Recovery and expansion of rhodoliths beds and Laminaria rodriguezii forests after bottom trawl ban

Abstract Rhodolith beds and Laminaria rodriguezii forests constitute marine habitats of high conservation value. In the Menorca Channel (Balearic Islands, Western Mediterranean) rhodolith beds predominate in the sedimentary bottoms of the continental shelf and in some areas, these bottoms present an erect stratum with L. rodriguezii. Bottom trawling has negative impacts on rhodolith beds and, specially, on L. rodriguezii forests due to the direct effects of extraction and mechanical destruction and indirect effects related to sediment resuspension and posterior settlement that promotes burial. In this work we compare the distribution of rhodolith beds and L. rodriguezii forests in the Site of Community Importance (SCI) of the Menorca Channel before and after 2016, when a Fishing Protection Zone (FPZ) banning trawling was established. Since the implementation of the FPZ the extension of both rhodolith beds and L. rodriguezii forests have shown an increase of 6% and 54% respectively, and biomass of rhodolith-forming species and L. rodriguezii showed higher values than before the FPZ. The improvement of these habitats in the SCI Menorca Channel evidences that the bottom trawl ban is an effective measure for the conservation and restoration of benthic communities and habitats. This is particularly relevant in the case of rhodolith beds and L. rodriguezii forests due to their ecological importance and their role as essential fish habitats that improve the sustainability of marine living resources.