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This study evaluates the relationship between both commercial and scientific spatial fisheries data and a new satellite-based estimate of potential fish production (Ocean Productivity available to Fish, OPFish) in the European Seas. To construct OPFish, we used productivity frontal features derived from chlorophyll-a horizontal gradients, which characterize 10%–20% of the global phytoplankton production that effectively fuels higher trophic levels. OPFish is relatively consistent with the spatial distribution of both pelagic and demersal fish landings and catches per unit of effort (LPUEs and CPUEs, respectively). An index of harvest relative to ocean productivity (HP index) is calculated by dividing these LPUEs or CPUEs with OPFish. The HP index reflects the intensity of fishing by gear type with regard to local fish production. Low HP levels indicate lower LPUEs or CPUEs than expected from oceanic production, suggesting over-exploitation, while high HP levels imply more sustainable fishing. HP allows comparing the production-dependent suitability of local fishing intensities. Our results from bottom trawl data highlight that over-exploitation of demersal species from the shelves is twice as high in the Mediterranean Sea than in the North-East Atlantic. The estimate of HP index by dominant pelagic and demersal gears suggests that midwater and bottom otter trawls are associated with the lowest and highest overfishing, respectively. The contrasts of fishing intensity at local scales captured by the HP index suggest that accounting for the local potential fish production can promote fisheries sustainability in the context of ecosystem-based fisheries management as required by international marine policies., With the institutional support of the ‘Severo OchoaCentre of Excellence’ accreditation (CEX2019-000928-S).

Following a brief review of their biology, this contribution is an attempt to provide a global overview of the catches of mesopelagic fishes (of which 2.68 million tonnes were officially reported to the FAO) throughout the world ocean from 1950 to 2018, to serve as a baseline to a future development of these fisheries. The overview is based on a thorough scanning of the literature dealing with commercial or experimental fisheries for mesopelagics and their catches, and/or the mesopelagic bycatch of other fisheries. All commercial (industrial and artisanal) fisheries for mesopelagic fishes were included, as well as experimental fisheries of which we were aware, while catches performed only to obtain scientific samples were omitted. The processes of generating bycatch and causing discards are discussed, with emphasis on Russian fisheries. From peer-reviewed and gray literature, we lifted information on mesopelagic fisheries and assembled it into one document, which we then summarized into two text tables with catch data, one by country/region, the other by species or species groups.

11 pages, 7 figures, Marine Ecosystem Models (MEMs) provide a deeper understanding of marine ecosystem dynamics. The United Nations Decade of Ocean Science for Sustainable Development has highlighted the need to deploy these complex mechanistic spatial-temporal models to engage policy makers and society into dialogues towards sustainably managed oceans. From our shared perspective, MEMs remain underutilized because they still lack formal validation, calibration, and uncertainty quantifications that undermines their credibility and uptake in policy arenas. We explore why these shortcomings exist and how to enable the global modelling community to increase MEMs’ usefulness. We identify a clear gap between proposed solutions to assess model skills, uncertainty, and confidence and their actual systematic deployment. We attribute this gap to an underlying factor that the ecosystem modelling literature largely ignores: technical issues. We conclude by proposing a conceptual solution that is cost-effective, scalable and simple, because complex spatial-temporal marine ecosystem modelling is already complicated enough, MC and JS acknowledge funding from the EuroMarine 2018 call for Foresight Workshops and Working Groups proposals. JS, MC and MGP acknowledge the Spanish Ministry of Science and Innovation grant agreement N° PID2020-118097RB-I00 (ProOceans). JS, MC and YJS acknowledge the European Union's Horizon 2020 research and innovation programme under grant agreements N° 869300 (FutureMARES) and N° 817578 (TRIATLAS). ADM acknowledges the European Union's Horizon 2020 research and innovation programme under grant agreements N° 869300 (FutureMARES). MC acknowledges the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S) to the Institute of Marine Science. GR acknowledges the German Federal Ministry of Education and Research (BMBF, Humboldt Tipping project 01LC1823D). VC acknowledges support through NSERC Discovery Grant RGPIN-2019-04901. VC and GO acknowledge funding through the NSERC Mitacs Accelerate Fellowship (IT09266), IOF Ocean Leaders Fellowship, and DFO. YJS acknowledges funding support from the Biodiversa and Belmont Forum project SOMBEE (BiodivScen ERA-Net COFUND programme, ANR contract n°ANR-18-EBI4-0003-01), and the Pew marine fellows programme

The Mediterranean Large Marine Ecosystem (Med-LME) is a heterogeneous system that, despite its oligotrophic nature, has high diversity of marine species and high rate of endemism, making it one of the world hotspots for marine biodiversity. The basin is also among the most impacted Large Marine Ecosystems in the world due to the combined multiple stressors, such as fishing pressure, habitat loss and degradation, climate change, pollution, eutrophication and the introduction of invasive species. The complexity of Med-LME in its structure/function and dynamics, combined with the socio-political framework of the region make management of its marine resources quite challenging. This contribution aims at highlighting the importance of the Med-LME, with an emphasis on the state of its food web and of its fish/fisheries using modelling tools and national/international reporting. The purpose is to demonstrate the importance of an holistic framework, based on stock assessments and ecosystem based modelling approaches, to be adopted in support of management and conservation measures for the preservation and sustainable use of the Med-LME resources.

14 pages, 12 figures, 1 table, supplementary material https://doi.org/10.1016/j.marpol.2020.104296, Among FAO's Major Fishing Areas, the Mediterranean and the Black Sea had the highest percentage (62.5%) of stocks fished at unsustainable levels, especially demersal stocks. Spatial-temporal restrictions of fishing activities are important measures used for the management of marine stocks. However, sometimes these regulations are not fully implemented due to a lack of effectiveness and compliance, which contributes to their failure. Here, we developed a food-web model approach using the Ecopath with Ecosim (EwE) model representing the Fisheries Restricted Area (FRA) of the Gulf of Lion ecosystem (CoSEGoL model) prior to the establishment of the fisheries restrictions (2006–2008). We characterized the structure and functioning of the ecosystem before and after its establishment. The constructed food-web model was then fitted to the available time series of data from 2008 to 2016 to verify whether this FRA has contributed to the recovery of target demersal species and the demersal community. The fitted model was used to explore alternative future management scenarios to explore feasible management options in order to ensure a full ecosystem recovery under climate change conditions. Our results suggest a failure in the recovery of target species in the restricted area under the current management scenario, potentially revealing a lack of protection efficiency and/or enforcement. Scenarios of management options under plausible climate futures revealed possible recovery of targeted species, especially European hake. The study highlighted the importance of considering trophic interactions between predators and prey to identify trade-offs and synergies in fisheries management outcomes and the need to consider both fishing and climate dynamics, This work was funded by the EU Research Project SAFENET (“Sustainable Fisheries in EU Mediterranean waters through Network of MPAs). Call for proposal MARE/2014/41, Grant Agreement n. 721708. With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

28 pages, 7 figures, 2 tables, electronic supplementary material, Invasive alien species (IAS) have become an important driver of biodiversity change and exert severe pressure on natural ecosystems. The development of modelling approaches to assess and predict their distributions and impacts, and evaluate management options has increased substantially. We reviewed these modelling approaches, applied in aquatic ecosystems, using a systematic review approach in line with the preferred reporting items for systematic reviews and meta-analyses. According to our results, multispecies/ecosystem models dominated the applications, with dynamic and non-spatial models being the most prevalent. Most of the models included an additional stressor, mainly fisheries, climate change or nutrient loading. The impacts on biota focused on predation, but also on competition and ecosystem functioning, while the impacts on ecosystem services focused on food provision and water purification. At species/population level, most of the studies reported negative impacts; while at multispecies/ecosystem level, negative and both negative and positive impacts were similarly represented. We reflect on the ability of current models to assess different impacts of IAS populations and highlight the need to advance their capabilities to predict future impacts. Further development of models that allow capturing the arrival, establishment and spread of IAS and assess their impacts in an integrated way is still needed. Spatial–temporal modelling techniques bridging with novel analytical capabilities (such as environmental DNA to investigate the presence of IAS and metabarcoding and machine learning to predict future trophic behavior and distributions) may be the key for future achievement, XC and EO were supported by an IOLR scholarship under the DESSIM project (“A Decision Support System for the management of Israel’s Mediterranean Exclusive Economic Zone”). MC was partially funded by the European Commission through the European Union´s Horizon research program Grant Agreement No. 689518 for the MERCES project. This study was partially funded by COST (European Cooperation in Science and Technology) Action 15121 “Advancing marine conservation in the European and contiguous seas” (MarCons—http://www.marcons-cost.eu/; Katsanevakis et al. (2017))—supported by the Horizon 2020 Framework Programme for research and innovation, With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

12 pages, 8 figures, 3 tables, 1 appendix supplementary data https://doi.org/10.1016/j.ocecoaman.2020.105232, The current alarming state of many coastal ecosystems and fisheries calls for the development of tools to support recovery of exploited stocks, ensure their sustainable exploitation and protect marine ecosystems. Multi-zone Marine Protected Areas (MPAs) are often advocated to reconcile conservation and fisheries benefits. However, while there is a consensus about the ecological benefits whether such types of MPAs can really provide both benefits is still uncertain. Here, we analysed three existing Northwestern Mediterranean multi-zone MPAs (Cerbère-Banyuls, Cap de Creus and Medes Islands) using a comparative temporal ecosystem modelling approach to assess their effectiveness over time in recovering marine resources and ecosystem in the area. Our results showed differences in the ecological effectiveness of the three MPAs, potentially driven by MPA design, management and implementation features. Temporal increases of benefits were small, whenever detected, and showed slight recoveries of some target species and ecological indicators, mostly in Cerbère-Banyuls and Medes Islands MPAs. Our results confirm the benefits of protection to coastal marine resources and ecosystems when MPAs are enforced but highlight the current limitations of the three MPAs due to their small size and the significant impacts of small-scale and recreational fisheries. This study illustrates the capability to evaluate protection effects of small multi-zone MPAs with an ecosystem modelling perspective and represents the baseline to develop future scenarios of alternative management options to foster ecosystem recovery and resource rebuilding in the studied MPAs, This work was funded by EU Research Project SAFENET (“Sustainable Fisheries in EU Mediterranean waters through Network of MPAs). Call for proposal MARE/2014/41, Grant Agreement n. 721708, With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

10 pages, 6 figures, 1 table, supplementary data https://doi.org/10.1016/j.scitotenv.2020.138118, Ecosystem-based management requires an assessment of the cumulative effects of human pressures and environmental change. The operationalization and integration of cumulative effects assessments (CEA) into decision-making processes often lacks a comprehensive and transparent framework. A risk-based CEA framework that divides a CEA in risk identification, risk analysis and risk evaluation, could structure such complex analyses and facilitate the establishment of direct science-policy links. Here, we examine carefully the operationalization of such a risk-based CEA framework with the help of eleven contrasting case studies located in Europe, French Polynesia, and Canada. We show that the CEA framework used at local, sub-regional, and regional scales allowed for a consistent, coherent, and transparent comparison of complex assessments. From our analysis, we pinpoint four emerging issues that, if accurately addressed, can improve the take up of CEA outcomes by management: 1) framing of the CEA context and defining risk criteria; 2) describing the roles of scientists and decision-makers; 3) reducing and structuring complexity; and 4) communicating uncertainty. Moreover, with a set of customized tools we describe and analyze for each case study the nature and location of uncertainty as well as trade-offs regarding available knowledge and data used for the CEA. Ultimately, these tools aid decision-makers to recognize potential caveats and repercussions of management decisions. One key recommendation is to differentiate CEA processes and their context in relation to governance advice, marine spatial planning or regulatory advice. We conclude that future research needs to evaluate how effective management measures are in reducing the risk of cumulative effects. Changing governance structures takes time and is often difficult, but we postulate that well-framed and structured CEA can function as a strategic tool to integrate ecosystem considerations across multiple sectorial policies., This article is a product of the working group on cumulative effects assessment under the framework of COST Action 15121 “Advancing marine conservation in the European and contiguous seas” (MarCons; http://www.marcons-cost.eu; (Katsanevakis et al., 2017)—supported by COST (European Cooperation in Science and Technology, CA15121), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

20 pages, 9 figures, 4 tables, supplemental material https://doi.org/10.3354/meps12271, An important challenge for conserving and managing marine ecosystems is to advance our understanding of how multiple human stressors, environmental factors and marine resources interact and influence each other. The ecosystems of the Israeli Mediterranean coast have undergone significant ecological changes in recent decades, caused primarily by the introduction of alien species, fishing and the warming of the waters. Here we used a food-web model representing the continental shelf of the Israeli Mediterranean coast to explore the historical dynamics of the area considering the combined effect of alien species, fishing activities and changes in sea surface temperature and primary productivity. The food-web model was fitted to available time series of data from the early 1990s to 2010 using the temporal dynamic module of the Ecopath with Ecosim modeling approach. An important challenge was to model the numerous alien species inhabiting the Eastern Mediterranean Sea, one of the most invaded marine ecosystems of the world. Historical model simulations satisfactorily matched observed data, especially regarding alien groups. However, lack of data from the pelagic environment limited our ability to compare model output with historical observations. Trophic interactions, climate change and fishing were important factors explaining the historical dynamics of the ecosystem, which showed a degradation pattern over time. Results also highlighted an increasing proportion of alien species in biomass and catch over time, with important effects on the food web. This study represents an important step forward in understanding the changes that are occurring in the Israeli continental shelf ecosystem and the Levantine Sea, X.C. was supported by an IOLR scholarship under the DESSIM project (‘A Decision Support System for the management of Israel’s Mediterranean Exclusive Economic Zone’). M.C. was partially funded by the European Commission through the Marie Curie Career Integration Grant Fellowship No. PCIG10-GA-2011-303534 to the BIOWEB project. M.C. and J.S. were partially funded by the European Union’s Horizon research program grant agreement No. 689518 for the MERCES project

The Mediterranean Sea is one of the largest seas in the world and has a great diversity of marine species. Currently, the Mediterranean Sea is facing various threats, with alien species being one of the most important. To address this problem, it is very important to understand how alien species arrive and where they are in the Mediterranean Sea. Furthermore, it is necessary to evaluate whether alien species affect native marine species, and if so, what kind of effects they have. This article will describe our current knowledge about the effects of alien species in the Mediterranean Sea

Editorial special issue Ecopath 30 years – Modelling ecosystem dynamics: beyond boundaries with EwE.-- 4 pages, Marine and coastal ecosystems provide multiple benefits that are fundamental to human wellbeing, but human actions are disrupting and impacting the Earth's ecosystems at an alarming rate. The Ecopath approach was designed to understand the impact of the wide range of anthropogenic pressures that are exerted on the oceans, and of management options for countering these, and it has over the last thirty years grown into a complex and capable modelling framework: “Ecopath with Ecosim” – with Ecospace added on. Exciting new developments of the approach are contributing to address critical and complex issues related to the health of marine ecosystems such as invasion of species, illegal fishing activities, climate change and the development of new activities (e.g., aquaculture and infrastructure development) in coastal areas. This Special Issue presents new findings from selected case studies around the world using advanced features of Ecopath with Ecosim that were presented at the International Conference “Ecopath 30 Years-Modelling ecosystem dynamics: beyond boundaries with EwE” (November 2014, Barcelona, Spain). These contributions showcase new capabilities and findings of Ecopath with Ecosim models applications. Together these papers show that a range of diverse ecological, economic, social and governance drivers are often interacting at dynamic and temporal scales to modify marine resources, which underlines that managing marine ecosystems needs a continuous effort to integrate multiple processes, SV thanks for financial support from the Galician Government (Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia) (Grant N° R2014/023). FAS thanks CONACYT (Grant N° 221705) and COFAA and EDI programs of the Instituto Politécnico Nacional. JJH was supported by the Natural Environment Research Council and Department for Environment, Food and Rural Affairs under the project MERP (Grant N° NE/L003279/1), Marine Ecosystems Research Programme. SL acknowledges support of the Italian RITMARE Flagship Project funded by the Italian Ministry of University and Research within the National Research Program 2012–2016. MC was partially funded by the European Commission through the Marie Curie Career Integration Grant Fellowships (Grant N° PCIG10-GA-2011-303534) – to the BIOWEB project

11 pages, 7 figures, 4 tables, 1 appendix supplementary data http://dx.doi.org/10.1016/j.fishres.2015.06.028, Italy has the highest catches of all countries fishing in the Mediterranean Sea. Despite the availability of fisheries statistics at the national level, reported catch amounts account only for a portion of total fisheries removals. This study aims to provide an estimate of 1) catches for all marine fishing sectors; 2) fishing effort in the major Italian fishing fleets; and 3) catch per unit of effort from 1950 to 2010. Catches were estimated using a catch-reconstruction approach that looked at all types of fisheries removals: from reported and unreported landings (from both industrial and artisanal fisheries) to recreational landings and discards. The reconstructed total catch for the 1950–2010 time period was 2.6 times the amount reported by the FAO on behalf of Italy. Illegal, unreported and unregulated (IUU) landings constituted 53.9% of the reconstructed total catch, followed by reported catches (38.8%) and unreported discards (7.3%). Industrial fisheries were dominant, with 79.1% of the reconstructed total removals, followed by the artisanal catch (16.8%), with recreational (3.2%) and subsistence (0.9%) fisheries making very small contributions. Catch per unit of effort declined since the early 1950s. Our study is the first that estimated total Italian fisheries removals and fishing capacity using a holistic approach; such approach is particularly important in areas like the Mediterranean Sea, where the multi-species and multi-gear nature of fisheries make the assessment of single-species fisheries resources and their management difficult, A.U., D.Z. and D.P. thank the Sea Around Us, funded by The Pew Charitable Trusts and The Paul G. Allen Family Foundation

Piroddi, Chiara ... et. al.-- 17 pages, 4 figures, 5 tables, 1 appendix supplementary data http://dx.doi.org/10.1016/j.ecolind.2015.05.037, The European Union's Marine Strategy Framework Directive (MSFD) seeks to achieve, for all European seas, “Good Environmental Status” (GEnS), by 2020. Ecological models are currently one of the strongest approaches used to predicting and understanding the consequences of anthropogenic and climate-driven changes in the natural environment. We assess the most commonly used capabilities of the modelling community to provide information about indicators outlined in the MSFD, particularly on biodiversity, food webs, non-indigenous species and seafloor integrity descriptors. We built a catalogue of models and their derived indicators to assess which models were able to demonstrate: (1) the linkages between indicators and ecosystem structure and function and (2) the impact of pressures on ecosystem state through indicators. Our survey identified 44 ecological models being implemented in Europe, with a high prevalence of those that focus on links between hydrodynamics and biogeochemistry, followed by end-to-end, species distribution/habitat suitability, bio-optical (remote sensing) and multispecies models. Approximately 200 indicators could be derived from these models, the majority of which were biomass and physical/hydrological/chemical indicators. Biodiversity and food webs descriptors, with ∼49% and ∼43% respectively, were better addressed in the reviewed modelling approaches than the non-indigenous species (0.3%) and sea floor integrity (∼8%) descriptors. Out of 12 criteria and 21 MSFD indicators relevant to the abovementioned descriptors, currently only three indicators were not addressed by the 44 models reviewed. Modelling approaches showed also the potential to inform on the complex, integrative ecosystem dimensions while addressing ecosystem fundamental properties, such as interactions between structural components and ecosystems services provided, despite the fact that they are not part of the MSFD indicators set. The cataloguing of models and their derived indicators presented in this study, aim at helping the planning and integration of policies like the MSFD which require the assessment of all European Seas in relation to their ecosystem status and pressures associated and the establishment of environmental targets (through the use of indicators) to achieve GEnS by 2020, This manuscript has resulted from the DEVOTES (DEVelopment Of innovative Tools for understanding marine biodiversity and assessing good Environmental Status) project funded by the European Union under the 7th Framework Programme, ‘The Ocean of Tomorrow’ Theme (Grant Agreement No. 308392), http://www.devotes-project.eu

18 pages, 8 figures, 4 tables, supporting information https://dx.doi.org/10.1038/srep44491, The Mediterranean Sea has been defined “under siege” because of intense pressures from multiple human activities; yet there is still insufficient information on the cumulative impact of these stressors on the ecosystem and its resources. We evaluate how the historical (1950–2011) trends of various ecosystems groups/species have been impacted by changes in primary productivity (PP) combined with fishing pressure. We investigate the whole Mediterranean Sea using a food web modelling approach. Results indicate that both changes in PP and fishing pressure played an important role in driving species dynamics. Yet, PP was the strongest driver upon the Mediterranean Sea ecosystem. This highlights the importance of bottom-up processes in controlling the biological characteristics of the region. We observe a reduction in abundance of important fish species (~34%, including commercial and non-commercial) and top predators (~41%), and increases of the organisms at the bottom of the food web (~23%). Ecological indicators, such as community biomass, trophic levels, catch and diversity indicators, reflect such changes and show overall ecosystem degradation over time. Since climate change and fishing pressure are expected to intensify in the Mediterranean Sea, this study constitutes a baseline reference for stepping forward in assessing the future management of the basin, M.C. acknowledges support by the European Commission through the Marie Curie Career Integration Grant Fellowships – PCIG10-GA-2011-303534 - to the BIOWEB project. RD, MC and JS were partially funded by the European Union’s Horizon research and innovation programme grant agreement No 689518 for the MERCES project.VC acknowledges support through NSERC Discovery Grant RGPIN-2014-05782

Bundy, Alida ... et al.-- 28 pages, 6 figures, 8 tables, supporting information https://dx.doi.org/10.1111/faf.12184, Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem-based perspective, using objective and evidence-based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long-term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem-based management and governance, sustainable fisheries and healthy ecosystems go together, This is a contribution to the IndiSeas Working Group, which, by the time of the study, was cofunded by IOC-UNESCO (www.ioc-unesco.org), EuroMarine (http://www.euromarinenetwork.eu), the European FP7 MEECE research project, the European Network of Excellence Eur-Oceans and the FRB EMIBIOS project (contract n°212085)

The temporal dynamics of biogeochemical variables derived from a coupled 3-D model of the Mediterranean Sea are evaluated for the last 50 years (1960–2010) against independent data on fisheries catch per unit effort (CPUE) for the same time period. Concordant patterns are found in the time series of all of the biological variables (from the model and from fisheries statistics), with low values at the beginning of the series, a later increase, with maximum levels reached at the end of the 1990s, and a posterior stabilization. Spectral analysis of the annual biological time series reveals coincident low-frequency signals in all of them. The first, more energetic signal peaks around the year 2000, while the second, less energetic signal peaks near 1982. Almost identical low-frequency signals are found in the nutrient loads of the rivers and in the integrated nutrient levels in the surface marine ecosystem. Nitrate concentration shows a maximum level in 1998, with a later stabilization to present-day values, coincident with the first low-frequency signal found in the biological series. Phosphate shows maximum concentrations around 1982 and a posterior sharp decline, in concordance with the second low-frequency signal observed in the biological series. That result seems to indicate that the control of marine productivity (plankton to fish) in the Mediterranean is principally mediated through bottom-up processes that could be traced back to the characteristics of riverine discharges. The high sensitivity of CPUE time series to environmental conditions might be another indicator of the overexploitation of this marine ecosystem. Key Points Biogeochemical evolution of the Mediterranean over the past 50 years River nutrient loads drive primary and secondary productions Strong link between low trophic levels and fisheries

Object The authors' goal in this paper was to retrospectively evaluate the relevance of the presurgical workup and the postoperative outcome in children (< 15 years) who undergo surgery for temporal lobe epilepsy (TLE). Methods The authors performed a retrospective analysis of 68 patients (43 boys and 25 girls) who underwent resection for TLE between 2001 and 2010 at a single center and had a minimum postoperative follow-up of 12 months. Presurgical investigations included full clinical evaluation, interictal electroencephalography (EEG), and MRI in all cases; cognitive evaluation in patients older than 5 years; scalp video-EEG in 46 patients; and invasive EEG in 3 patients. Clinical evaluation included a careful assessment of ictal semiology (based on anamnestic reports or video-EEG review), with particular attention to early signs and/or symptoms suggestive of temporal lobe origin of the seizure. Microsurgical resections were performed within the anatomical limits of the temporal lobe, and surgical specimens were processed for histological examination. Postoperative assessment of seizure outcome (Engel classification system) and cognitive performance was conducted at regular intervals. The effect on postoperative seizure outcome (good = Engel Class I; poor = Engel Classes II–IV) of several presurgical and surgical variables was investigated by bivariate statistical analysis. Results All patients had at least 1 early sign or symptom suggesting a temporal lobe origin of their seizures. Lateralized interictal or ictal EEG abnormalities were seen in all patients, and they were localized to the temporal lobe in 45 patients. In all cases MRI demonstrated a structural abnormality. Surgery consisted of a tailored anterior temporal lobectomy in 64 patients and a neocortical lesionectomy in 4 patients. Postoperatively, 58 patients (85%) were in Engel Class I. Variables significantly associated with a poor outcome were preoperative sensory motor deficit (p = 0.019), mental retardation (p = 0.003), MRI abnormalities extending outside the temporal lobe (p = 0.0018), history of generalized seizures (p = 0.01) or status epilepticus (p = 0.008), unremarkable histology (p = 0.001), seizures immediately postoperatively (p = 0.00001), and ipsilateral epileptiform activity on postoperative EEG (p = 0.005). At postoperative neuropsychological assessment, the percentage of patients with a pathological score at the final visit invariably decreased compared with that at the preoperative evaluation in all considered cognitive domains. Conclusions Among the study population, a surgical selection based on a noninvasive evaluation was possible in most patients. The invaluable information resulting from the rigorous noninvasive electroclinical and neuroimaging evaluation can lead to excellent surgical results without the use of invasive, time-consuming, and expensive diagnostic tools. The potential reduction of invasiveness-related risks, complexity, and costs of presurgical investigations should hopefully allow for an increase in the number of children with TLE who will receive surgery, particularly in centers with limited technological resources.

In Europe and around the world, the approach to management of the marine environment has developed from the management of single issues (e.g., species and/or pressures) toward holistic Ecosystem Based Management (EBM) that includes aims to maintain biological diversity and protect ecosystem functioning. Within the European Union, this approach is implemented through the Marine Strategy Framework Directive (MSFD, 2008/56/EC). Integrated Ecosystem Assessment is required by the Directive in order to assess Good Environmental Status (GES). Ecological modeling has a key role to play within the implementation of the MSFD, as demonstrated here by case studies covering a range of spatial scales and a selection of anthropogenic threats. Modeling studies have a strong role to play in embedding data collected at limited points within a larger spatial and temporal scale, thus enabling assessments of pelagic and seabed habitat. Furthermore, integrative studies using food web and ecosystem models are able to investigate changes in food web functioning and biological diversity in response to changes in the environment and human pressures. Modeling should be used to: support the development and selection of specific indicators; set reference points to assess state and the achievement of GES; inform adaptive monitoring programs and trial management scenarios. The modus operandi proposed shows how ecological modeling could support the decision making process leading to appropriate management measures and inform new policy., This manuscript is a result of DEVOTES (DEVelopment Of innovative Tools for understanding marine biological diversity and assessing good Environmental Status) project, funded by the European Union under the 7th Framework Programme, “The Ocean of Tomorrow” Theme (grant agreement no. 308392), www.devotes-project.eu.

14 pages, 5 figures, 3 tables, supplementary information https://dx.doi.org/10.1038/srep34162, Mediterranean ecosystems support important processes and functions that bring direct benefits to human society. Yet, marine ecosystem services are usually overlooked due to the challenges in identifying and quantifying them. This paper proposes the application of several biophysical and ecosystem modelling approaches to assess spatially and temporally the sustainable use and supply of selected marine ecosystem services. Such services include food provision, water purification, coastal protection, lifecycle maintenance and recreation, focusing on the Mediterranean region. Overall, our study found a higher number of decreasing than increasing trends in the natural capacity of the ecosystems to provide marine and coastal services, while in contrast the opposite was observed to be true for the realised flow of services to humans. Such a study paves the way towards an effective support for Blue Growth and the European maritime policies, although little attention is paid to the quantification of marine ecosystem services in this context. We identify a key challenge of integrating biophysical and socio-economic models as a necessary step to further this research

12 pages, 5 figures, 7 tables, supplementary data https://doi.org/10.1016/j.marpol.2016.04.021, To date there has been no evaluation of the capabilities of the Baltic Sea ecosystem models to provide information as outlined by the Marine Strategy Framework Directive. This work aims to fill in this knowledge gap by exploring the modelling potential of nine Baltic Sea ecosystem models to support this specific European policy and, in particular, models' capabilities to inform on marine biodiversity. Several links are found between the Model-Derived Indicators and some of the relevant biodiversity-related descriptors (i.e. biological diversity and food webs), and pressures (i.e. interference with hydrological processes, nutrient and organic matter enrichment and marine acidification). However several gaps remain, in particular in the limited representation of habitats other than the pelagic that the models are able to address for descriptor sea-floor integrity and inability to assess descriptor non-indigenous species. The general outcome is that the Baltic Sea models considered do not adequately cover all the requested needs of the MSFD, but can potentially do so to a certain extent, while for some descriptors/criteria/indicators/pressures new indicators and/or modelling techniques need to be developed in order to satisfactorily address the requirement of the MSFD and assess the environmental status of the Baltic Sea, This manuscript has resulted from the DEVOTES (DEVelopment Of innovative Tools for understanding marine biodiversity and assessing good Environmental Status) project funded by the European Union under the 7th Framework Programme, The Ocean of Tomorrow Theme (grant agreement no. 308392), www.devotes-project.eu

Maes, Joachim... et al.-- 10 pages, 2 figures, 3 tables, supplementary material https://doi.org/10.1016/j.ecoser.2015.10.023, In the EU, the mapping and assessment of ecosystems and their services, abbreviated to MAES, is seen as a key action for the advancement of biodiversity objectives, and also to inform the development and implementation of related policies on water, climate, agriculture, forest, marine and regional planning. In this study, we present the development of an analytical framework which ensures that consistent approaches are used throughout the EU. It is framed by a broad set of key policy questions and structured around a conceptual framework that links human societies and their well-being with the environment. Next, this framework is tested through four thematic pilot studies, including stakeholders and experts working at different scales and governance levels, which contributed indicators to assess the state of ecosystem services. Indicators were scored according to different criteria and assorted per ecosystem type and ecosystem services using the common international classification of ecosystem services (CICES) as typology. We concluded that there is potential to develop a first EU wide ecosystem assessment on the basis of existing data if they are combined in a creative way. However, substantial data gaps remain to be filled before a fully integrated and complete ecosystem assessment can be carried out, Balint Czúcz was supported by the Bolyai Grant of the Hungarian Academy of Sciences under grant number BO/00138/12/8

Special issue Assessing marine ecosystems health, in an integrative way.-- 13 pages, 6 figures, 3 tables, supplementary materials https://doi.org/10.1016/j.csr.2015.10.007, Marine and coastal ecosystems are important for human wellbeing in multiple ways and yet they are subject to increasing anthropogenic stressors which pose serious threats to their health status. In this context, we used an ecosystem modeling approach to assess and quantify the health status of a semi-enclosed embayment of the Mediterranean Sea, the Amvrakikos Gulf (surface: 405 km; maximum depth: 60 m) (Ionian Sea). In particular, we built a food web model of the Gulf ecosystem for the 1980 and we fit it to time series from 1980 to 2013. The aim of the study was to: (1) investigate dynamics of marine resources in the last three decades considering the effect of changes in rivers run off, development of fish farming and dynamics of fisheries as the major anthropogenic drivers affecting the system; (2) assess structural and functional changes of the Gulf, using model derived indicators obtained from temporal simulations. Results indicated that the strongest drivers in the Amvrakikos food web were changes in nutrients and organic matter mostly from the loads of two local rivers. Trends in ecological indicators, which explained changes in the structure of the Gulf, highlighted a degradation of the demersal compartments of the food web and a relative stability of the pelagic ones mainly due to high eutrophication levels. By including several ecosystem drivers into the model, the present study is intended as a tool for assessing Amvrakikos ecosystem health and for developing future management policies in the Gulf

Coll, Marta ... et al.-- 16 pages, 6 figures, 6 tables, IndiSeas (>Indicators for the Seas>) is a collaborative international working group that was established in 2005 to evaluate the status of exploited marine ecosystems using a suite of indicators in a comparative framework. An initial shortlist of seven ecological indicators was selected to quantify the effects of fishing on the broader ecosystem using several criteria (i.e., ecological meaning, sensitivity to fishing, data availability, management objectives and public awareness). The suite comprised: (i) the inverse coefficient of variation of total biomass of surveyed species, (ii) mean fish length in the surveyed community, (iii) mean maximum life span of surveyed fish species, (iv) proportion of predatory fish in the surveyed community, (v) proportion of under and moderately exploited stocks, (vi) total biomass of surveyed species, and (vii) mean trophic level of the landed catch. In line with the Nagoya Strategic Plan of the Convention on Biological Diversity (2011-2020), we extended this suite to emphasize the broader biodiversity and conservation risks in exploited marine ecosystems. We selected a subset of indicators from a list of empirically based candidate biodiversity indicators initially established based on ecological significance to complement the original IndiSeas indicators. The additional selected indicators were: (viii) mean intrinsic vulnerability index of the fish landed catch, (ix) proportion of non-declining exploited species in the surveyed community, (x) catch-based marine trophic index, and (xi) mean trophic level of the surveyed community. Despite the lack of data in some ecosystems, we also selected (xii) mean trophic level of the modelled community, and (xiii) proportion of discards in the fishery as extra indicators. These additional indicators were examined, along with the initial set of IndiSeas ecological indicators, to evaluate whether adding new biodiversity indicators provided useful additional information to refine our understanding of the status evaluation of 29 exploited marine ecosystems. We used state and trend analyses, and we performed correlation, redundancy and multivariate tests. Existing developments in ecosystem-based fisheries management have largely focused on exploited species. Our study, using mostly fisheries independent survey-based indicators, highlights that biodiversity and conservation-based indicators are complementary to ecological indicators of fishing pressure. Thus, they should be used to provide additional information to evaluate the overall impact of fishing on exploited marine ecosystems. © 2015 Elsevier Ltd. All rights reserved, We thank the Euroceans IndiSeas Working Group funded by the European Network of Excellence EUR-OCEANS (FP6, Contract N° 511106), the European collaborative project MEECE – Marine Ecosystem Evolution in a Changing Environment (FP7, Contract N° 212085) and IRD (Institute of Research for Development) and IOC/UNESCO. [...] MC was partially funded by the European Commission through the Marie Curie Career Integration Grant Fellowships – PCIG10-GA-2011-303534 – to the BIOWEB project and by the Spanish National Program Ramon y Cajal. LJS was supported through the South African Research Chair Initiative, funded through the South African Department of Science and Technology (DST) and administered by the South African National Research Foundation (NRF). LJS and YS were also funded by the European collaborative project MEECE – Marine Ecosystem Evolution in a Changing Environment – (FP7, Contract N° 212085). KMK was supported by the Northeast Fisheries Science Center and the Nature Conservancy through a grant from the Gordon and Betty Moore Foundation. MJJJ was supported by an EU Marie Curie International Outgoing Fellowship – PIOF-GA-2013-628116. MFB was supported by the Portuguese Oceanic and Atmospheric Institute and the trawl survey data collected under Biological Sampling (PNAB) Program. LJG would like to thank the Joint Research Centre of the European Commission for support. HO was financed by the Estonian Ministry of Education and Research (Grant SF0180005s10). JJH was supported by the Natural Environment Research Council and Department for Environment, Food and Rural Affairs [Grant Number NE/L003279/1, Marine Ecosystems Research Programme]. GIvdM was supported by the Institute of Marine Research, Norway. KT was partially funded by the project PERSEUS (Policy-oriented marine Environmental Research in the Southern EUropean Seas; FP7 Contract N° 287600). MAT was funded by the Spanish Institute of Oceanography (IEO) through a Predoctoral FPI fellowship. KNM was supported by a National Research Council fellowship at the Northwest Fishery Science Center. YJS and MTT were partially supported by the French project EMIBIOS (FRB, Contract No. APP-SCEN-2010-II). Chatham Rise trawl survey data were provided by the Ministry for Primary Industries. CL acknowledges DEVOTES – Development of innovative tools for understanding marine biodiversity and assessing good Environmental Status – EC project (FP7 Grant Agreement 308392)

Over the last 2 decades marine open cage aquaculture in the Mediterranean Sea has grown rapidly, leading to increased productivity in the water column near fish farms. Here we investigated the effect of such increase in productivity on the common bottlenose dolphin Tursiops truncatus. We developed an ecosystem model for the inner Ionian Sea Archipelago, western Greece, to: (1) evaluate the trophic interactions between bottlenose dolphins and their surround- ing ecosystem, including cage-associated organisms; (2) investigate simultaneously 3 hypotheses that could explain bottlenose dolphin dynamics: (a) increasing fishing effort and changes in ocean productivity, (b) competition with other species, and (c) increase in number of fish farms; and (3) explore spatial trends in bottlenose dolphins distribution using the increased number of fish farms as an explanatory variable. Comparisons of model predictions with historical time-series data indicate that only the increase in number of cages and thereby in productivity near fish farms contributed to the trends observed in dolphin numbers. Spatial analysis also confirmed an increase in occurrence of these dolphins in the proximity of the farms. These outcomes suggest that high productivity in waters surrounding fish cages—within a coastal area that is markedly oligotrophic—may attract bottlenose dolphins. The present study shows that open cage aquacul- ture has benefited bottlenose dolphins by easing their way of catching prey. Further studies should be conducted in other areas of the Mediterranean Sea to investigate whether the higher occurrence of bottlenose dolphins around fish cages is a common pattern and if it is driven by the trophic status of the ecosystem or by the type of fishes that surround the cages.

Although overfishing has been recognized as responsible for the decline of major fish stocks, it has been less easy to demonstrate its indirect and detrimental effects on marine mammals, particularly dolphins. Competition with fisheries for the same food resources has been hypothesized to have led to the decline of several species of dolphins, including the endangered Mediterranean short-beaked common dolphin. Based on an ecosystem model for the Inner Ionian Sea Archipelago, a former hotspot for common dolphins in the Mediterranean Sea, we investigated the effect of increasing fishing effort on common dolphins, its prey and on marine biodiversity and we evaluated the outcomes of different fisheries closures (1 – closure of the purse seine fishery, 2 – closure of purse seine, trawl and beach seine fisheries, 3 – entire area closed to fisheries) ran between the years 2011 and 2030. Our results showed that local fisheries have negatively impacted the marine biodiversity of the ecosystem causing sharp declines of common dolphins and major fish stocks and weakening the robustness of the marine food web. The implementation of fisheries closures would gradually recover fish stocks, while common dolphins would increase more pronouncedly only if the study area was to be closed to all fisheries. As shown in this study, common dolphins have reflected ecosystem changes and degradation over time. Ensuring the survival of dolphin populations is thereby essential to enhance marine ecosystems and ensure sustainable fishing.

Aim A large body of knowledge exists on individual anthropogenic threats that have an impact on marine biodiversity in the Mediterranean Sea, although we know little about how these threats accumulate and interact to affect marine species and ecosystems. In this context, we aimed to identify the main areas where the interaction between marine biodiversity and threats is more pronounced and to assess their spatial overlap with current marine protected areas in the Mediterranean. Location Mediterranean Sea. Methods We first identified areas of high biodiversity of marine mammals, marine turtles, seabirds, fishes and commercial or well-documented invertebrates. We mapped potential areas of high threat where multiple threats are occurring simultaneously. Finally we quantified the areas of conservation concern for biodiversity by looking at the spatial overlap between high biodiversity and high cumulative threats, and we assessed the overlap with protected areas. Results Our results show that areas with high marine biodiversity in the Mediterranean Sea are mainly located along the central and north shores, with lower values in the south-eastern regions. Areas of potential high cumulative threats are widespread in both the western and eastern basins, with fewer areas located in the south-eastern region. The interaction between areas of high biodiversity and threats for invertebrates, fishes and large animals in general (including large fishes, marine mammals, marine turtles and seabirds) is concentrated in the coastal areas of Spain, Gulf of Lions, north-eastern Ligurian Sea, Adriatic Sea, Aegean Sea, south-eastern Turkey and regions surrounding the Nile Delta and north-west African coasts. Areas of concern are larger for marine mammal and seabird species. Main conclusions These areas may represent good candidates for further research, management and protection activities, since there is only a maximum 2% overlap between existing marine protected areas (which cover 5% of the Mediterranean Sea) and our predicted areas of conservation concern for biodiversity.

To better understand the effects of fisheries and ocean productivity on the northeastern Ionian Sea we constructed an Ecopath with Ecosim model with 22 functional groups. Data on biomass, production/biomass, consumption/biomass, and diet for each group were estimated or extrapolated from the literature. Fisheries landings and discards were also included. Temporal trajectories were simulated using Ecosim. The model was fitted with time-series data for the most important groups from 1964 to 2006. Simulations highlighted a decline of top predators and of most of the commercial species since the late 1970s. The model shows that the decline of fish resources was mainly caused by an intensive fishing pressure that occurred in the area until the end of the 1990s and also by changes in primary production that impacted the trajectories of the main functional groups. In particular, simulated changes through time in PP impacted the abundance trends of all the commercial species, showing a cascade-up effect through the ecosystem. The application of Ecopath with Ecosim was a useful tool for understanding the trends of the main functional groups of the northeastern Ionian Sea. The model underlined that management actions are needed to restore and protect target species including marine mammals, pelagic and demersal fishes. In particular, measures to reduce overfishing, illegal fishing activities and to respect existing legislations are in need. Moreover, the adoption of marine protected areas could be an effective management measure to guarantee prey survival and to sustain marine predators.

We present a new methodology for database-driven ecosystem model generation and apply the methodology to the world's 66 currently defined Large Marine Ecosystems. The method relies on a large number of spatial and temporal databases, including FishBase, SeaLifeBase, as well as several other databases developed notably as part of the Sea Around Us project. The models are formulated using the freely available Ecopath with Ecosim (EwE) modeling approach and software. We tune the models by fitting to available time series data, but recognize that the models represent only a first-generation of database-driven ecosystem models. We use the models to obtain a first estimate of fish biomass in the world's LMEs. The biggest hurdles at present to further model development and validation are insufficient time series trend information, and data on spatial fishing effort.

Once one of the most common cetaceans in the Mediterranean Sea, the short-beaked common dolphin has declined throughout the region since the 1960s and in 2003 this population was classified as Endangered in the International Union for Conservation of Nature (IUCN) Red List. Here, we document the species' precipitous decline in eastern Ionian Sea coastal waters across 13 yr. While 150 animals were present in the study area (1050 km 2 ) in 1996, only 15 were observed in 2007. A 12 mo assessment of fishing effort and catch, together with circumstantial evidence, suggests that the decline was caused largely by prey depletion resulting from overfishing. We analyzed the impacts of various fishing gear and estimated the degree of resource overlap between common dol- phins and local fisheries. The total biomass removed annually by 308 fishing boats in the study area averaged 3571 t, while that consumed by common dolphins was 17 t. Resource overlap between com- mon dolphins and fisheries — expressed as an average Pianka index of 0.5 — differed according to fishing gear, being higher for purse seiners (0.7) and beach seiners (0.4) and lower for bottom trawlers (0.1), trammel boats (0.2) and longliners (0.0). Only about 10 active purse seiners (4% of the total active fishing fleet) were responsible for 33% of the biomass removal, and likely had the greatest impact on prey of common dolphins. This study indicates a high risk of local disappearance of com- mon dolphins in the very near future, unless fishery management measures are implemented imme- diately. Purse seining should be the main management target.

We would like to thank the IndiSeas Working Group, endorsed by IOC-UNESCO (www.ioc-unesco.org) and the European Network of Excellence Euroceans (www.eur-oceans.eu). KMK was supported by Conservation International and the Sea Around Us project, a collaboration between The University of British Columbia and The Pew Charitable Trusts. MC was partially supported by the EC Marie Curie CIG grant to BIOWEB and the Spanish Research Program Ramon y Cajal. LJS was supported through the South African Research Chair Initiative, funded through the South African Department of Science and Technology (DST) and administered by the South African National Research Foundation (NRF). YJS and MIT were supported by the French project EMIBIOS (FRB, contract no. APP-SCEN-2010-11). US and YS were also funded by the European collaborative project MEECE - Marine Ecosystem Evolution in a Changing Environment - (FP7, Contract no. 212085). CPL was supported by Defra project MF1228 (From Physics to Fisheries) and DEVOTES (DEVelopment of innovative Tools for understanding marine biodiversity and assessing good Environmental Status) funded by EU FP7 (grant Agreement no. 308392), www.devotes-project.eu. GIvdM was partially supported by the Norwegian Nature Index programme and the Institute of Marine Research, Norway. HO was funded was funded by the Estonian Ministry of Education and Research (grant SF0180005s10). MAT was funded by a predoctoral FPI fellowship from the Spanish Institute of Oceanography (IEO). MJJJ was supported by the EC Marie Curie IOF Grant, PIOF-GA-2013-628116. We acknowledge all those who conducted surveys to collect the data used in this study.; Fisheries provide critical provisioning services, especially given increasing human population. Understanding where marine communities are declining provides an indication of ecosystems of concern and highlights potential conflicts between seafood provisioning from wild fisheries and other ecosystem services. Here we use the nonparametric statistic, Kendall's tau, to assess trends in biomass of exploited marine species across a range of ecosystems. The proportion of 'Non-Declining Exploited Species' (NDES) is compared among ecosystems and to three community-level indicators that provide a gauge of the ability of a marine ecosystem to function both in provisioning and as a regulating service: survey-based mean trophic level, proportion of predatory fish, and mean life span. In some ecosystems, NDES corresponds to states and temporal trajectories of the community indicators, indicating deteriorating conditions in both the exploited community and in the overall community. However differences illustrate the necessity of using multiple ecological indicators to reflect the state of the ecosystem. For each ecosystem, we discuss patterns in NDES with respect to the community-level indicators and present results in the context of ecosystem-specific drivers. We conclude that using NDES requires context-specific supporting information in order to provide guidance within a management framework. (C) 2015 Elsevier B.V. All rights reserved.

19 pages, 8 figures, 2 tables, supplementary material http://dx.doi.org/10.3354/meps11387, An ecosystem modelling approach was used to understand and assess the Mediterranean marine ecosystem structure and function as a whole. In particular, 2 food web models for the 1950s and 2000s were built to investigate: (1) the main structural and functional characteristics of the Mediterranean food web during these 2 time periods; (2) the key species/functional groups and interactions; (3) the role of fisheries and their impact; and (4) the ecosystem properties of the Mediterranean Sea in comparison with other European regional seas. Our results show that small pelagic fishes, mainly European pilchards and anchovies, prevailed in terms of biomasses and catches during both periods. Large pelagic fishes, sharks and medium pelagic fishes played a key role in the 1950s ecosystem, and have been replaced in more recent years by benthopelagic and benthic cephalopods. Fisheries showed large effects on most living groups of the ecosystem in both time periods. When comparing the Mediterranean results to those of other European regional seas modelling initiatives, the Mediterranean stood alone in relation to the type of flows (e.g. Mediterranean Sea, flow to detritus: 42%; other EU seas, consumption: 43-48%) driving the system and the cycling indices. This suggested higher levels of community stress induced by intensive fishing activities in the Mediterranean basin. This study constitutes the first attempt to build an historical and current food web model for the whole Mediterranean Sea. © Inter-Research 2015, M.C. was partially supported by a Marie Curie CIG grant - PCIG10-GA-2011-303534 - to the BIOWEB project and the Spanish Research Program Ramon y Cajal. V.C. acknowledges support from NSERC

International audience; Understanding how external pressures impact ecosystem structure and functioning is essential for ecosystem-based approaches to fisheries management. We quantified the relative effects of fisheries exploitation and environmental conditions on ecological indicators derived from two different data sources, fisheries catch data (catch-based) and fisheries independent survey data (survey-based) for 12 marine ecosystems using a partial least squares path modeling approach (PLS-PM). We linked these ecological indicators to the total biomass of the ecosystem. Although the effects of exploitation and environmental conditions differed across the ecosystems, some general results can be drawn from the comparative approach. Interestingly, the PLS-PM analyses showed that survey-based indicators were less tightly associated with each other than the catch-based ones. The analyses also showed that the effects of environmental conditions on the ecological indicators were predominantly significant, and tended to be negative, suggesting that in the recent period, indicators accounted for changes in environmental conditions and the changes were more likely to be adverse. Total biomass was associated with fisheries exploitation and environmental conditions; however its association with the ecological indicators was weak across the ecosystems. Knowledge of the relative influence of exploitation and environmental pressures on the dynamics within exploited ecosystems will help us to move towards ecosystem-based approaches to fisheries management. PLS-PM proved to be a useful approach to quantify the relative effects of fisheries exploitation and environmental conditions and suggest it could be used more widely in fisheries oceanography.

12 pages, 8 figures, 1 table, 1 appendix, The EcoTroph modeling approach was applied to five Mediterranean marine ecosystems to characterize their food webs and investigate their responses to several simulated fishing scenarios. First, EcoTroph was used to synthesize the outputs of five pre-existing heterogeneous Ecopath models in a common framework, and thus to compare different ecosystems through their trophic spectra of biomass, catch, and fishing mortalities. This approach contributes to our understanding of ecosystem functioning, from both ecological and fisheries perspectives. Then, we assessed the sensitivity of each ecosystem to fishery, using EcoTroph simulations. For the five ecosystems considered, we simulated the effects of increasing or decreasing fishing mortalities on both the biomass and the catch per trophic class. Our results emphasize that the Mediterranean Sea is strongly affected by the depletion of high trophic level organisms. Results also show that fisheries impacts, at the trophic level scale, differ between ecosystems according to their trophic structure and exploitation patterns. A top-down compensation effect is observed in some simulations where a fishing-induced decrease in the biomass of predators impacts their prey, leading to an increase in the biomass at lower trophic levels. The results of this comparative analysis highlight that ecosystems where top-down controls are observed are less sensitive to variations in fishing mortality in terms of total ecosystem biomass. This suggests that the magnitude of top-down control present in a system can affect its stability. © 2015 Elsevier B.V., This publication has been produced with the financial support of the DPF PhD fellowships program of the Institut de Recherche pour le Développement (IRD) for GH and TH. It was also partly funded by the projects BISTROMED (ENVI-Med - MISTRALS) and CHARMMED (Fondation TOTAL). MC was partially supported by a Marie Curie CIG grant (PCIG10 GA-2011-303534) to the BIOWEB project and the Spanish Research Program Ramón y Cajal. KT was partially supported by the FP7 project PERSEUS (FP7 Theme “Oceans of Tomorrow” OCEAN.2011-3 Grant Agreement No. 287600)