SEAwise Report on Key Drivers and Impacts of Changes in Spatial Distribution of Fisheries and Fished Stocks

An ecosystem approach to fisheries management requires the consideration of spatially explicit management measures and other impacts on species and the links between the distribution of fished species, their surrounding environment and productivity. Quantification of the spatial aspects of fisheries and ecology of commercially fished stocks may improve the accuracy of the predicted changes in fish productivity, fisheries yield and costs, benefits and selectivity.

To provide a knowledge base for spatially explicit considerations, SEAwise consulted stakeholders throughout Europe and conducted a systematic review of the scientific literature. As a first step, engagement with relevant stakeholder groups in each Case Study identified key issues of relevance to spatial management.

The input from this stakeholder consultation was supplemented by a systematic literature review with careful consideration of the objectives, search terms, inclusion/exclusion criteria, the method for data/knowledge extraction and ultimately how these data and knowledge will be used. The purpose of the task was to quantify the key drivers and pressures behind the changes occurring in commercial fish stocks and fisheries distribution that have a spatially explicit content, map the relevant existing scientific knowledge and provide input to the subsequent SEAwise tasks.

The words identified by the stakeholders consulted focused on factors causing changes to the distribution of commercial fish/shellfish (climate change, MPAs, species interactions, pollution, habitats and invasive species) and fisheries (windfarms, MPAs, Marine spatial planning) as well as the other human impacts.

The systematic review extracted data from 331 papers. The most frequently studied topic was the distribution of fish and the region with most papers was the North Sea with about the twice the amount of papers in each of the other regions. The most frequently studied species in the literature were cod, hake and plaice and by far the most frequently studied fisheries was demersal trawl fisheries.

Among the issues identified by stakeholders as key, the effects of environmental conditions on the distribution of fish were particularly well represented in the reviewed material. In contrast, factors determining the distribution of fisheries were almost exclusively studied in trawl fishing in the North Sea and papers on the effect of area restrictions on fish and fisheries were largely restricted to Western waters and the North Sea.

While knowledge on the effects of habitats on species did exist, this was restricted to the Baltic Sea and North Sea and papers addressing this outside these areas were close to non-existent. This points to important areas for future work in SEAwise.