Demo-Genetic Approach for the Conservation and Restoration of a Habitat-Forming Octocoral: The Case of Red Coral, Corallium rubrum, in the Réserve Naturelle de Scandola

15 pages, 3 figures, 2 tables, supplementary material https://www.frontiersin.org/articles/10.3389/fmars.2021.633057/full#supplementary-material.-- Data Availability Statement:The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author/s

Marine protected areas (MPAs) are one of the most efficient conservation tools to buffer marine biodiversity loss induced by human activities. Beside effective enforcement, an accurate understanding of the eco-evolutionary processes underlying the patterns of biodiversity is needed to reap the benefits of management policies. In this context, integrating population genetics with demographic data, the demo-genetic approach, is particularly relevant to shift from a “species-based pattern” toward an “eco-evolutionary-based processes” conservation. Here, targeting a key species in the Mediterranean coralligenous, the red coral, Corallium rubrum, in an emblematic Mediterranean MPA, the “Réserve Naturelle de Scandola” (France), we applied demo-genetic approaches at two contrasted spatial scales, among populations and within one population, to (i) infer the demographic connectivity among populations in the metapopulation network and (ii) shed new light on the genetic connectivity and on the demographic transitions underlying the dynamics of a near-pristine population. Integrating different spatial and temporal scales, we demonstrated (i) an apparent temporal stability in the pattern of genetic diversity and structure in the MPA in spite of a dramatic demographic decline and (ii) contrasted levels of genetic isolation but substantial demographic connectivity among populations. Focusing on the near-pristine population, we complemented the characterization of red coral demographic connectivity suggesting (iii) temporal variability and (iv) the occurrence of collective dispersal. In addition, we demonstrated (v) contrasted patterns of spatial genetic structure (SGS), depending on the considered stage-class (adults vs. juveniles), in the near-pristine population. This last result points out that the overall SGS resulted from a restricted dispersal of locally produced juveniles (SGS among adults and juveniles) combined to mortality during early life stages (decrease of SGS from juveniles to adults). Demonstrating the occurrence of two management units and the importance of two populations (CAVB and ALE) for the network of connectivity, we made recommendations for the management of the Réserve Naturelle de Scandola. Besides, we contributed to the implementation of scientifically driven restoration protocols in red coral by providing estimates for the size, density, and distances among patches of transplanted colonies

This research was supported by the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 through national funds provided by the FCT – Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the program PT2020, the Spanish MINECO (CGL2012-32194), the TOTAL Foundation PERFECT project, the MIMOSA project funded by the foundation Prince Albert II de Monaco, and the European Union’s Horizon 2020 Research and Innovation Program under grant agreement N° 689518 (MERCES). [...] J-BL was funded by an assistant researcher contract framework of the RD Unit—UID/Multi/04423/2019 – Interdisciplinary Centre of Marine and Environmental Research—financed by the European Regional Development Fund (ERDF) through COMPETE2020 – Operational Program for Competitiveness and Internationalization (POCI) and national funds through FCT/MCTES (PIDDAC). Genotyping was performed at the Genome Transcriptome Facility of Bordeaux (grants from the Conseil Régional d’Aquitaine n 20030304002FA and 20040305003FA, from the European Union FEDER n 2003227 and from Investissements d’Avenir ANR-10-EQPX-16-01). This work acknowledges the “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI)

Peer reviewed