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Since the 1980s, the Common Fisheries Policy (CFP) has shaped European fisheries. It has often been criticised for being too prescriptive and, above all, for failing to protect either fishermen or ecosystems. The last reform dates back to the early 2010 s and has led to a slight but slow improvement in the state of ecosystems. Given that the CFP is in the process of evaluation, a group of French fishery scientists set up an initiative to add to the debate on what should be retained, reinforced or added to a possible new reform. This initiative came 10 years after a previous manifesto that presented their vision for fisheries in Europe. Four major issues emerged from the current initiative: (1) a need for transparency and simplification in fisheries management, (2) a need for more consultation and dialogue between stakeholders, (3) the urgency of the situation in the Mediterranean Sea, and (4) the necessity of putting into practice all research developments for an ecosystem approach to fisheries. Compared to 10 years ago, the response of scientists shows that the focus is no longer on achieving the maximum sustainable yield, but rather on the following steps to protect ecosystems and fisheries. An ecosystem approach to fisheries remains indispensable for both ecosystems and fishing activities. To this end, scientists put forward numerous proposals to improve the CFP, acknowledging that the final solutions should emerge from consultation with stakeholders. Climate change, an issue raised much more than in the manifest, reinforces the need to act.

Since the 1980s, the Common Fisheries Policy (CFP) has shaped European fisheries. It has often been criticised for being too prescriptive and, above all, for failing to protect either fishermen or ecosystems. The last reform dates back to the early 2010 s and has led to a slight but slow improvement in the state of ecosystems. Given that the CFP is in the process of evaluation, a group of French fishery scientists set up an initiative to add to the debate on what should be retained, reinforced or added to a possible new reform. This initiative came 10 years after a previous manifesto that presented their vision for fisheries in Europe. Four major issues emerged from the current initiative: (1) a need for transparency and simplification in fisheries management, (2) a need for more consultation and dialogue between stakeholders, (3) the urgency of the situation in the Mediterranean Sea, and (4) the necessity of putting into practice all research developments for an ecosystem approach to fisheries. Compared to 10 years ago, the response of scientists shows that the focus is no longer on achieving the maximum sustainable yield, but rather on the following steps to protect ecosystems and fisheries. An ecosystem approach to fisheries remains indispensable for both ecosystems and fishing activities. To this end, scientists put forward numerous proposals to improve the CFP, acknowledging that the final solutions should emerge from consultation with stakeholders. Climate change, an issue raised much more than in the manifest, reinforces the need to act.

We propose an innovative and generic methodology to analyse individual and collective behaviour through individual trajectory data. The work is motivated by the analysis of GPS trajectories of fishing vessels collected from regulatory tracking data in the context of marine biodiversity conservation and ecosystem-based fisheries management. We build a low-dimensional latent representation of trajectories using convolutional neural networks as non-linear mapping. This is done by training a conditional variational auto-encoder taking into account covariates. The posterior distributions of the latent representations can be linked to the characteristics of the actual trajectories. The latent distributions of the trajectories are compared with the Bhattacharyya coefficient, which is well-suited for comparing distributions. Using this coefficient, we analyse the variation of the individual behaviour of each vessel during time. For collective behaviour analysis, we build proximity graphs and use an extension of the stochastic block model for multiple networks. This model results in a clustering of the individuals based on their set of trajectories. The application to French fishing vessels enables us to obtain groups of vessels whose individual and collective behaviours exhibit spatio-temporal patterns over the period 2014-2018.

We propose a database to describe the Bay of Biscay mixed demersal European fishery over the period 2010–2020 for the ISIS-Fish simulation tool. It was built upon national and European fishing databases, scientific survey datasets, models estimates, literature, and the formulation of assumptions. It accounts explicitly for spatial and seasonal processes, and for mixed fisheries phenomenons. This database encompasses population dynamics for 3 stocks, hake, sole and Norway lobster, exploitation dynamics for numerous fleets and métiers, and the description of current fishing management, as well as fishers adaptation. A calibration procedure was designed to ensure consistency between all these diverse and heterogeneous parameters compiled and estimated in the ISIS-Fish database and to ensure the model reproduces closely historical catch patterns. This database is a starting point towards operational simulations, of use for understanding the functioning of the fishery, the assessment of management strategies, or delivering short and long-term scenarios. It can be used to reproduce historical catch patterns, with room for improvement on some inter-annual and spatial dynamics.

We propose a database to describe the Bay of Biscay mixed demersal European fishery over the period 2010–2020 for the ISIS-Fish simulation tool. It was built upon national and European fishing databases, scientific survey datasets, models estimates, literature, and the formulation of assumptions. It accounts explicitly for spatial and seasonal processes, and for mixed fisheries phenomenons. This database encompasses population dynamics for 3 stocks, hake, sole and Norway lobster, exploitation dynamics for numerous fleets and métiers, and the description of current fishing management, as well as fishers adaptation. A calibration procedure was designed to ensure consistency between all these diverse and heterogeneous parameters compiled and estimated in the ISIS-Fish database and to ensure the model reproduces closely historical catch patterns. This database is a starting point towards operational simulations, of use for understanding the functioning of the fishery, the assessment of management strategies, or delivering short and long-term scenarios. It can be used to reproduce historical catch patterns, with room for improvement on some inter-annual and spatial dynamics.

We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of single life stages or the whole life cycle of species, 3) food web models, and 4) end-to-end models. Single pressures are rare and, in the future, models must be able to examine multiple factors affecting living marine resources such as interactions between: i) climate-driven changes in temperature regimes and acidification, ii) reductions in water quality due to eutrophication, iii) the introduction of alien invasive species, and/or iv) (over-)exploitation by fisheries. Statistical (correlative) approaches can be used to detect historical patterns which may not be relevant in the future. Advancing predictive capacity of changes in distribution and productivity of living marine resources requires explicit modelling of biological and physical mechanisms. New formulations are needed which (depending on the question) will need to strive for more realism in ecophysiology and behaviour of individuals, life history strategies of species, as well as trophodynamic interactions occurring at different spatial scales. Coupling existing models (e.g. physical, biological, economic) is one avenue that has proven successful. However, fundamental advancements are needed to address key issues such as the adaptive capacity of species/groups and ecosystems. The continued development of end-to-end models (e.g., physics to fish to human sectors) will be critical if we hope to assess how multiple pressures may interact to cause changes in living marine resources including the ecological and economic costs and trade-offs of different spatial management strategies. Given the strengths and weaknesses of the various types of models reviewed here, confidence in projections of changes in the distribut

We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of single life stages or the whole life cycle of species, 3) food web models, and 4) end-to-end models. Single pressures are rare and, in the future, models must be able to examine multiple factors affecting living marine resources such as interactions between: i) climate-driven changes in temperature regimes and acidification, ii) reductions in water quality due to eutrophication, iii) the introduction of alien invasive species, and/or iv) (over-)exploitation by fisheries. Statistical (correlative) approaches can be used to detect historical patterns which may not be relevant in the future. Advancing predictive capacity of changes in distribution and productivity of living marine resources requires explicit modelling of biological and physical mechanisms. New formulations are needed which (depending on the question) will need to strive for more realism in ecophysiology and behaviour of individuals, life history strategies of species, as well as trophodynamic interactions occurring at different spatial scales. Coupling existing models (e.g. physical, biological, economic) is one avenue that has proven successful. However, fundamental advancements are needed to address key issues such as the adaptive capacity of species/groups and ecosystems. The continued development of end-to-end models (e.g., physics to fish to human sectors) will be critical if we hope to assess how multiple pressures may interact to cause changes in living marine resources including the ecological and economic costs and trade-offs of different spatial management strategies. Given the strengths and weaknesses of the various types of models reviewed here, confidence in projections of changes in the distribut

Face aux enjeux de compréhension des écosystèmes marins et de gestion des usages marins, les modèles complexes se révèlent des outils pertinents pour tester les modifications induites par le changement global, anticiper des évolutions des socio-écosystèmes marins et aider à la sélection de stratégies de gestion. Construire un modèle numérique et faire des simulations est une chose, mesurer la confiance des sorties du modèle en est une autre. Une étape indispensable dans l'usage des modèles numériques est la confrontation des sorties du modèle aux observations du système modélisé pour caler le modèle. La sélection de stratégies de gestion et la calibration sont deux finalités de l'optimisation. Les problèmes d'optimisation en modélisation halieutique sont le plus souvent complexes avec des caractéristiques mathématiques diverses. La fonction à optimiser peut être déterministe ou stochastique, avec ou sans contraintes, à une ou plusieurs dimensions. Le nombre de paramètres à optimiser peut varier de l'unité à plusieurs centaines et le coût informatique peut induire de fortes restrictions sur le nombre de simulations réalisables avec le modèle, d'une centaine à quelque milliers pour les moins coûteux. Aucun guide pratique n'est disponible dans la littérature pour mettre en oeuvre une optimisation rigoureuse avec un modèle complexe. Nous proposons ici une démarche d'optimisation articulée en 3 étapes (prétraitement, choix de l'algorithme et post-traitement), basée des outils et méthodes existants et dont la réalisation peut être non linéaire. Ce guide inspiré d'une analyse des expériences d'un groupe de modélisateurs ouvre des pistes de recherche pour pallier aux difficultés, aux autocensures et frustrations des modélisateurs.

Face aux enjeux de compréhension des écosystèmes marins et de gestion des usages marins, les modèles complexes se révèlent des outils pertinents pour tester les modifications induites par le changement global, anticiper des évolutions des socio-écosystèmes marins et aider à la sélection de stratégies de gestion. Construire un modèle numérique et faire des simulations est une chose, mesurer la confiance des sorties du modèle en est une autre. Une étape indispensable dans l'usage des modèles numériques est la confrontation des sorties du modèle aux observations du système modélisé pour caler le modèle. La sélection de stratégies de gestion et la calibration sont deux finalités de l'optimisation. Les problèmes d'optimisation en modélisation halieutique sont le plus souvent complexes avec des caractéristiques mathématiques diverses. La fonction à optimiser peut être déterministe ou stochastique, avec ou sans contraintes, à une ou plusieurs dimensions. Le nombre de paramètres à optimiser peut varier de l'unité à plusieurs centaines et le coût informatique peut induire de fortes restrictions sur le nombre de simulations réalisables avec le modèle, d'une centaine à quelque milliers pour les moins coûteux. Aucun guide pratique n'est disponible dans la littérature pour mettre en oeuvre une optimisation rigoureuse avec un modèle complexe. Nous proposons ici une démarche d'optimisation articulée en 3 étapes (prétraitement, choix de l'algorithme et post-traitement), basée des outils et méthodes existants et dont la réalisation peut être non linéaire. Ce guide inspiré d'une analyse des expériences d'un groupe de modélisateurs ouvre des pistes de recherche pour pallier aux difficultés, aux autocensures et frustrations des modélisateurs.

In the past decade, systematic conservation planning tools have been increasingly and successfully used to set spatial conservation plans that meet quantitative protection targets while minimizing enforcement and socioeconomic costs. However, when applied to fisheries, systematic conservation planning fails to account for (1) changes in fleet dynamics induced by new conservation constraints and their associated feedbacks on conservation costs or (2) their influence on fish population dynamics and distributions, which may in turn alter the achievement of conservation targets. Such a static approach may therefore lead to short- or medium-term misestimates in forecasted costs and target achievements. In order to circumvent such limitations of systematic conservation planning, we present a first attempt to couple a conservation planning tool (Marxan with Zones) with a mixed fisheries dynamics simulation model (ISIS-Fish), applied to the Eastern English Channel fisheries. Broad principles and perspectives are discussed and anticipated future challenges of such an approach are presented.

In the past decade, systematic conservation planning tools have been increasingly and successfully used to set spatial conservation plans that meet quantitative protection targets while minimizing enforcement and socioeconomic costs. However, when applied to fisheries, systematic conservation planning fails to account for (1) changes in fleet dynamics induced by new conservation constraints and their associated feedbacks on conservation costs or (2) their influence on fish population dynamics and distributions, which may in turn alter the achievement of conservation targets. Such a static approach may therefore lead to short- or medium-term misestimates in forecasted costs and target achievements. In order to circumvent such limitations of systematic conservation planning, we present a first attempt to couple a conservation planning tool (Marxan with Zones) with a mixed fisheries dynamics simulation model (ISIS-Fish), applied to the Eastern English Channel fisheries. Broad principles and perspectives are discussed and anticipated future challenges of such an approach are presented.

Cet ouvrage donne une vision globale des différents modèles d’analyse de sensibilité et d’exploration des modèles développés en océanographie, environnement, gestion de l’eau, écologie, agronomie… Il propose une démarche permettant de choisir la méthode la plus adaptée à son besoin et montre concrètement comment appliquer ces méthodes. Il s’adresse aux modélisateurs et utilisateurs de modèles qui souhaitent acquérir ou consolider leur maîtrise des méthodes d’analyse et d’explorations des modèles par simulations.

Cet ouvrage donne une vision globale des différents modèles d’analyse de sensibilité et d’exploration des modèles développés en océanographie, environnement, gestion de l’eau, écologie, agronomie… Il propose une démarche permettant de choisir la méthode la plus adaptée à son besoin et montre concrètement comment appliquer ces méthodes. Il s’adresse aux modélisateurs et utilisateurs de modèles qui souhaitent acquérir ou consolider leur maîtrise des méthodes d’analyse et d’explorations des modèles par simulations.

Cet ouvrage donne une vision globale des différents modèles d’analyse de sensibilité et d’exploration des modèles développés en océanographie, environnement, gestion de l’eau, écologie, agronomie… Il propose une démarche permettant de choisir la méthode la plus adaptée à son besoin et montre concrètement comment appliquer ces méthodes. Il s’adresse aux modélisateurs et utilisateurs de modèles qui souhaitent acquérir ou consolider leur maîtrise des méthodes d’analyse et d’explorations des modèles par simulations.