Ecological restoration of cold-water corals on the Mediterranean continental shelf

[eng] Cold-water coral (CWC) habitats dwell on continental shelves, slopes, canyons, seamounts, and ridge systems around the world’s oceans, from 50 m to depths up to 4000 m. CWC species provide heterogeneous habitats supporting a myriad of associated fauna and form highly diverse CWC reefs and CWC gardens. Main threats, currently impacting CWC ecosystems come from anthropogenic stressors, such as fishing activities, oil and gas exploitation and the incipient mining activity. Likewise, climate change, causing changes in the water column, is also affecting these ecosystems. Life-history traits of CWC species (long lifespans, slow growth and limited recruitment) make them very vulnerable to current and potential threats. Given their limited recovery capacity, interest to preserve and restore CWC ecosystem is steadily growing. The creation of Marine Protected Areas and active ecological restoration actions are nowadays the best management tools to conserve native ecosystems and represents an opportunity to revert the anthropogenic damage that has already taken place. Through passive (natural regeneration after the cessation of stressors) and active (human interacts with biotic and/or abiotic ecosystem features) approaches, restoration activities seek to accelerate the recovery of ecosystem structure and functioning relative to a reference model. Contrarily to terrestrial and shallow-water marine ecosystems, ecological restoration in intermediate (50 – 200 m) and deep marine (> 200 m) environments has received lesser attention. To date, only few restoration actions at local scales have been carried out at those depths, mainly due to technical and economic limitations which questions its wide application. Scaling-up restoration actions and make them affordable are the main present challenges for CWC restoration. In this sense, in order to move forward towards the conservation of intermediate and deep-sea ecosystems, the general aim of the present thesis is to assess the impact of fishing activity on CWC gardens as well as to explore the feasibility of novel active ecological restoration techniques. All the work performed during this thesis has been carried out at the Cap de Creus marine area (North-Western Mediterranean Sea), specifically at the continental shelf (60 – 130 m), where gorgonians, sponges, and sea pen species form CWC gardens supporting a variety of mobile associated fauna. The target species is the yellow gorgonian Eunicella cavolini (Koch, 1887) which dominate in the area forming density patches. In the first chapter, the impact of artisanal fishing was quantified to evaluate the threat of this activity on CWC gardens and to provide essential information to mitigate such impact. The rest of chapters (2, 3 and 4) evaluated, for the first time, the viability to actively restore degraded E. cavolini populations. Specifically, in the second chapter, gorgonians obtained from bycatch (accidentally caught of non-target species) of local artisanal fishers, were transplanted to artificial structures deployed on the continental shelf (805 m). This pilot study demonstrated, for the first time, the high survival of E. cavolini transplants. Following, and going one step forward, in the third chapter, field experiments and modeling approaches were combined to develop and technically validate an innovative large-scale and cost- effective restoration method for CWC gardens. Successful results evidenced the feasibility of recovering bycatch E. cavolini and returning them to their natural habitat with this novel method so-called “badminton method”. Finally, in the fourth and last chapter, a large- scale restoration action of E. cavolini populations was carried out in collaboration with local artisanal fishers during two consecutive fishing seasons by applying the technique previously developed. A large number of gorgonians (460 colonies) were successfully reintroduced and survived at the end of the action (2 years) at 80-100 m depth. The results suggested an initial establishment of a new gorgonian population, which will potentially evolve toward a comparable natural population in terms of size and spatial structure, if natural recruitment also occurs. Moreover, an economic evaluation was performed, also confirming the cost efficiency of this method aimed at enhancing the recovery of impacted CWC gardens. The lack of knowledge of some key ecological processes of CWC ecosystems as well as the technical limitations hinder a complete evaluation of restoration efforts performed. However, this thesis represents a promising improvement for the conservation and recovery of CWCs that could be extended to other areas and regions.[cat] Els coralls d’aigua freda habiten en les plataformes continentals, talussos, canyons, muntanyes submarines i dorsals oceàniques d’arreu del món, des de 50 a 4000 metres de profunditat. Les espècies de coralls d’aigua freda creen hàbitats heterogenis que donen suport a una infinitat de fauna associada i formen esculls i boscos de coralls altament diversos. Les principals amenaces que actualment impacten aquests ecosistemes de coralls d’aigua freda son d’origen antròpic, com ara l’activitat pesquera, l’explotació de petroli i gas i l’incipient explotació minera. Així mateix, el canvi climàtic, el qual provoca canvis en la columna d’aigua, també està afectant aquests ecosistemes. Les característiques vitals dels coralls d’aigua freda (longevitat, creixement lent i reclutament limitat) els fan molt vulnerables a les amaces tan actuals com futures. Atesa la seva limitada capacitat de recuperació, l’interès per preservar i restaurar els ecosistemes de coralls d’aigua freda està en constant creixement. La creació d’àrees marines protegides i les accions restauració ecològica activa són avui en dia les millors eines de gestió per conservar ecosistemes autòctons i representen una oportunitat per revertir els danys antròpics que ja han tingut lloc. A través d’enfocaments passius (regeneració natural després del cessament del impacte) i actius (l’ésser humà interacciona amb les característiques biòtiques i/o abiòtiques de l’ecosistema), les activitats de restauració busquen accelerar la recuperació de l’estructura i funcionament dels ecosistemes en funció a un model de referència. Contràriament als ecosistemes terrestres i d’aigües someres, la restauració ecològica enfocada a ambients marins intermedis (50–200 m) i profunds (> 200 m) ha rebut menor atenció. Fins ara, a aquestes profunditats només s’han dut a terme algunes poques accions de restauració a escala local, principalment a causa de limitacions tècniques i econòmiques que qüestionen la seva àmplia aplicació. Els principals reptes actuals per la restauració de coralls d’aigua freda són incrementar l’escala espacial de les accions de restauració i fer-les econòmicament més assequibles. En aquest sentit, per avançar en la conservació dels ecosistemes de fons intermedis i profunds, l’objectiu general de la present tesi és avaluar l’impacte de l’activitat pesquera sobre els boscos de coralls d’aigua freda i explorar la viabilitat de innovadores tècniques de restauració activa. Tot el treball realitzat en aquesta tesi s’ha dut a terme a la zona marina del Cap de Creus (Nord-Oest del mar Mediterrani), contretament a la plataforma continental (60 – 130 m) on espècies de gorgònies, esponges i plomalls formen boscos de coralls d’aigua freda donant suport a una gran varietat de fauna mòbil associada. L’espècie objectiu és la gorgònia groga Eunicella cavolini (Koch, 1887) la qual domina a la zona formant denses agregacions. En el primer capítol, es va quantificar el impacte de la pesca artesanal per avaluar l’amenaça d’aquesta activitat sobre els boscos de coralls d’aigua freda i proporcionar informació essencial per mitigar aquest impacte. La resta de capítols (2, 3 i 4) van avaluar, per primera vegada, viabilitat de restaurar activament les poblacions degradades de E.cavolini. Especificament, en el segon capítol és van trasplantar les gorgònies capturades accidentalment pels pescadors artesanals de la zona, a estructures artificials fondejades a la plataforma continental (85 m). Aquest estudi pilot va demostrar per primera vegada l’alta supervivència dels transplantaments d’E.cavolini. Seguidament, i anant un pas més enllà, al tercer capítol es van combinar experiments de camp i modelització per desenvolupar i validar tècnicament una nova tècnica de restauració per als boscos de coralls d’aigua freda, a gran escala i econòmicament assequible. Els exitosos resultats van evidenciar la viabilitat de recuperar les colònies de E.cavolini capturades accidentalment i retornar-les al seu hàbitat natural amb aquesta innovadora tècnica , anomenada “el mètode bàdminton”. Finalment, al quart i últim capítol, es va dur a terme una acció de restauració de les poblacions de E.cavolini a gran escala, amb la col·laboració de pescadors artesanals de la zona i al llarg de dues temporades de pesca consecutives aplicant la tècnica desenvolupada anteriorment. Un gran nombre de gorgònies (460 colònies) van ser re-introduïdes amb èxit i van sobreviure al final de l’acció (2 anys) a 80-100 m de profunditat. Els resultats van suggerir l'establiment inicial d'una nova població gorgònies, que potencialment evolucionarà cap a una població natural comparable en termes d’estructura de talles i estructura espacial, sempre i quan es produeix també un reclutament natural. D'altra banda, es va fer una avaluació econòmica, que va confirmar la rendibilitat d'aquest mètode dirigit a millorar la recuperació dels boscos de coralls d’aigua freda impactats. El desconeixement d'alguns processos ecològics claus en els ecosistemes de coralls d’aigua freda, així com les limitacions tècniques, dificulten una avaluació completa dels esforços de restauració realitzats. Tanmateix, aquesta tesi suposa una millora prometedora per a la conservació i recuperació dels coralls d’aigua feda, que es podria estendre a altres zones i regions

Estudi de la transformació de l'espai de color RGB a l'espai de color HSV

S’apliquen les tècniques clàssiques de propagació de l’error a la transformació de l’espai de color RGB en l’espai de color HSV a un conjunt de 1098 imatges test. El conjunt d’imatges test són 183 paletes de color i sis nivells d’il·luminació diferents. Els resultats que es presenten indiquen com varien la mitjana i la variància per la transformació.Preprin

An urgent call for more ambitious ocean literacy strategies in marine protected areas: a collaboration project with small-scale fishers as a case study

19 pages, 12 figures, 2 tables, supplementary material https://www.frontiersin.org/articles/10.3389/fmars.2024.1320515/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 authorCold-Water Corals play a paramount role in marine benthic ecosystems, increasing their complexity and providing spawning and nursery habitats to many species. However, due to their sessile lifestyle and ramified shape they are commonly entangled in nets and even by-caught during the practice of bottom-contact fishing, which includes impacts from both large-scale activities such as trawling and small-scale fishing (e.g., trammel nets or pots). In this context, passive and active restoration measures are crucial to avoid their damage and disappearance, which might cause the consequent loss of complexity and biodiversity of marine benthic communities. With the aim of modifying these fishing practices in the Marine Protected Area of Cap de Creus (North-Western Mediterranean), small-scale fishers and scientists (marine biologists) started a Participatory Process in which they agreed to develop a joint marine conservation program combining two distinct projects: a restoration project of the Cold-Water Corals incidentally captured on fishing nets for their subsequent reintroduction at sea (RESCAP project) and also a project on mitigation of fishing impacts on marine benthic communities (MITICAP project). Collaborative actions were carried out including interviews and exchanges of information with the purpose of collecting all the knowledge required for conducting the actions of the projects. This study shows the results of the assessment throughout five years (2017-2022) of cooperative work and highlights how crucial it is to develop long-term and revisable ocean literacy strategies for ensuring a sustainable ocean governance. An ocean literacy test evaluated the scientific knowledge of fishers at the end of the projects and revealed that despite all the efforts applied, still more work is needed, which reinforces the importance of improving the strategies of knowledge transfer for MPA management. Under the coordination of marine social anthropologists, a Cultural Consensus Analysis was conducted with the fishers. Results revealed a protoculture that should be characterized and considered when developing management strategies in the area. Additionally, the Personal Network Analysis showed that fishers have become agents of change and transmitted the learnings of the projects to their communities, fishers from nearby guilds, local educational centers and even the press. Furthermore, a list of recommendations is provided to optimize the multisector opportunities emerging from collaborative projects with marine scientists and fishers in MPAsThis work was performed under the MITICAP (https://www.programapleamar.es/miticap-implementacion-de-medidas-innovadoras-de-cooperacion-entre-pescadores-y-cientificos-para-una) and RESCAP (https://www.programapleamar.es/rescap-conservacion-y-recuperacion-de-poblaciones-de-gorgonias-y-corales-blandos-mediante) projects, which are funded by “Fundación Biodiversidad” of the Spanish Ministry for Ecological Transition, through the PLEAMAR Funding Program, co-funded by the European Maritime and Fisheries Fund. Also, the research counted with the support of the European project RESBIOS that received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Grant Agreement N°872146. In addition, the authors affiliated to the Institut de Ciències del Mar had the institutional support of the “Severo Ochoa Centre of Excellence’’ accreditation (CEX2019-000928-S)Peer reviewe

Can an emblematic species become a pest? The case of Astrospartus mediterraneus (Risso, 1826) (Echinodermata: Ophiuroidea) in the artisanal fishing grounds of the Cap de Creus area (NW Mediterranean Sea)

4th Mediterranean Symposium on the Conservation of Coralligenous & other Calcareous Bio-Concretions, 20-21 September 2022, Genoa, Italy.-- 6 pages, 2 figuresAstrospartus mediterraneus (Risso, 1826) (Echinodermata: Ophiuroidea) is an emblematic Mediterranean species yet, it has few reports and hasn’t received much attention from the marine scientific community to date. In the framework of a project to assess how to mitigate the impact of artisanal fishing on benthic communities at the Site of Community Importance (SCI) of Cap de Creus (NW Mediterranean) (MITICAP Project), an unusually high abundance of the basket star (A. mediterraneus) was observed in 2018 as part of the by-catch of the local artisanal fishers. Indeed, the fishers involved in the project reported that this species had increased in abundance and expanded its distribution over the past years, ultimately interfering with their fishing activity. This work benefits from the Local Ecological Knowledge of the fishers, analyses field surveys and aims to elucidate the abundance, distribution, size, and structure of A. mediterraneus populations; as well as to examine the possible impact this species has on the artisanal fisheries performance. Data collection was performed through bycatch photo analysis of regular fishing events from May to August, analysis of video-transects recorded by means of Remote Operated Vehicles and conducting interviews with fishers to identify the impact. Basket stars were associated with rocky substrates with presence of gorgonians located between 50 to 80 m depth, preferentially occurring on sloping areas. Despite their high abundances (0.45±0.71 ind/m2), the aggregations witnessed in the Cap de Creus area could not be determined as an outbreak due to the lack of longtime monitoring data thus, yet it seems apparent based on the LEK of the fishers that the species has been on the rise for the past years and they unanimously consider that its proliferation causes them a handicap in terms of monetary and time lossesTheir work was performed under the MitiCap and ResCap projects, which are founded by the Fundación Biodiversidad from the Ministerio para la Transición Ecológica, through the Pleamar Program, co-funded by the European Maritime and Fisheries FundPeer reviewe

Active ecological restoration of cold-water corals: techniques, challenges, costs and future directions

Cold-water coral (CWC) habitats dwell on continental shelves, slopes, seamounts, and ridge systems around the world's oceans from 50 to 4000 m depth, providing heterogeneous habitats which support a myriad of associated fauna. These highly diverse ecosystems are threatened by human stressors such as fishing activities, gas and oil exploitation, and climate change. Since their life-history traits such as long lifespan and slow growth rates make CWCs very vulnerable to potential threats, it is a foremost challenge to explore the viability of restoration actions to enhance and speed up their recovery. In contrast to terrestrial and shallow-water marine ecosystems, ecological restoration in deep marine environments has received minimal attention. This review, by means of a systematic literature search, aims to identify CWC restoration challenges, assess the most suitable techniques to restore them, and discuss future perspectives. Outcomes from the few restoration actions performed to date on CWCs, which have lasted between 1 to 4 years, provide evidence of the feasibility of coral transplantation and artificial reef deployments. Scientific efforts should focus on testing novel and creative restoration techniques, especially to scale up to the spatial and temporal scales of impacts. There is still a general lack of knowledge about the biological, ecological and habitat characteristics of CWC species exploration of which would aid the development of effective restoration measures. To ensure the long-term viability and success of any restoration action it is essential to include holistic and long-term monitoring programs, and to ideally combine active restoration with natural spontaneous regeneration (i.e., passive restoration) strategies such as the implementation of deep-sea marine protected areas (MPAs). We conclude that a combination of passive and active restoration approaches with involvement of local society would be the best optimal option to achieve and ensure CWC restoration success

Involving fishers in scaling up the restoration of cold-water coral gardens on the Mediterranean continental shelf

12 pages, 6 figures, 2 tables, supplementary data https://doi.org/10.1016/j.biocon.2021.109301Cold-water gorgonians dwelling on the continental shelf are a common by-catch of bottom-contact fishing practices. Given the slow growth and limited recruitment of cold-water gorgonians, the impact of fishing activities may seriously compromise the conservation of the highly complex coral gardens communities. For this reason, the development of effective active and passive restoration methods is nowadays a priority in order to enhance the natural recovery of impacted cold-water coral gardens. However, the ecological restoration of mesophotic and deep-sea communities remains extremely limited, due to its technological requirements and associated costs, which bring its wide-scale and long-term application into question. This study reports the preliminary results of the first large-scale active restoration of more than 400 cold-water gorgonians on the Mediterranean continental shelf. By actively involving local fishers during two consecutive fishing seasons, by-catch gorgonians were recovered and returned to the continental shelf (at 80–90 m depth). The monitoring surveys performed by using an Autonomous Underwater Vehicle (AUV) revealed that 460 gorgonian transplants survived over an area of 0.23 ha. The reintroduced cold-water gorgonian population was compared to a reference natural population in terms of size and spatial structure. The cost of the restoration amounted to 140,000 €/ha, which is significantly lower than that of any deep-sea restoration actions performed to date. The results of this cost-effective active restoration highlight the viability of large-scale restoration of impacted cold-water coral communities, with promising results for the conservation and recovery of mesophotic and deep-sea ecosystemsThis work was supported by the European Union's Horizon 2020 research and innovation program, Grant/Award Number: No 689518 (MERCES); the Fundación Biodiversidad of the Spanish Ministry for the Ecological Transition through the Pleamar Programme (RESCAP project), co-funded by the European Maritime and Fisheries Fund; Spanish Ministry for Education, Culture and Sports, Grant/Award Number: FPU 2014_06977 (FPU 2014 grant), and the Spanish Ministry for Economy and Competitiveness, Grant/Award Number: IJCI-2015-23962 (JdC 2015 grant).CL acknowledges the financial support from ICREA [ICREA Academia programme]With the institutional support of the ‘Severo OchoaCentre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe

Vertebrate populations' trends across the Iberian Peninsula

Resumen del trabajo presentado a: 2nd Meeting of the Iberian Ecological Society (SIBECOL); XXI conference of the Iberian Association of Limnology (AIL) and 21st National Congress of Ecology of the Portuguese Ecological Society (SPECO), celebrados en Aveiro (Portugal) del 3 al 8 de julio de 2022.Understanding and identifying the impacts of multiple stressors on natural populations has become a key objective for post-2020 biodiversity conservation. Of particular concern are the impacts of stressors at the local scale, which are not necessarily reflected in current global conservation assessments. As a hotspot of biodiversity, the Iberian Peninsula is an area of special interest for conservation, but it is currently facing myriad environmental problems. Yet, a synthesis of the impacts of multiple stressors on the Iberian faunal populations is glaringly missing. To contribute to this challenge, we join our efforts in an Early Career Researchers project funded by SIBECOL, which aims to synthesise current knowledge on population trends of Iberian marine, terrestrial and freshwater vertebrates, and, eventually, to identify the most common stressors for Iberian fauna populations, and their differences between major taxonomic groups and ecosystems. Here, we will present the results of the first phase of this project, whose objective was to describe the trends of Iberian vertebrate populations and identify knowledge gaps related to taxonomic groups and ecosystems. To that aim, we conducted an extensive literature review, with more than 5,000 scientific manuscripts and grey literature screened. From this initial review, and after applying data quality controls, we obtained > 1,000 population time series of Iberian vertebrates across marine, terrestrial, and freshwater ecosystems. Once we compiled this database, we analysed the population trends using a two-step modelling process: (i) first, we applied state-space models to derive the population trend of each population time series; and (ii) second, we used multilevel Bayesian models to determine the factors influencing these population trends. Overall, we found that Iberian vertebrate populations display a disparity in trends, with both declines and increases, with fishes (both marine and freshwater) being the taxa showing clear signs of decline. Additionally, we identified important gaps in monitoring data across the Iberian Peninsula, with amphibians and reptiles severely underrepresented in our dataset, despite being among the most threatened taxonomic groups. These gaps may limit our understanding of the impacts of stressors at local scales and eventually bias current conservation assessments. Overall, our approach will bridge the significant gap in our knowledge between the global and local scale conservation status of wild Iberian populations and help focus future conservation policies.Peer reviewe

Restauració ecològica de coralls d'aigua freda a la plataforma continental del Mediterrani

Memoria de tesis doctoral presentada por Maria Montseny Cuscó para obtener el título de Doctora en Ecología, Ciencias Ambientales y Fisiología Vegetal por la Universitat de Barcelona (UB), realizada bajo la dirección del Dr. Andrea Gori de la Universitat de Barcelona (UB) y del Dr. Josep-Maria Gili del Institut de Ciències del Mar (ICM-CSIC).-- 195 pages[EN] Cold-water coral (CWC) habitats dwell on continental shelves, slopes, canyons, seamounts, and ridge systems around the world's oceans, from 50 m to depths up to 4000 m. CWC species provide heterogeneous habitats supporting a myriad of associated fauna and form highly diverse CWC reefs and CWC gardens. Main threats, currently impacting CWC ecosystems come from anthropogenic stressors, such as fishing activities, oil and gas exploitation and the incipient mining activity. Likewise, climate change, causing changes in the water column, is also affecting these ecosystems. Life-history traits of CWC species (long lifespans, slow growth and limited recruitment) make them very vulnerable to current and potential threats. Given their limited recovery capacity, interest to preserve and restore CWC ecosystem is steadily growing. The creation of Marine Protected Areas and active ecological restoration actions are nowadays the best management tools to conserve native ecosystems and represents an opportunity to revert the anthropogenic damage that has already taken place. Through passive (natural regeneration after the cessation of stressors) and active (human interacts with biotic and/or abiotic ecosystem features) approaches, restoration activities seek to accelerate the recovery of ecosystem structure and functioning relative to a reference model. Contrarily to terrestrial and shallow-water marine ecosystems, ecological restoration in intermediate (50 - 200 m) and deep marine (> 200 m) environments has received lesser attention. To date, only few restoration actions at local scales have been carried out at those depths, mainly due to technical and economic limitations which questions its wide application. Scaling-up restoration actions and make them affordable are the main present challenges for CWC restoration. In this sense, in order to move forward towards the conservation of intermediate and deep-sea ecosystems, the general aim of the present thesis is to assess the impact of fishing activity on CWC gardens as well as to explore the feasibility of novel active ecological restoration techniques. All the work performed during this thesis has been carried out at the Cap de Creus marine area (North-Western Mediterranean Sea), specifically at the continental shelf (60 - 130 m), where gorgonians, sponges, and sea pen species form CWC gardens supporting a variety of mobile associated fauna. The target species is the yellow gorgonian Eunicella cavolini (Koch, 1887) which dominate in the area forming density patches. In the first chapter, the impact of artisanal fishing was quantified to evaluate the threat of this activity on CWC gardens and to provide essential information to mitigate such impact. The rest of chapters (2, 3 and 4) evaluated, for the first time, the viability to actively restore degraded E. cavolini populations. Specifically, in the second chapter, gorgonians obtained from bycatch (accidentally caught of non-target species) of local artisanal fishers, were transplanted to artificial structures deployed on the continental shelf (805 m). This pilot study demonstrated, for the first time, the high survival of E. cavolini transplants. Following, and going one step forward, in the third chapter, field experiments and modeling approaches were combined to develop and technically validate an innovative large-scale and cost-effective restoration method for CWC gardens. Successful results evidenced the feasibility of recovering bycatch E. cavolini and returning them to their natural habitat with this novel method so-called "badminton method". Finally, in the fourth and last chapter, a large-scale restoration action of E. cavolini populations was carried out in collaboration with local artisanal fishers during two consecutive fishing seasons by applying the technique previously developed. A large number of gorgonians (460 colonies) were successfully reintroduced and survived at the end of the action (2 years) at 80-100 m depth. The results suggested an initial establishment of a new gorgonian population, which will potentially evolve toward a comparable natural population in terms of size and spatial structure, if natural recruitment also occurs. Moreover, an economic evaluation was performed, also confirming the cost efficiency of this method aimed at enhancing the recovery of impacted CWC gardens. The lack of knowledge of some key ecological processes of CWC ecosystems as well as the technical limitations hinder a complete evaluation of restoration efforts performed. However, this thesis represents a promising improvement for the conservation and recovery of CWCs that could be extended to other areas and regions[CAT] Els coralls d’aigua freda habiten en les plataformes continentals, talussos, canyons, muntanyes submarines i dorsals oceàniques d’arreu del món, des de 50 a 4000 metres de profunditat. Les espècies de coralls d’aigua freda creen hàbitats heterogenis que donen suport a una infinitat de fauna associada i formen esculls i boscos de coralls altament diversos. Les principals amenaces que actualment impacten aquests ecosistemes de coralls d’aigua freda son d’origen antròpic, com ara l’activitat pesquera, l’explotació de petroli i gas i l’incipient explotació minera. Així mateix, el canvi climàtic, el qual provoca canvis en la columna d’aigua, també està afectant aquests ecosistemes. Les característiques vitals dels coralls d’aigua freda (longevitat, creixement lent i reclutament limitat) els fan molt vulnerables a les amaces tan actuals com futures. Atesa la seva limitada capacitat de recuperació, l’interès per preservar i restaurar els ecosistemes de coralls d’aigua freda està en constant creixement. La creació d’àrees marines protegides i les accions restauració ecològica activa són avui en dia les millors eines de gestió per conservar ecosistemes autòctons i representen una oportunitat per revertir els danys antròpics que ja han tingut lloc. A través d’enfocaments passius (regeneració natural després del cessament del impacte) i actius (l’ésser humà interacciona amb les característiques biòtiques i/o abiòtiques de l’ecosistema), les activitats de restauració busquen accelerar la recuperació de l’estructura i funcionament dels ecosistemes en funció a un model de referència. Contràriament als ecosistemes terrestres i d’aigües someres, la restauració ecològica enfocada a ambients marins intermedis (∼50 - 200 m) i profunds (> 200 m) ha rebut menor atenció. Fins ara, a aquestes profunditats només s’han dut a terme algunes poques accions de restauració a escala local, principalment a causa de limitacions tècniques i econòmiques que qüestionen la seva àmplia aplicació. Els principals reptes actuals per la restauració de coralls d’aigua freda són incrementar l’escala espacial de les accions de restauració i fer-les econòmicament més assequibles. En aquest sentit, per avançar en la conservació dels ecosistemes de fons intermedis i profunds, l’objectiu general de la present tesi és avaluar l’impacte de l’activitat pesquera sobre els boscos de coralls d’aigua freda i explorar la viabilitat de innovadores tècniques de restauració activa. Tot el treball realitzat en aquesta tesi s’ha dut a terme a la zona marina del Cap de Creus (Nord-Oest del mar Mediterrani), contretament a la plataforma continental (60 - 130 m) on espècies de gorgònies, esponges i plomalls formen boscos de coralls d’aigua freda donant suport a una gran varietat de fauna mòbil associada. L’espècie objectiu és la gorgònia groga Eunicella cavolini (Koch, 1887) la qual domina a la zona formant denses agregacions. En el primer capítol, es va quantificar el impacte de la pesca artesanal per avaluar l’amenaça d’aquesta activitat sobre els boscos de coralls d’aigua freda i proporcionar informació essencial per mitigar aquest impacte. La resta de capítols (2, 3 i 4) van avaluar, per primera vegada, viabilitat de restaurar activament les poblacions degradades de E.cavolini. Especificament, en el segon capítol és van trasplantar les gorgònies capturades accidentalment pels pescadors artesanals de la zona, a estructures artificials fondejades a la plataforma continental (85 m). Aquest estudi pilot va demostrar per primera vegada l’alta supervivència dels transplantaments d’E.cavolini. Seguidament, i anant un pas més enllà, al tercer capítol es van combinar experiments de camp i modelització per desenvolupar i validar tècnicament una nova tècnica de restauració per als boscos de coralls d’aigua freda, a gran escala i econòmicament assequible. Els exitosos resultats van evidenciar la viabilitat de recuperar les colònies de E.cavolini capturades accidentalment i retornar-les al seu hàbitat natural amb aquesta innovadora tècnica , anomenada “el mètode bàdminton”. Finalment, al quart i últim capítol, es va dur a terme una acció de restauració de les poblacions de E.cavolini a gran escala, amb la col·laboració de pescadors artesanals de la zona i al llarg de dues temporades de pesca consecutives aplicant la tècnica desenvolupada anteriorment. Un gran nombre de gorgònies (460 colònies) van ser re-introduïdes amb èxit i van sobreviure al final de l’acció (2 anys) a 80-100 m de profunditat. Els resultats van suggerir l'establiment inicial d'una nova població gorgònies, que potencialment evolucionarà cap a una població natural comparable en termes d’estructura de talles i estructura espacial, sempre i quan es produeix també un reclutament natural. D'altra banda, es va fer una avaluació econòmica, que va confirmar la rendibilitat d'aquest mètode dirigit a millorar la recuperació dels boscos de coralls d’aigua freda impactats. El desconeixement d'alguns processos ecològics claus en els ecosistemes de coralls d’aigua freda, així com les limitacions tècniques, dificulten una avaluació completa dels esforços de restauració realitzats. Tanmateix, aquesta tesi suposa una millora prometedora per a la conservació i recuperació dels coralls d’aigua feda, que es podria estendre a altres zones i regionsPeer reviewe