general ecology of brown crabs in the North Sea and around Dutch OWF’s in particular. It is currently unknown whether low impact brown crab fishery in offshore wind farms in the North Sea is feasible from an ecological point of view. This desk study provides an overview of current knowledge on brown crab ecology and a base document in order to create insight in harvest potential of brown crab (Cancer pagurus) within Dutch offshore wind farms.