7. Annex 2 – Review of Theoretical Community Ecology: Implications for Marine Communities

Recent years have witnessed a shift in emphasis in the underlying objectives of fisheries management in the North Sea. Whilst the need to conserve individual stocks at sustainable and economically viable levels is still clearly a major priority, managers are now being asked to adopt a broader ecosystem approach to managing fisheries. The political impetus behind this change in attitude has largely been provided by the “North Sea Ministerial Conferences”, five of which, along with a further two “Intermediate Ministerial Meetings”, have occurred over the period 1982 to 2002. These ministerial conferences were in turn influenced by the political commitments made to conventions such as the “Convention on Biological Diversity” (CBD) and the “Convention for the Protection of the Marine Environment of the North-East Atlantic” (OSPAR, because it combined two the two earlier Oslo and Paris Commissions). With the inclusion of Annex V in the OSPAR Convention, OSPAR was considered by ministers attending the fourth North Sea Ministerial Conference at Esbjerg in 1995 to be the competent authority with primary responsibility for the development of the ecosystem approach to management. At a workshop at Scheveningen in September 1999, a basic template for an ecosystem approach to management was proposed. Ten “issues” were identified for which Ecological Quality Objectives (EcoQOs) would be set (figure 7.1.1). Ecological Quality (EcoQ) was defined as the “Ecological quality of ecosystems is an overall expression of the structure and function of the aquatic systems, taking into account the biological community and natural physiographic, geographic and climatic factors as well as physical and chemical conditions including those resulting from human activities”. EcoQOs were defined as “the desired level of EcoQ relative to a reference level” where reference levels were defined as “the level of the EcoQ where the anthropogenic influence on the ecological system is minimal” (Skjoldal et al. 1999). Issues 1 to 4 were intended primarily to involve EcoQOs based at the level of individual species. Thus conservation objectives currently used in the single species assessments and management of commercial fish stocks could be carried over as EcoQOs for Issue 1. When addressing Issues 5 to 7, however, the situation becomes more complicated. For these issues, it was anticipated that EcoQOs would be directed towards multi-species, community, or assemblage attributes and this has initiated a “hunt” for appropriate indicators of community or assemblage health (Frid 2003).