Nephrops fleet - optimisation modelling: policy brief

Economic research providing a valuable addition to the evidence base of Scotland’s Nephrops fishery to help inform discussions on the future of fisheries management.

Conclusions and Policy Considerations 

The research has shown that there is potentially an opportunity for economic gains if access to fishing grounds is redistributed between and within the Nephrops creel and trawl fleets. The research provides valuable evidence to guide ongoing discussions on Future Fisheries Management in Scotland, the route through which Marine Scotland will consider evidence from this research to make policy decisions. In doing so, policy will need to take account of a number of factors, some of which are discussed below.

First, the results from the research do not take into account costs to businesses of amending fishing patterns, nor the management and compliance costs associated with any fisheries management designed to achieve what the research identifies as the optimal outcome. The reasons why vessels’ activity in 2017 was not consistent with the optimum identified by the research are likely to be numerous and complex. They could include factors such as: weather, other fisheries management restrictions, perceived gear conflict itself, or other business or personal decisions. Understanding how these factors affect vessel fishing patterns and fishers’ behaviour would be important in devising policies to try and maximise gross value added or employment.

Second, it is unclear whether the optimum outcome identified by this research could be achieved in practice. This research was an exploration of optimisation modelling, which while shown to be feasible includes a number of data and modelling challenges that need to be carefully considered when interpreting the results. While the model and assumptions used have been rigorously tested, consideration may be needed to sense-check these further, and whether modelled changes in some of the fleet segments are feasible let alone desirable. The Future of Fisheries Management discussions would also have to consider what the future policy objectives would be for the Scottish Nephrops fishery. 

Third, economic considerations are only one basis on which Marine Scotland approaches fisheries management. Other factors to consider would be the environmental impacts of the fishery, impacts across supply chains, social impacts, continued access to markets including EU exit impacts, and the impact on prices to changes in the quantity of landings. Further research is required in these areas to build a more complete evidence base. For instance, to maximise gross value added would lead to substantial changes within the creel fleet as well, allocating fishing opportunities to the most efficient, typically larger, creel vessels. This could be to the detriment of smaller scale creel vessels operating on a less commercialised basis but making important contributions to social outcomes to our remote communities.

Fourth, while the research includes around 85% of the Nephrops landings value, there is a need to consider the impact on vessels in other fleet segments more fully. Crucially, the Nephrops fishery does not operate in isolation from other fisheries and interactions with other species needs to be explored further, both in environmental and business terms. Nephrops targeting vessels land other species, and Nephrops may be a by-catch of vessels targeting other species. Impacts on other marine users, including recreational fishers or offshore wind, are also not considered in this report, and would be important factors in any consideration of how best to use Scotland’s marine space. 

Despite the above points, the research indicates potential opportunities to improve economic outcomes within the Scottish Nephrops fishery. Marine Scotland will explore these opportunities as part of the Future of Fisheries Management programme while carefully considering the above points. Marine Scotland is already involved in a number of projects that look to build on several of the evidence gaps identified by the research and that have the scope to test some of the points it identifies. For example, the Scottish Inshore Fisheries Integrated Data System (SIFIDS) project has examined ways to improve data collection within the inshore fleet, which may lay the foundation for more targeted analysis and management in the future, while the Inshore Fisheries Pilots will expand the evidence base around the scope and practical challenges facing local fisheries management. In terms of environmental impacts, Marine Scotland Science are undertaking an evidence review in relation to both the biological stock impacts of different gears as well as their wider environmental impacts.

The research has highlighted that optimisation modelling in the context of a Nephrops fishery is possible with the available data. However, there are a number of significant challenges in relation to undertaking and using such modelling that should be borne in mind. The quantity and quality of data have improved substantially in recent years, especially through the provision of Fish1 form data for under 10 metre vessels. This has allowed spatially disaggregated work to be done, however there are still gaps in the evidence base such as spatial information for 10-12 metre vessels and much of the socio-economic data are based on whole fleet segment averages and may not accurately reflect regional variations. 

This research sets out to show whether optimisation modelling could be undertaken in this area, which it has shown is possible albeit there are still points, such as those above, to take into consideration. Marine Scotland will carefully consider these points and continue to develop the evidence base, exploring new data, testing new assumptions, filling the identified evidence gaps, and taking on-board feedback from stakeholders. As such Marine Scotland welcome any feedback on the model and its outputs to allow us to create as robust an evidence base as possible for future policy and fisheries management consideration. 



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