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

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.

Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was performed within the framework of: (i) SosMed project (Improvement of the scientific and technical knowledge for the sustainability of demersal fisheries in the western Mediterranean), funded by Next Generation European funds (Recovery, Transformation and Resilience Plan), from an agreement between the Spanish Ministry of Agriculture, Fisheries and Food and the Spanish National Research Council (CSIC), by means of the Spanish Institute of Oceanography (IEO); and (ii) 18-ESMARES2-CIRCA project, included in the program “Asesoramiento científico-técnico para la protección del medio marino: Evaluación y seguimiento de las Estrategias Marinas, Seguimiento de los espacios marinos protegidos de competencia estatal (2018–2021)”, funded by the General Directorate of Sea Protection of the Spanish Ministry for the Ecological Transition and the Demographic Challenge. Some of the aforementioned research surveys were funded by the following projects: (iii) CANAL (Integral study of Menorca Channel and its fishery exploitation), funded by the Directorate of Fisheries of the Autonomous Government of the Balearic Islands and MarViva Foundation; (iv) LIFE + INDEMARES (Inventario y designación de la Red Natura 2000 en áreas marinas del Estado español), funded by the European Union’s LIFE programme; (v) EQUIPAR (Acción Especial para la adquisición de equipamiento para el estudio de los hábitats sensibles de la plataforma de las Islas Baleares), funded by the Autonomous Government of the Balearic Islands; (vi) LIFE IP INTEMARES (Gestión integrada, innovadora y participativa de la Red Natura 2000 en el medio marino español), coordinated by the Biodiversity Foundation of the Ministry for the Ecological Transition and the Demographic Challenge and receiving financial support from the European Union’s LIFE programme (LIFE15/IPE/ES/000012); (vii) MARFISH (A multidisciplinary approach to assess the responses of fishing resources to protection), funded by Autonomous Government of the Balearic Islands (PDR/2020/69); and viii) BIODIV project: “Scientific and technical advice for the monitoring of marine biodiversity: protected marine areas and species of state competence (2022–2025)”; funded by the European Union - NextGenerationEU through the Recovery, Transformation and Resilience Plan; and promoted by the Directorate General for Biodiversity, Forests and Desertification of the Ministry for Ecological Transition and the Demographic Challenge and CSIC, through the Spanish Institute of Oceanography (IEO). The MEDITS surveys are co-funded by the European Union through the European Maritime and Fisheries Fund (EMFF), within the National Program of collection, management, and use of data in the fisheries sector and support for scientific advice regarding the Common Fisheries Policy.

Peer reviewed