Les espaces de l'halieutique

Le poulpe commun (#Octopus vulgaris) est très abondant au large des côtes NO-africaines où il est exploité à grande échelle. En Mauritanie, il représente la principale ressource halieutique grâce à la production de la zone de pêche du Cap-Blanc. Les caractéristiques globales de répartition spatio-temporelle de la population d'#Octopus vulgaris présent dans cette zone (20°30 N, nord de la Mauritanie) sont décrites à partir de données de chalutages scientifiques réalisés au cours de 24 campagnes mensuelles effectuées de mai 1993 à avril 1995. On constate que des poulpes de différents sexes, tailles (âges) et stades de maturité sont présents, quel que soit le mois et quelle que soit la profondeur (entre 10 et 100 m). Des phénomènes cycliques existent néanmoins à l'échelle de cette population. Ils se manifestent autant par des variations saisonnières et bathymétriques dans les proportions des différentes composantes précitées que par leurs variations d'abondances absolues. Ainsi le recrutement, qui est continuel, est structuré par deux pics principaux par an (juin et période autonmnale) de même que la ponte (septembre et période hivernale). A part cela, on ne retrouve pas en Mauritanie la trace de migrations génésiques saisonnières telles que décrites en zone tempérée pour cette même espèce. Le schéma observé ici est plutôt celui d'une stratégie d'occupation permanente du milieu, et en particulier des différentes strates bathymétriques, par les différentes composantes de la population. (Résumé d'auteur

Les espaces de l'halieutique

Le pulpe #Octopus vulgaris$ est abondant sur les fonds côtiers de la Petite Côte du Sénégal où sa répartition serait plus liée à la disponibilité des proies qu'à d'autres facteurs environnementaux. L'abondance des jeunes devient très importante en été et la pêche artisanale exploite alors préférentiellement cette ressource à partir de deux sites portuaires principaux situés à environ 35 km de distance, Mbour au nord et Joal au sud. Les sorties des pirogues sont journalières et l'engin de pêche, la turlutte à poulpe, d'un type très particulier à la pêche sénégalaise, fait appel au comportement de l'espèce. La pêche commence plus tard à Joal qu'à Mbour, avec dès son début des rendements plus élevés, et se termine plus tôt. Il y a peu de déplacements de pêcheurs venant de Mbour ou d'ailleurs, mais une conversion massive à la pêche au poulpe des pirogues recherchant habituellement d'autres espèces, en particulier les pirogues à filet maillant encerclant pour la capture des sardinelles. Les fonds de pêche inférieurs à 10 mètres sont plutôt exploités en début de saison et ceux supérieurs à 25 mètres et plus éloignés en fin, ce qui peut traduire un mouvement migratoire lent du poulpe ou/et une optimisation économique des sorties de pêche. (Résumé d'auteur

Pêcheries au cœur d'un enjeu de développement : les pêcheries démersales Mauritaniennes du poulpe et des crevettes côtières : confrontation entre stratégies des acteurs : éléments d'analyse

Comme dans la plupart des pêcheries, certaines questions relatives à l'allocation des moyens d'exploitation (moyens compris au sens large, englobant l'accès à la ressource biologique, les moyens financiers, les structures, etc.) se posent aux pêcheries démersales Mauritaniennes: ici, les problèmes d'allocation s'expriment, en particulier entre armements industriels et artisanaux d'une part (cas du poulpe), et entre armements industriels étrangers et nationaux d'autre part (cas de l'exploitation des crevettes côtières). A partir de l'exemple de certaines mesures de gestion prises par l'Etat, ce travail essaie d'en analyser l'impact sur la dynamique de ces pêcheries. Il montre comment, en retour, cette dynamique - et la réaction des différents acteurs privés faces aux actions institutionnelles -peut conduire l'Etat à réajuster ses stratégies. Il ressort également que les mesures prises par l'Etat, sous une certaine logique économique, peuvent s'avérer contradictoires dans leurs effets. Un exemple de ce type de contradiction est donné dans le cas de la pêche aux crevettes côtières. De même, les stratégies des acteurs intervenant directement ou indirectement dans l'exploitation du poulpe en Mauritanie sont mises en lumière. Sont illustrés différents exemples sur les processus de confrontation et de négociation qui aboutissent à une plus grande implication des différents groupes d'acteurs en présence: comme par exemple, à propos du contrôle des institutions et associations de la pêche artisanale, structures mises en place par l'Etat mais dont il a perdu une part du contrôle. Globalement, les évolutions des modes d'organisation sociale de la production, les dynamiques de l'exploitation, les changements de comportement et de mentalité qui sont à l’œuvre dans la pêcherie démersale mauritanienne sont analysés en rapport avec les dynamiques des modes de régulation institutionnels. On en déduit que tout ce qui concerne l'aménagement primaire a abouti à un échec (par évitement des mesures) alors que, pour le reste, les structures régulatrices mises en place par l'Etat ont un bilan assez positif (même si elles ont connu une histoire conflictuelle jalonnée de confrontations/négociations). L'échec des mesures primaires est attribué principalement à une absence de politique claire de régulation de l'accès ainsi qu'à une mauvaise prise en compte des principales interactions entres les différentes flottilles et groupes d'exploitants

STRING: known and predicted protein–protein associations, integrated and transferred across organisms

A full description of a protein's function requires knowledge of all partner proteins with which it specifically associates. From a functional perspective, ‘association’ can mean direct physical binding, but can also mean indirect interaction such as participation in the same metabolic pathway or cellular process. Currently, information about protein association is scattered over a wide variety of resources and model organisms. STRING aims to simplify access to this information by providing a comprehensive, yet quality-controlled collection of protein–protein associations for a large number of organisms. The associations are derived from high-throughput experimental data, from the mining of databases and literature, and from predictions based on genomic context analysis. STRING integrates and ranks these associations by benchmarking them against a common reference set, and presents evidence in a consistent and intuitive web interface. Importantly, the associations are extended beyond the organism in which they were originally described, by automatic transfer to orthologous protein pairs in other organisms, where applicable. STRING currently holds 730 000 proteins in 180 fully sequenced organisms, and is available at http://string.embl.de/

Strong fisheries management and governance positively impact ecosystem status

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.IOC-UNESCO; EuroMarine; European FP7 MEECE research project; European Network of Excellence Eur-Oceans; FRB EMIBIOS project [212085]info:eu-repo/semantics/publishedVersio

The demersal fisheries of Mauritaniua in 2003: description of the fleets and assessment of resources: First report of a joint IMROP/RIVO project

Demersal fisheries in the Mauritanian Exclusive Economic Zone (EEZ) are described, with a review of the state of the stocks that are exploited by these fisheries. The assessment of the various stocks is based primarily on the results of the “Groupe de Travail” (GT), held in December 2002 at the Mauritanian fisheries research institute IMROP, Nouadhibou. The conclusions of these assessments are that the octopus stock in the Mauritanian EEZ is overexploited and that fishing effort is about 30% above the optimum level. Shrimps appear to be exploited near their maximum level. Fishing mortality on hake should be reduced, and the fishing effort in the roundfish fleet should not be further increased

Long-term fishing impact on the Senegalese coastal demersal resources: diagnosing from stock assessment models

For the first time in Senegal, assessments based on both stochastic and deterministic production models were used to draw a global diagnosis of the fishing impact on coastal demersal stocks. Based one national fisheries databases and scientific trawl surveys data: (i) trends in landings since 1971 were examined, (ii) abundance indices of 10 stocks were estimated using linear models fitted to surveys data and commercial catch per unit efforts, and (iii) stock assessments were carried out using pseudo-equilibrium Fox and Pella-Tomlinson models and a Biomass dynamic production model fitted in a Bayesian framework to abundance indices. Most stocks have seen their abundance sharply declining over time. All stocks combined, results of stock assessments suggest a 63% reduction compared to virgin state. Three fifth of demersal stocks are overexploited and excess in fishing effort was estimated until 75% for the worst case. We conclude by suggesting that the fishing of such species must be regulated and an ecosystem approach to fisheries management should be implemented in order to monitor the whole ecosystem

Scientific Advice on the estimation of surplus for Sustainable Fisheries Partnership Agreements.

Scientific advice on the concept of surplus, as defined by the UNCLOS, was provided for three types of Sustainable Fisheries Partnership Agreements (SFPAs): i) Mixed SFPAs in West Africa, ii) Tuna SFPAs and iii) SFPA with Greenland. For Mixed SFPAs in West Africa, methods for surplus computation were defined, including alternatives for cases of data limited stocks. These methods may use as input five parameters that could be obtained from those recent stocks assessments that are representative of the current stock status. Surplus estimates would need to be regularly updated (ideally, yearly), according to every new stock assessments and following the enforcement of a management plan (or, by default, according to a transition scheme towards reaching Fmsy in 2020). In the case of West African transboundary stocks, a theoretical share of the surplus could be calculated using a standard rule based on historical catches within EEZs. The Surplus concept is not applicable for Tuna SFPAs, due to the high migratory character of tuna or tuna-like species, the fact that these stocks are mostly found in areas beyond national jurisdictions, the lack of direct estimates of local abundance and impossibility to calculate the capacity of the coastal States. For the SFPA with Greenland, Surplus is considered as any TAC allocated to Greenland and not utilised by this coastal State

Strong fisheries management and governance positively impact ecosystem status

Bundy, Alida ... et al.-- 28 pages, 6 figures, 8 tables, supporting information https://dx.doi.org/10.1111/faf.12184Fisheries 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 togetherThis 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)Peer Reviewe