Effects of ecosystem protection on scallop populations within a community-led temperate marine reserve

This study investigated the effects of a newly established, fully protected marine reserve on benthic habitats and two commercially valuable species of scallop in Lamlash Bay, Isle of Arran, United Kingdom. Annual dive surveys from 2010 to 2013 showed the abundance of juvenile scallops to be significantly greater within the marine reserve than outside. Generalised linear models revealed this trend to be significantly related to the greater presence of macroalgae and hydroids growing within the boundaries of the reserve. These results suggest that structurally complex habitats growing within the reserve have substantially increased spat settlement and/or survival. The density of adult king scallops declined threefold with increasing distance from the boundaries of the reserve, indicating possible evidence of spillover or reduced fishing effort directly outside and around the marine reserve. However, there was no difference in the mean density of adult scallops between the reserve and outside. Finally, the mean age, size, and reproductive and exploitable biomass of king scallops were all significantly greater within the reserve. In contrast to king scallops, the population dynamics of queen scallops (Aequipecten opercularis) fluctuated randomly over the survey period and showed little difference between the reserve and outside. Overall, this study is consistent with the hypothesis that marine reserves can encourage the recovery of seafloor habitats, which, in turn, can benefit populations of commercially exploited species, emphasising the importance of marine reserves in the ecosystem-based management of fisheries

Globalism, localism and blue food systems – How can cross-scale tensions be reduced? A production perspective from UK seafood stakeholders

‘Blue foods’ are derived from aquatic species that are caught or cultivated and are amongst the most globally traded commodities. Growing emphasis is being placed on blue foods in future transitions to sustainable food systems. However, recent international events such as the Covid-19 pandemic, UK-EU ‘Brexit’, and Russia-Ukraine war have caused renewed interest in ideological debates between globalism and localism and associated cross-scale tensions. Here, we aim to provide further insight into cross-scale tensions in blue food systems through a literature review and UK-based seafood stakeholder workshop. From our literature review, the evidence for cross-scale tensions was linked to the following themes: economic efficiency versus social justice; food security and food sovereignty; sustainability and traceability. A stakeholder workshop revealed a need for international market actors to support improvements in the social and environmental practices of blue food producers. Fully traceable supply chains that enable the transfer of information across jurisdictions were also deemed desirable to provide greater assurance on product legality and provenance. Developing a blue foods strategy at a national level was suggested as a solution to potentially rebalance the influence of international markets, with the objective of rejuvenating re-localised blue food systems. To be successful, a blue foods strategy will require the alignment and integration of policies that impact on different industry subsector