14 pages, 5 figures, 1 table, supporting information https://doi.org/10.1111/ele.13718.-- Data availability statement: The data and code related to the manuscript have been placed in the Dryad Digital Repository: https://doi.org/10.5061/dryad.69p8cz91g, Quantifying changes in functional community structure driven by disturbance is critical to anticipate potential shifts in ecosystem functioning. However, how marine heatwaves (MHWs) affect the functional structure of temperate coral‐dominated communities is poorly understood. Here, we used five long‐term (> 10 years) records of Mediterranean coralligenous assemblages in a multi‐taxa, trait‐based analysis to investigate MHW‐driven changes in functional structure. We show that, despite stability in functional richness (i.e. the range of species functional traits), MHW‐impacted assemblages experienced long‐term directional changes in functional identity (i.e. their dominant trait values). Declining traits included large sizes, long lifespans, arborescent morphologies, filter‐feeding strategies or calcified skeletons. These traits, which were mostly supported by few sensitive and irreplaceable species from a single functional group (habitat‐forming octocorals), disproportionally influence certain ecosystem functions (e.g. 3D‐habitat provision). Hence, MHWs are leading to assemblages that are deficient in key functional traits, with likely consequences for the ecosystem functioning, We acknowledge the funding of the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019‐000928‐S). This research has also been partially funded by the HEATMED project (RTI2018‐095346‐B‐I00, MCIU/AEI/FEDER, UE), Interreg Med Programme (Projects MPA‐ENGAGE; 5216 | 5MED18_3.2_M23_007 and MPA‐Adapt, 1MED15_3.2_M2_337) 85% cofunded by the European Regional Development Fund, the MIMOSA project funded by the Foundation Prince Albert II Monaco, the Perfect project funded by the TOTAL Foundation, the Medchange project funded by the Agence Nationale pour la Recherche (ANR) and the European Union's Horizon 2020 research and innovation programme under grants agreements 689518 (MERCES) and SEP‐210597628 (FutureMARES). D.G.G. is supported by an FPU grant (FPU15/05457) from the Spanish Ministry of Education. CL gratefully acknowledges the financial support by ICREA under the ICREA Academia programme. VB is supported by the Templeton Foundation (grant #60501, ‘Putting the Extended Evolutionary Synthesis to the Test’). J‐B.L is supported by the strategic Funding UIDB/04423/2020 and UIDP/04423/2020. [...] D.G.G, C.L, J‐B.L, N.B, P.L.S & J.G are part of the Marine Conservation research group (www.medrecover.org) (2017 SGR 1521) from the Generalitat de Catalunya., Peer reviewed

Este artículo contiene 18 páginas, 4 figuras., Climate change is causing an increase in the frequency and intensity of marine heatwaves
(MHWs) and mass mortality events (MMEs) of marine organisms are one of
their main ecological impacts. Here, we show that during the 2015–2019
period, the
Mediterranean Sea has experienced exceptional thermal conditions resulting in the
onset of five consecutive years of widespread MMEs across the basin. These MMEs
affected thousands of kilometers of coastline from the surface to 45 m, across a
range of marine habitats and taxa (50 taxa across 8 phyla). Significant relationships
were found between the incidence of MMEs and the heat exposure associated with
MHWs observed both at the surface and across depths. Our findings reveal that the
Mediterranean Sea is experiencing an acceleration of the ecological impacts of MHWs
which poses an unprecedented threat to its ecosystems' health and functioning. Overall, we show that increasing the resolution of empirical observation is critical to
enhancing our ability to more effectively understand and manage the consequences
of climate change., This paper was supported by Euromarine. Joaquim Garrabou acknowledges the funding by the “Severo Ochoa Centre of Excellence” (CEX2019-000928-S), the MCIU/AEI/FEDER [HEATMED; RTI2018-095346-B-I00], Interreg-Med Programme MPA-Engage (1MED15_3.2_M2_337), the European Union Horizon 2020 research and innovation programme (Futuremares SEP-210597628). Nuria Teixido acknowledges the French National Research Agency (4Oceans-MOPGA grant, ANR-17-MPGA-0001) and internal funds from the Stazione Zoologica Anton Dohrn. Gil Rilov was supported by the Israel Ministry of Environmental Protection. Hocein Bazairi, Free Spinosa, and Vasilis Gerovasileiou acknowledge the funding by the MAVA Fondation (MedKeyHabitats I Project) and the European Commission (Ecap-MED II Project; projects implemented by UNEP/MAP-RAC/SPA). Alfonso Ramos was supported the CIESM “Tropical Signals,” Stelios Katsanevakis and Maria Sini were supported by the Project “Coastal Environment Observatory and Risk Management in Island Regions AEGIS+” (MIS 5047038), implemented within the Operational Programme “Competitiveness, Entrepreneurship and Innovation” (NSRF 2014–2020), co-financed by the Hellenic Government (Ministry of Development and Investments) and the European Union (European Regional Development Fund, Cohesion Fund), Stelios Katsanevakis, Maria Sini and Vasilis Gerovasileiou acknowledge the support of the MARISCA Project, co-funded by 85% by the EEA GRANTS, 2009–2014, and 15% by the Public Investments Programme (PIP) of the Hellenic Republic. Ivan Guala and Daniele Grech thanks thank the support of the project “Pinna nobilis—ricerca per la sopravvivenza: un'iniziativa di Citizen Science per tracciare la mortalità di massa di Pinna nobilis in Sardegna” project and the L/7 grant (CUP 87G17000070002) funded by the Regione Autonoma Sardegna. Jean-Baptiste Ledoux 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). 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. Bernat Hereu and Cristina Linares acknowledge the support of the long-term monitoring programme of the catalan Natural Parks, funded by the Departament de Territori i Sostenibilitat of the Generalitat de Catalunya. Cristina Linares acknowledges the support of the ICREA Academia programme. David Díaz acknowledges the support the research grant CTM2016-77027-R of the Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad and Program of Marines Strategies of Spain funded by MITERD. Jamila Ben Soussi was partially funded by the Fondation Albert 2 Monaco (MIMOSA Project) and the Tropical Signals Program of CIESM. Giovanni Chimienti was supported by the Italian Ministry of Education, University and Research (PON 2014–2020, AIM 1807508–1, Linea 1), by the Ente Parco Nazionale del Gargano (Research agreement with CoNISMa N. 21/2018), and by the National Geographic Society (Grant EC-176R-18). Nathaniel Bensoussan acknowledges financial support from the European Commission through the programme “Caroline Herschell” in the context of the action “Developing Downstream applications and services on BIO-PHYsical characterization of the seascape for COASTal management” (BIOPHYCOAST). Monica Montefalcone and Annalissa Azzola collected some of their data on MMEs in the frame of the project “Mare Caldo” funded by Greenpeace Italy. Núria Marbà acknowledges financial support from the Spanish Ministries of Economy and Competitiveness (CTM2012-32603, CGL2015-71809-P) and Ministerio de Ciencia, Innovación y Universidades (RTI2018-095441-B-C21). Diego K. Kersting acknowledges support by the postdoctoral fellowship programme Beatriu de Pinós funded by the Secretary of Universities and Research (Government of Catalonia) and the Horizon 2020 programme of research and innovation of the European Union under the Marie Sklodowska-Curie grant agreement No 801370., Peer reviewed

14 pages, 5 figures, 2 tables, supplementary information https://doi.org/10.1038/s41598-022-25565-9.-- Data availability: The datasets used and/or analyzed during the current study available from the corresponding author on reasonable request, Understanding the factors and processes that shape intra-specific sensitivity to heat stress is fundamental to better predicting the vulnerability of benthic species to climate change. Here, we investigate the response of a habitat-forming Mediterranean octocoral, the red gorgonian Paramuricea clavata (Risso, 1826) to thermal stress at multiple biological and geographical scales. Samples from eleven P. clavata populations inhabiting four localities separated by hundreds to more than 1500 km of coast and with contrasting thermal histories were exposed to a critical temperature threshold (25 °C) in a common garden experiment in aquaria. Ten of the 11 populations lacked thermotolerance to the experimental conditions provided (25 days at 25 °C), with 100% or almost 100% colony mortality by the end of the experiment. Furthermore, we found no significant association between local average thermal regimes nor recent thermal history (i.e., local water temperatures in the 3 months prior to the experiment) and population thermotolerance. Overall, our results suggest that local adaptation and/or acclimation to warmer conditions have a limited role in the response of P. clavata to thermal stress. The study also confirms the sensitivity of this species to warm temperatures across its distributional range and questions its adaptive capacity under ocean warming conditions. However, important inter-individual variation in thermotolerance was found within populations, particularly those exposed to the most severe prior marine heatwaves. These observations suggest that P. clavata could harbor adaptive potential to future warming acting on standing genetic variation (i.e., divergent selection) and/or environmentally-induced phenotypic variation (i.e., intra- and/or intergenerational plasticity), This work was financially supported by the European Union's Horizon 2020 research and innovation programme [grants 689518—MERCES and SEP-210597628—FutureMARES], by MCIU/AEI/FEDER [RTI2018-095346-B-I00; HEATMED] and by the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). This research has also been funded by the Interreg Med Programme (grants 5216|5MED18_3.2_M23_007 and 1MED15_3.2_M2_337), 85% co-funded by the European Regional Development Fund. D.G-G. was supported by an FPU grant [FPU15/05457]. C.L acknowledges the support by ICREA Academia. G. P., D.P., M.C., E.A. S. and J-B. L. were funded by FCT—Foundation for Science and Technology, through UIDB/04326/2020, UIDP/04326/2020, LA/P/0101/2020, DivRestore/0013/2020. D.G-G, C.L, P.L-S, J-B. L and J.G. are part of the Marine Conservation research group [2017 SGR 1521]. M.C. was supported by a postdoctoral fellowship of project HABMAR (Grant No. MAR-01.04.02-FEAMP-0018) co-financed by the European Maritime and Fisheries Fund of the Operational Program MAR 2020 for Portugal, Peer reviewed

8 pages, 5 figures, 1 table., During the last two decades, several Marine Heatwaves (MHWs) have affected coralligenous assemblages in the Mediterranean Sea, causing catastrophic mass mortalities of several habitat-forming species such as gorgonians, corals, and sponges. Even though Marine Protected Areas (MPAs) are contributing to effectively protect marine ecosystems, the impacts associated to extreme climatic events within MPAs are jeopardizing their protective role. Therefore, minimizing local stressors within MPAs is crucial to minimize interactive effects with global, more difficult to manage, stressors. To address this, we assessed to what extent the regulation of diving frequentation can support more effective protection to climate change, focusing on the case study of the Medes Islands, which has recently suffered the impacts of different global stressors and is one of the most visited MPAs in the Mediterranean Sea. We combined 6 years of demographic data of the red gorgonian Paramuricea clavata with population modelling tools, to explore the long-term viability of this species to different managing schemes and mass mortality events scenarios. Overall, our results show that climate-adaptive management of the recreational diving activity under climate change can enhance the long-term viability of this key Mediterranean habitat-forming octocoral, which is otherwise predicted to go locally extinct at shallow depths (<25 m) within the next 20 years. This study provides one of the few attempts to quantify to what extent an adaptive management scheme may help delay climate change impacts in a Marine Protected Area, This work was supported by the long-term monitoring programme of the Natural Park of Montgrí, Medes Islands and Baix Ter protected areas funded by Departament de Territori i Sostenibilitat of the Generalitat de Catalunya public agreements PTOP-2017-130 and PTOP-2021-3. This work was also financially supported by MCIU/AEI/FEDER [RTI2018-095346-BI00; HEATMED and TED2021-131622B-I00, CORFUN] and the European Union's Horizon 2020 research and innovation programme [grant SEP-210597628—FutureMARES. Yanis Zentner was supported by an FPU grant [FPU20/03574]. C.L acknowledges the support by ICREA Academia. All authors are part of the Marine Conservation research group [2017 SGR 1521], With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

12 pages, 3 figures, supporting information https://doi.org/10.1111/geb.13685.-- Data Availability Statement: The data that support the findings of this study are openly available in ‘CORA. Repositori de Dadeds de Recerca’ at https://doi.org/10.34810/data213, Aim: Intraspecific genetic diversity is one of the pillars of biodiversity, supporting the resilience and evolutionary potential of populations. Yet, our knowledge regarding the patterns of genetic diversity at macroecological scales, so-called macrogenetic patterns, remains scarce, particularly in marine species. Marine habitat-forming (MHF) species are key species in some of the most diverse but also most impacted marine ecosystems, such as coral reefs and marine forests. We characterize the patterns and drivers of genetic diversity in MHF species and provide a macrogenetic baseline, which can be used for conservation planning and for future genetic monitoring programmes.
Location: Global.
Time period: Contemporary.
Major taxa studied: Bryozoans, hexacorals, hydrozoans, octocorals, seagrasses, seaweeds, sponges.
Methods: We analysed a database including genetic diversity estimates based on microsatellites in more than 9,000 georeferenced populations from 140 species, which belong to seven animal and plant taxa. Focusing on expected heterozygosity, we used generalized additive models to test the effect of latitude, taxon, and conservation status. We tested the correlation between the species richness and the genetic diversity.
Results: We reveal a significant but complex biogeographic pattern characterized by a bimodal latitudinal trend influenced by taxonomy. We also report a positive species genetic diversity correlation at the scale of the ecoregions. The difference in genetic diversity between protected and unprotected areas was not significant.
Main conclusions: The contrasting results between MHF animals and plants suggest that the latitudinal genetic diversity patterns observed in MHF species are idiosyncratic, as reported in terrestrial species. Our results support the existence of shared drivers between genetic and species diversities, which remain to be formally identified. Concerning, these macrogenetic patterns are not aligned from the existing network of marine protected areas. Providing the first macrogenetic baseline in MHF species, this study echoes the call regarding the need to consider genetic diversity in biodiversity assessments and management, This research was partially funded by the Spanish Ministry of Science and Innovation through the Smart project (CGL2012-32194), the HEATMED project (RTI2018-095346-B-I00, MCIU/AEI/FEDER, UE), the CORFUN project (TED2021-131622B-I00) and an EMODNET-Biology grant. AB and JBL were funded by the 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). This research was supported by the strategic funding UIDB/04423/2020, UIDP/04423/2020 and 2021.00855.CEECIND through national funds provided by FCT - Fundaço para a Ciência e a Tecnologia. JG acknowledges the funding of the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). CL gratefully acknowledges the financial support by ICREA under the ICREA Academia programme. LFF was supported by an FI SDUR grant (2020 FISDU 00482) from the ‘Generalitat de Catalunya’. LFF, IMS, MPE, JG, CL, and JBL are part of the Marine Conservation research group – MedRecover (2021 SGR 01073) from the ‘Generalitat de Catalunya’, Peer reviewed

16 pages, 4 figures, 2 tables, supplementary information https://doi.org/10.1007/s10592-023-01573-8.-- Data availability: Microsatellite genotypes will be available upon publication of the paper.-- © The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/., Current efforts to halt the decline of biodiversity are based primarily on protecting species richness. This narrow focus overlooks key components of biological diversity, particularly the infra-species genetic diversity, which is critical to consider with respect to genetic adaptation in changing environments. While comparative population genetics is recognized as a relevant approach to improve biodiversity management, it is still barely considered in practice. Here, a comparative population genetics study was conducted on two key habitat-forming octocoral species, Corallium rubrum and Paramuricea clavata, to contribute to management of two Marine Protected Areas (MPAs) in the northwestern Mediterranean. Contrasting patterns of genetic diversity and structure were observed in the two species, although they share many common biological features and live in similar habitats. Differential genetic drift effects induced by species-specific reproductive strategies and demographic histories most likely explain these differences. The translation of our results into management strategies supports the definition of four management units. We identified a coldspot of genetic diversity, with genetically isolated populations, and a hotspot of genetic diversity that has a central role in the system’s connectivity. Interestingly, they corresponded to the most recent and the oldest protected areas, respectively. This case study shows how moving from a “species pattern” perspective to an “eco-evolutionary processes” perspective can help assess and contribute to the effectiveness of biodiversity management plans., Open access funding provided by FCT|FCCN (b-on). JBL was funded by assistant researcher 2021.00855.CEECIND through national funds provided by FCT—Fundação para a Ciência e a Tecnologia. This research was supported by national funds through FCT within the scope of UIDB/04423/2020 and UIDP/04423/2020, by the MIMOSA project funded by the Foundation Prince Albert II Monaco. This work was supported by the European Union’s Horizon 2020 research and innovation program under grant agreement SEP-210597628 (FutureMARES). This study was also supported by the Spanish Government through the Smart project (CGL2012-32194) the HEATMED project (RTI2018-095346-B-I00, MCIU/AEI/FEDER, UE). RL was supported by the Agence Nationale de la Recherche (projects DISLAND ANR-20-CE32-00XXX, GENOSPACE ANR-16-CE02-0008 and INTROSPEC ANR-19-CE02-0011; and project PROLAG from the CeMEB LabEx;), and by recurrent funding from INRAe and CNRS. This research has been funded from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 869300 “FutureMARES”. SD is supported by the Fonds National de la Recherche Scientifique (FNRS, Belgium). JG and PL acknowledge the funding of the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). CL gratefully acknowledges the financial support by ICREA under the ICREA Academia program., Peer reviewed

11 pages, 3 figures, 2 tables, supporting Information https://doi.org/10.1002/aqc.4120.-- Data Availability Statement: The data that support the findings of this study are available from the corresponding author upon reasonable request, Marine habitat-forming (MHF) species in the Mediterranean are among the most threatened coastal species by human activities. In recent decades, different stressors (e.g., warming-induced marine heatwaves and algal blooms) have caused mass mortality events in these key species. Overall, a common method to assess their health status at the Mediterranean Sea scale is lacking.
To fill this gap, the aim of this work is to present and validate a cost-effective method, the Mortality Rapid Assessment Method, that is able to assess the health status of key MHF species, even through Citizen Science.
The Mortality Rapid Assessment Method is based on determining the impact of mortality on MHF species derived from the metric percentage of affected colonies or individuals. To validate the ability of the proposed method to assess the health status, it was compared to a more commonly used but time-consuming and expert-required metric based on the injured surface percentage of the colonies or individuals. For the validation, one of the most extensive (>47,500 colonies) demographic datasets of the octocoral Paramuricea clavata was used to conduct a comprehensive metric comparison.
The results showed a highly significant correlation between metrics from both methods (ρ = 0.86), confirming that the percentage of affected colonies provides a reliable assessment of the health status of gorgonian populations over broad spatial and temporal scales.
Bearing in mind that this metric can be applied to different MHF species, such as sponges, bryozoans and calcareous algae, and by non-scientific personnel (managers and trained volunteers), its implementation can contribute to inform and enhance the effectiveness of the conservation and management plans for key MHF species at the scale of the Mediterranean Sea, This research has been partially funded and supported by CORFUN project TED2021-131622B-I00 funded by Ministerio de Ciencia, Innovación y Universidades (MCIN/AEI/10.13039/501100011033) and European Union “NextGenerationEU”/PRTR, the HEATMED project RTI2018-095346-BI00 funded by MCIU/AEI/FEDER, the “Parc Natural del Montgrí, Illes Medes i Baix Ter” and the “Departament de Territori i Sostenibilitat, Generalitat de Catalunya” project (PTOP-2017-130 and PTOP-2021-3), Interreg MED Program project (MPA-Engage - Ref: 5216|5MED18_3.2_M23_007) and the European Union's Horizon 2020 research and innovation programme (grant SEP-210597628—FutureMARES). JG acknowledge the funding of the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). CL gratefully acknowledges the financial support by ICREA under the ICREA Academia program. LF was supported by FI SDUR grant (2020 FISDU 00482) from the “Generalitat de Catalunya., Peer reviewed

11 pages, 6 figures, supplementary data https://doi.org/10.1016/j.marenvres.2024.106676.-- Data availability: Data will be made available on request, Coastal areas conservation strategies often left deeper habitats, such as mesophotic ones, unprotected and exposed to anthropogenic activities. In this context, an approach for including the mesophotic zone inside protection plans is proposed, considering 27 Italian Marine Protected Areas (MPAs) as a model. MPAs were classified considering their bathymetries, exposure to marine heat waves (MHWs), mass mortality events (MMEs) and, using a local ecological knowledge (LEK) approach, the estimated resilience of certain sessile species after MMEs. Only 8 MPAs contained considerable mesophotic areas, with stronger MHWs mainly occurring in shallower MPAs, and MMEs mostly affecting coralligenous assemblages. Even with only a 10% response rate, the LEK approach provided useful information on the resilience of certain species, allowing us to suggest that the presence of nearby mesophotic areas can help shallower habitats facing climate change, thus making the “deep refugia” hypothesis, usually related to tropical habitats, applicable also for the Mediterranean Sea, The work was funded under the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.4 - Call for tender No. 3138 of December 16, 2021, rectified by Decree n.3175 of December 18, 2021 of Italian Ministry of University and Research funded by the European Union – NextGenerationEU; Project code CN_00000033, Concession Decree No. 1034 of June 17, 2022 adopted by the Italian Ministry of University and Research, CUP I33C22001300007, Project title “National Biodiversity Future Center - NBFC”. This project was also partially funded by the Interreg Med MPA Engage “Engaging Mediterranean key actors in Ecosystem Approach to manage Marine Protected Areas to face Climate change” (Grant/Award No.5216), the MERCES project (Marine Ecosystem Restoration in Changing European Seas, http://www.merces-project.eu/; Grant/Award No.689518) in the framework of the Horizon 2020, and the Spanish National Plan HEATMED project (Grant/Award No. RTI2018-095346-B-485 I00), With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), Peer reviewed

13 pages, 5 figures, supporting information https://doi.org/10.1111/gcb.17587.-- Data Availability Statement: The data and code that support the findings of this study are openly available from Zenodo at https://doi.org/10.5281/zenodo.13959703 and GitHub at https://github.com/sandrarcr/Pclavata_rec_MHW.git (in-situ temperature data, ecological data, linear models and genetic structure analysis) and in Zenodo at https://doi.org/10.5281/zenodo.14007188 and GitHub at https://github.com/Damyck/tMednet.git (detection and analysis of MHWs in the SST data). Microsatellite loci information is available from the Molecular Ecology Resources Database under accession numbers GU386255–GU386265 and PQ513430–PQ513439 and GeneBank at https://10.1111/j.1755-0998.2010.02871.x, Extreme climatic events (ECEs), such as marine heatwaves (MHWs), are a major threat to biodiversity. Understanding the variability in ecological responses to recurrent ECEs within species and underlying drivers arise as a key issue owing to their implications for conservation and population recovery. Yet, our knowledge on such ecological responses is limited since it has been frequently gathered following “single-event approaches” focused on one particular event. These approaches provide snapshots of ecological responses but fall short of capturing heterogeneity patterns that may occur among recurrent ECEs, questioning current predictions regarding biodiversity trends. Here, we adopt a “multiple events” perspective to characterize the effects of recurrent ECEs on the ecological responses in Paramuricea clavata, a Mediterranean temperate coral threatened by MHWs. Through a common-garden experiment repeated three consecutive years with the same individuals from three populations, we assessed the respective roles of environmental (year effect), genetic (population effect), and phenotypic (population-by-environment interactions effect) components in the ecological response to recurrent heat stress. The environmental component (year) was the main driver underlying the responses of P. clavata colonies across experiments. To build on this result, we showed that: (i) the ecological responses were not related to population (genetic isolation) and individual (multilocus heterozygosity) genetic make-up, (ii) while all the individuals were characterized by a high environmental sensitivity (genotype-by-environment interactions) likely driven by in situ summer thermal regime. We confront our experimental results to in situ monitoring of the same individuals conducted in 2022 following two MHWs (2018, 2022). This confirms that the targeted populations harbor limited adaptive and plastic capacities to on-going recurrent ECEs and that P. clavata might face unavoidable population collapses in shallow Mediterranean waters. Overall, we underscore the need to consider the recurrence of ECEs to assess threats to biodiversity and to forecast its evolution, This work was financially supported by the European Union’s Horizon 2020 research and innovation programme (grants 689518—MERCESSEP-210597628—FutureMARES), by Agencia Estatal de Investigación (RTI2018-095346-B-I00; HEATMED). This research has also been funded by the project CORFUN (TED2021-131622B-I00) from Agencia Estatal de Investigación and by the Short-Term Scientific Mission (STSM) grant provided by the COST Action CA20102-MAF World (E-COST-GRANT-CA20102-f04dde3c). S.R.-C. was supported by the scholarship Doctorados en el exterior No. 906 de 2021 of Ministerio de Ciencia, Tecnología e Innovación de Colombia. J.-B.L. was supported by the strategic funding UIDB/04423/2020, UIDP/04423/2020, and 2021.00855. CEECIND through national funds provided by FCT—Fundação para a Ciência e a Tecnologia. S.G.C. and J.G. acknowledge the grant “Severo Ochoa Centre of Excellence” accreditation (CEX2019-000928-S) funded by Agencia Estatal de Investigación (AEI) 10.13039/501100011033 Agencia Española de Investigación. The authors would like to thank the technician staff at the Institute of Marine Sciences, Barcelona, for their support with the experimental setup, as well as the members of MedRecover research group (2021 SGR 01073) from the “Generalitat de Catalunya” for supporting fieldwork campaigns and laboratory procedures, Peer reviewed

12 pages, 9 figures, 2 tables, supplementary data https://doi.org/10.1016/j.marenvres.2024.106822.-- Data availability: Data will be made available on request, Mediterranean gorgonians are being threatened by the impact of recurrent extreme climatic events, such as marine heatwaves (MHWs). The white gorgonian Eunicella singularis was suggested to be the most resistant gorgonian species in the NW Mediterranean, mainly due to the presence of symbiotic algae. However, a substantial shift in the conservation condition of the species has been observed in the recent years. The aim of this study is to evaluate the lethal and sublethal effects of recent MHWs on the populations of E. singularis. Our results show that recurrent MHWs have impacted both the demography and reproduction of the species between 2002 and 2020, driving mortalities up to 36%, an increase in the percentages of non-reproducing adult colonies (11–58%), and a significant decrease in the recruitment rates. Although E. singularis is a highly dynamic species in comparison with other temperate gorgonians, the present study suggests that the persistence of this species may be severely compromised under recurrent MHWs, at least at shallowest depths, This research has been partially supported by the HEATMED project (RTI2018-095346-BI00) funded by MICIU/AEI/10.13039/501100011033, the CORFUN project (TED2021-131622B-I00) funded by MICIU/AEI/10.13039/501100011033 and the European Union NextGenerationEU/PRTR, and the UndResCoral project (PID2022-137539OB-C21) funded by MICIU/AEI/10.13039/501100011033 and by FEDER, UE. JS was supported by an FI Joan Oró 2023 grant (2023 FI-1 00260) from the Ministry of Research and Universities of the "Generalitat de Catalunya" and a PREDOC-UB 2022 grant from the University of Barcelona. CL gratefully acknowledges the financial support by ICREA under the ICREA Academia Program. JG acknowledges the Severo Ochoa Centre of Excellence grant (CEX2019-000928-S) funded by MICIU/AEI/10.13039/501100011033. The authors are part of the Marine Conservation Research Group – MedRecover (2021 SGR01073) from the Generalitat de Catalunya. And AG, NV and FC are part of the COST ACTION Marine Animal Forests of the World (MAF-WORLD, CA20102) supported by COST (European Cooperation in Science and Technology), Peer reviewed

16 pages, 7 figures, 2 tables, supporting information https://doi.org/10.1111/jbi.15041.-- Data Availability Statement: The data that support the findings of this study are openly available in “CORA. Repositori de Dadeds de Recerca” at https://doi.org/10.34810/data1831, Aim: Determining the species distribution and factors shaping it is a major challenge for conservation planning. Ecological niche models (ENMs) facilitate the comprehension of how environmental factors may influence species occurrence, providing spatially explicit information relevant to conservation. Therefore, our aim was to estimate the potential distribution of key habitat-forming Mediterranean gorgonians, whose conservation would protect many co-occurring species.
Location: Mediterranean Sea.
Methods: We modelled the potential distribution of the Mediterranean gorgonians Eunicella singularis, Eunicella cavolini, Paramuricea clavata and Corallium rubrum, using an ensemble ENM that combines nine algorithms. An extensive dataset of presence records (> 4378) collected through scientific surveys and citizen-science was intersected with oceanographic and topographic information within the coralligenous habitat depth range (< 150 m). This approach was used to map the habitat suitability of the study area for each species, assess related uncertainty, identify the most important factors shaping their distribution, and evaluate the overlap with the current network of Marine Protected Areas., Results: The model identified higher habitat suitability for the occurrence of each gorgonian species in the NW Mediterranean, with roughness and temperature as the main drivers of their distribution. Conversely, the poorly sampled SE Mediterranean showed low habitat suitability, although there is a greater uncertainty associated with this estimate. The combined potential distribution of the four species is estimated to cover a quarter of Mediterranean shallow and mesophotic waters, but only 19% was included within protected areas.
Main Conclusions: The habitat suitability and uncertainty maps provide a valuable tool for the conservation and management of Mediterranean gorgonian species by, This research was funded by the following I+D+i projects: HEATMED project (RTI2018-095346-B-I00), funded by MICIU/AEI/ 10.13039/501100011033/and by “ERDF/EU”, CORFUN project (TED2021-131622B-I00) funded by MICIU/AEI/ 10.13039/501100011033 and by European Union NextGenerationEU/PRTR, UNDRESCORAL project (PID2022-137539OB-C21) funded by MCIN/AEI/ 10.13039/501100011033 and FEDER/UE and, OCEAN CITIZEN project (Grant agreement 101093010), funded by the European Union under Horizon Europe Research and Innovative programme. L.F.-F. was supported by FI SDUR grant (2020 FISDU 00482) from the “Generalitat de Catalunya”. C.L. gratefully acknowledges the financial support by ICREA under the ICREA Academia program. J.G. acknowledge the funding of the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). Y.Z. was supported by an FPU grant (FPU20/03574). F.L.M. acknowledges Fundação para a Ciência e a Tecnologia (FCT/MCTES) for the financial support to CESAM (UIDP/50017/2020 + UIDB/50017/2020 + LA/P/0094/2020) through national funds. D.A. acknowledge the financial support by a Catalan Government Grups de Recerca Consolidats grant (2021 SGR 01195). L.F.-F., C.L., Y.Z. and J.G. are part of the Marine Conservation research group—MedRecover (2021 SGR 01073) from the “Generalitat de Catalunya”, Peer reviewed

12 pages, 5 figures, supplementary materials https://doi.org/10.1126/sciadv.ado5249.-- Data and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Raw data and code used to generate the results have been placed in a public repository (https://doi.org/10.5061/dryad.j3tx95xrn), Whether restoration actions achieve full ecological recovery is still debated. This is particularly controversial in the marine realm, where the success of restoration is mostly evaluated in terms of the short-term survival of transplanted organisms. In view of this, we combined population and trait-based approaches to explore the long-term effectiveness of active restoration of a key Mediterranean octocoral. For this purpose, an assemblage with restored Corallium rubrum colonies was monitored over 10 years and compared with a nearby reference site. Our results revealed growth of the transplanted colonies followed by a change in the functional structure (i.e., dominance and diversity of traits) of the restored assemblage. This change was related not only to the development of the coral but also to the arrival and/or increase of species with different traits. Overall, our findings provide an example of how active restoration of long-lived octocorals can be an effective tool for recovering high-diverse coralligenous assemblages at decadal timescales, This work was supported by grant RTI2018-095346-B-I00 HEATMED funded by MCIN/AEI/10.13039/501100011033 and by” ERDF/UE;” grant TED2021-131622B-I00 CORFUN funded by MCIN/AEI/10.13039/501100011033 and by “European Union NextGenerationEU”/PRTR;” the Public agreement PTOP- 2017-130 Seguiment de la Biodiversitat marina funded by Generalitat de Catalunya; the Public agreement PTOP- 2021-3 Seguiment de la Biodiversitat marina funded by Generalitat de Catalunya public agreement; the grant SEP-210597628 Futuremares funded by UE H2020; grant MED0200736 MPA4Change funded by Interreg EuroMED Euro and by UE Grant ICREA Academia 2019 funded by Institució Catalana de Recerca i Estudis Avançats (to C.L.); grant Severo Ochoa Centre of Excellence CEX2019-000928-S funded by MCIU/AEI/10.13039/501100011033 (to J.G.); grant FPU20/03574 funded by MCIU/AEI/10.13039/501100011033 (to Y.Z.); and Grant 2021 SGR 01073 funded by Departament de Recerca i Universitats, Generalitat de Catalunya, Peer reviewed

14 pages, 4 figures, supporting information https://doi.org/10.1111/1365-2656.14147.- Data Availability Statement: Data and code are available from the Zotero Repository https://doi.org/10.5281/zenodo.11562876 (Capdevila et al., 2024). Temperature data are available at https://t-mednet.org/ upon request, The effects of climate change are now more pervasive than ever. Marine ecosystems have been particularly impacted by climate change, with marine heatwaves (MHWs) being a strong driver of mass mortality events. Even in the most optimistic greenhouse gas emission scenarios, MHWs will continue to increase in frequency, intensity and duration. For this reason, understanding the resilience of marine species to the increase of MHWs is crucial to predicting their viability under future climatic conditions.
In this study, we explored the consequences of MHWs on the resilience (the ability of a population to resist and recover after a disturbance) of a Mediterranean key octocoral species, Paramuricea clavata, to further disturbances to their population structure. To quantify P. clavata's capacity to resist and recover from future disturbances, we used demographic information collected from 1999 to 2022, from two different sites in the NW Mediterranean Sea to calculate the transient dynamics of their populations.
Our results showed that the differences in the dynamics of populations exposed and those not exposed to MHWs were driven mostly by differences in mean survivorship and growth. We also showed that after MHWs P. clavata populations had lower resistance and slower rates of recovery than those not exposed to MHWs. Populations exposed to MHWs had lower resistance elasticity to most demographic processes compared to unexposed populations. In contrast, the only demographic process showing some differences when comparing the speed of recovery elasticity values between populations exposed and unexposed to MHWs was stasis. Finally, under scenarios of increasing frequency of MHWs, the extinction of P. clavata populations will accelerate and their capacity to resist and recover after further disturbances will be hampered.
Overall, these findings confirm that future climatic conditions will make octocoral populations even more vulnerable to further disturbances. These results highlight the importance of limiting local impacts on marine ecosystems to dampen the consequences of climate change, This work was supported by the long-term monitoring program of the marine natural parks of Catalonia, funded by Departament de Territori i Sostenibilitat of the Generalitat de Catalunya public agreements PTOP2017-130 and PTOP-2021-3. This work was also financially supported by Heatmed project RTI2018-095346-BI00 funded by MICIU/AEI/10.13039/501100011033 and ‘ERDF A way of making Europe’, and Corfun project TED2021-131622B-I00 funded by MICIU/AEI/10.13039/501100011033 and ‘European Union NextGenerationEU/PRT’. P.C. was supported by the European Union-Next Generation EU Maria Zambrano Program (ZAMBRANO 21-26). C.L. acknowledges the support by ICREA Academia. All authors are part of the Marine Conservation research group [2021 SGR 01073], With funding form the Spanish government through the "Severa Ochoa Centre of Excellence" accreditation (CEX2019-000928-S), Peer reviewed

8 pages, 2 figures.- Data Availability Statement: Data are available from the Dryad Digital Repository: http://doi.org/10.5061/dryad.tmpg4f569 (Rovira et al., 2024), Climate change is impacting ecosystems worldwide, and the Mediterranean Sea is no exception. Extreme climatic events, such as marine heat waves (MHWs), are increasing in frequency, extent and intensity during the last decades, which has been associated with an increase in mass mortality events for multiple species.
Coralligenous assemblages, where the octocoral Paramuricea clavata lives, are strongly affected by MHWs. The Medes Islands Marine Reserve (NW Mediterranean) was considered a climate refugia for P. clavata, as their populations were showing some resilience to these changing conditions.
In this study, we assessed the impacts of the MHWs that occurred between 2016 and 2022 in seven shallow populations of the octocoral P. clavata from a Mediterranean Marine Protected Area.
The years that the mortality rates increased significantly were associated with the ones with strong MHWs, 2022 being the one with higher mortalities. In 2022, with 50 MHW days, the proportion of total affected colonies was almost 70%, with a proportion of the injured surface of almost 40%, reaching levels never attained in our study site since the monitoring was started.
We also found spatial variability between the monitored populations. Whereas few of them showed low levels of mortality, others lost around 75% of their biomass.
The significant impacts documented here raise concerns about the future of shallow P. clavata populations across the Mediterranean, suggesting that the resilience of this species may not be maintained to sustain these populations face the ongoing warming trends, This work was supported by the long-term monitoring programme of the marine natural parks of Catalonia, funded by Departament de Territori i Sostenibilitat of the Generalitat de Catalunya public agreements PTOP2017-130 and PTOP-2021-3. This work was also financially supported by Heatmed project RTI2018-095346-BI00 funded by Agencia Española de Investigación AEI MICIU/AEI/10.13039/501100011033 and ‘ERDF A way of making Europe’, and Corfun project TED2021-131622B-I00 funded by MICIU/AEI/10.13039/501100011033 and ‘European Union NextGenerationEU/PRT’. C.L acknowledges the support by Catalan Institution for Research and Advanced Studies ICREA. All authors are part of the Marine Conservation research group funded by Generalitat de Catalunya [2021 SGR 01073], With funding form the Spanish government through the "Severa Ochoa Centre of Excellence" accreditation (CEX2019-000928-S), Peer reviewed

15 pages, 6 figures, supplementary material https://www.frontiersin.org/articles/10.3389/fmars.2025.1631835/full#supplementary-material.-- Data availability statement: The dataset supporting the findings of this study is openly available at 'CORA. Repositori de Dades de Recerca' at https://doi.org/10.34810/data2269, Knowledge of habitat and species’ distributions and their conservation status is crucial to enhance their conservation and management plans, which is especially urgent in the current era of rapid environmental change driven by anthropogenic activities. Scientists have been collecting data for several decades on the coralligenous assemblages in the Mediterranean Sea, one of the most important habitats with high levels of associated biodiversity. However, the inconsistency, lack of harmonisation, and dispersion of data across different sources limit their applicability in sound, broad-scale strategies. Here, we present the CorMedNet database, a collaborative and open-access initiative designed to boost the acquisition of baseline information on the distribution, demography, and population genetics data of Mediterranean coralligenous assemblages. Through a literature review, the CorMedNet database compiled 8575 georeferenced records representing local populations of 418 macroinvertebrate species. Although currently limited to cnidarians, poriferans, and bryozoans, CorMedNet is designed to encompass the full diversity of coralligenous species, including other relevant taxa such as calcareous algae. This version represents the most comprehensive dataset available to date for macroinvertebrate species inhabiting coralligenous habitats. The analysis of the compiled data showed that records were mainly from a limited number (14) of species which are considered habitat-forming species. Moreover, information is geographically biased towards the NW Mediterranean and mainly related to species distribution. Demographic and population genetic studies represent only 26.7% of records. In addition, there is a lack of long-term demographic studies, hindering our ability to examine the conservation status of populations at relevant temporal scales. For that reason, the ultimate goal of the CorMednet initiative is to provide a common platform to foster continuous data integration while identifying the main gaps in knowledge. We therefore expect that CorMedNet will also become a key resource to guide research actions and support the design and implementation of effective conservation and management strategies for the unique Mediterranean coralligenous, This research was funded by the following I+D+i projects: HEATMED project (RTI2018-095346-B-I00), funded by MICIU/AEI/10.13039/501100011033 and by ERDF/EU, CORFUN project (TED2021-131622B-I00) funded by MICIU/A EI/10.13039/501100011033 and by European Union NextGenerationEU/PRTR, UNDRESCORAL project (PID2022-137539OB-C21) funded by MCIN/AEI/10.13039/501100011033 and FEDER/UE, and MPA4Change (MED0200736) funded by Interreg EuroMED program. LF-F was supported by the FI SDUR grant (2020 FISDU 00482) from the ‘Generalitat de Catalunya’. CL gratefully acknowledges the financial support from ICREA under the ICREA Academia program. JG acknowledges the Spanish government’s funding through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S). PH-G was supported by the PREDOCS-UB grant from the University of Barcelona. J-BL was supported by the strategic funding UIDB/04423/2020, UIDP/04423/2020, and 2021.00855 CEECIND through national funds provided by FCT—Fundação para a Ciência e a Tecnologia. LF-F, CL, JG, DG-G, PH-G, and J-BL are part of the Marine Conservation research group MedRecover (2021 SGR 01073) from the ‘Generalitat de Catalunya’, Peer reviewed

Marine heatwaves (MHWs) are driving mass mortalities of coastal foundation species globally, threatening their persistence and the ecosystems they support. However, long-term demographic evidence of these impacts at regional scales is scarce. Accordingly, whether ongoing conservation actions, mainly marine protected areas (MPAs), mitigate the impact of MHWs is still an open question. Here, we address these gaps by analysing over two decades of demographic monitoring data from 49 shallow (< 40 m depth) populations of the foundation gorgonian Paramuricea clavata paired with in situ temperature records across the north-western Mediterranean (38°–43° N, 0°–8° E). Using hierarchical Bayesian models, we estimated regional-scale trends and assessed the combined influence of MHW exposure and protection status. We found that increasingly frequent extreme thermal events have caused widespread mass mortality, resulting in a 45% median decline in biomass at the regional scale over the past two decades. Within this context of extensive decline, protection temporarily buffered MHW impacts by sustaining higher overall biomass, despite protected populations experiencing greater absolute losses. Taken together, these findings indicate that local protection alone cannot offset climate-driven mortality and underscore the urgent need to integrate conservation measures with global climate action to preserve shallow marine ecosystems., This work was supported by MCIN/AEI/10.13039/501100011033 and by “ERDF/UE”, RTI2018-095346-BI00 (HEATMED); MCIN/AEI/10.13039/501100011033 and by the “European Union NextGenerationEU”/PRTR, TED2021-131622B-I00 (CORFUN); MCIN/AEI/10.13039/501100011033, PID2022-137539OA-C22 (UNDRESCORAL), FPU Fellowship (FPU20/03574), Severo Ochoa Centre of Excellence Grant CEX2024-001494-S; European Union H2020, SEP-210597628 (Futuremares); Interreg EuroMED and the European Union, MED0200736 (MPA4Change)., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2024-001494-S)., Peer reviewed