Abstract. A key challenge of the ecosystem approach to fisheries management is to sustain viable populations of largebodied less-productive vulnerable elasmobranchs that are the by-catch of fisheries that target more productive species. The North Sea population of the thornback ray (Raja clavata) is now mainly confined to the Thames Estuary and surrounding SW North Sea, which is subject to a flatfish trawl fishery. We explored the relative effectiveness of seasonal closures versus size-based landing restrictions using a four-season age-structured model. More than a third of adult thornback rays are currently removed by fishing each year, and without effective management, a further 90% decline within 30 years is likely. A three-season closure of the Thames Estuary was the shortest closure that ensured thornback ray recovery and minimal loss of fishery yield. Minimum and maximum landing size restrictions are nearly as effective at recovering thornback rays but less so at improving yield. While long seasonal closures and full marine protected areas are more effective at ensuring the recovery of thornback rays, length restrictions may be simpler to implement under the current institutional framework and may have less impact on the multispecies trawl fisheries operating in the area.

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The Ecosystem Approach (EA) to environmental management aims to enhance human well-being within a linked social and ecological system, through protecting the delivery of benefits and services to society from ecosystems in the face of external pressures such as climate change. However, our lack of understanding of the linkages between the human and natural components of ecosystems inhibits the implementation of the EA for policy decision-making. Coastal wetland systems provide many benefits and ecosystem services to humans, including nutrient recycling, climate and water quality regulation, timber, fuel and fibre, but they are under considerable threat from population pressure and climate change. In this chapter, we review the ecosystem services provided by coastal wetlands, and the threats to these services. We then present a new integrative conceptual framework to underpin the EA. The framework is divided into three sub-systems: one relating to ecosystem functions, one to ecosystem services, and one to social development and well-being. The pathways linking these sub-systems represent transfers of state, for example, ecosystem functions being transferred into ecosystem services, or ecosystem services being transferred into benefits. The focus of our approach is on enhancing the magnitude and efficiency of these transfers, by introducing or making use of any existing catalysts and overcoming any constraints in the system. The framework represents a dynamic system for implementing the EA in which interventions can be planned and managed in an adaptive way.