Conceptual and practical advances in fish stock delineation

The fish stock delineation concept has now evolved informed by knowledge affordable from a variety of new genetic and geochemical life cycle tracers in addition to traditional morphometric, parasitological and life history trait approaches. These can be coupled with better definition of oceanographic processes enhanced by GIS-related modelling tools. Population structure and stock delineation are central considerations for scientific assessment and strategic management in Fishery Sciences and have to be addressed from a meta-population perspective where complementary technical approaches meet to enable the best resolving power. Evaluation of analytical tools allows assessing the minimum amount of information needed to properly delineate stock units. Single technical approaches are insufficient to delineate complex stock structures. There is a need to harness the full power of complementary and synergistic interdisciplinary approaches and tools; such an approach remains underused. In this special issue we consider scientific and technical advances in some research disciplines pertinent in fish stock delineation (i.e. Genetics, Ecology, Parasitology, Chemistry, Oceanography, Mathematics and Economics). In this introductory chapter we identify modelling challenges and research needs required to improve fishery assessment and management efficiency by better delineation of stocks.