Recruitment study on North Sea fish stocks

Recruitment to several of the ecologically and commercially important fish stocks in the North Sea has been strongly reduced during the recent years, causing concern for fishers, managers and scientists alike. This includes herring, cod, haddock, sandeel, and Norway pout. We propose an applied and multidisciplinary study to explain the recent series of poor recruitment to these five target stocks and enhance the understanding of the mechanisms behind. Our study is novel for several reasons. A) The species considered span completely different life histories, different niches in the ecosystem, different horizontal and vertical distributions and are exploited by different fishing fleets. Such a cross species study has never been tried in the North Sea before and seldom elsewhere. B) This proposal takes a broad integrated approach - understanding that processes working on the individual fish occur in a space and time that either does or does not overlap with prey, predators and favourable physical conditions. C) We will utilize that state of the art has progressed substantially in terms of hydrographic modelling, time series analysis, spatial overlap modelling, and the integration of individual models to population level. D) The proposed project will bring to gether a multidisciplinary team with expertise from statistical and numerical modelling to hydrography, to phyto- and zooplankton, to fish ecology, to stock assessors and management strategy evaluators. Recent recruitment studies have succeeded in the B arents and Baltic Seas and it is now timely to apply the methods used in these seas to the North Sea. By enhancing the knowledge on recruitment to major North Sea fish stocks, the project will provide a research based foundation for long-term integrated m anagement and harvesting of important marine resources. The project should work towards strengthening Norway?s position among the world-leaders in marine ecosystem based research.