Developing a science base for implementation of the ecosystem approach to fisheries in South Africa

摘要

South Africa's commitment to implementation of the ecosystem approach to fishing (EAF) requires a solid scientific basis comprised of a toolkit assembled through concerted efforts from which management measures can be carefully considered and put into place. A series of workshops was held to assist in the identification of issues in South Africa's key fisheries that are cause for concern and may have EAF implications. Several of these issues were addressed under various projects. Food-web studies have been undertaken and models have been constructed of the changes in the structure and functioning of the Southern Benguela upwelling system. The combined effects of fishing and environmental change on South African fisheries have been examined using various observation-based and modelling methods. These are contributing to assessment of changes at multiple spatial and temporal scales, from the impact of pelagic fishing in key foraging areas of critically-dependent predators, to impacts of demersal trawls on the benthos and demersal fish assemblages, to decadal-scale dynamics, and global comparative classifications of ecosystem status. To address some of the EAF issues, practical implementation measures are being developed and applied in collaboration with stakeholders. Stakeholders are also actively involved in the process leading to development of indicators to address the human dimensions of EAF, and knowledge-based systems are being developed as decision support tools. Future priorities for South African EAF research will include placing more emphasis on conservation and biodiversity aspects, linking of environ-mental/oceanographic knowledge to management objectives, spatial aspects, as well as increased focus on the human dimension and transdisciplinary approaches. Indicators are a promising means of synthesizing multi-disciplinary information for consideration in the management process, providing measures of anthropogenic (including fishing) pressures including social and economic pressures, in combination with environmental drivers, and providing a means of assessing how these affect the Benguela ecosystem. Respectful scientific collaboration will be required to bridge the gap between classical single-species fisheries management approaches and broader ecosystem approaches.