Integrating spatial management measures into traditional fishery management systems: the case of the Georges Bank multispecies groundfish fishery

Abstract

Abstract Primary determinants of the productivity of most fisheries are the level of fishing mortality and the age structure of the catch. Constraints on nominal effort or catch and technical measures such as mesh sizes are typically the most effective methods of ensuring productivity and sustainability. Stock assessment models are generally well adapted to assess the biological implications (though less often the economic implications) of these measures. However, the increasing use of spatial management measures such as marine protected areas (MPAs) or seasonal area closures presents new challenges for fishery managers. Assessment models and data collection programs are rarely designed or adaptable for analysis of these measures. Using spatial management measures effectively requires new models and data. Models of Georges Bank groundfish fisheries are presented and used to explore the impacts of area closures in the context of the overall management system. Although the spatial dynamics of the models are highly stylized, they illustrate mechanisms through which area closures can increase productivity and profitability of a spatially heterogeneous multispecies fishery. The utility of taxes to control the distribution of effort is also explored.