![]() | Perspectives de developpement des DCP ancres dans les Petites Antilles. L'exemple de trois iles: Guadeloupe, Martinique et Curacao Auteur(s) : Reynal, Lionel Van Buurt, G Taquet, Marc Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : This summary tackles the development of fisheries in the Caribbean using fads. It highlights the principal causes which explain why, in spite of more than thirty years of experimenting, fishing on fads has not developed as much as had been hoped. Whereas the deep-sea production of pelagic fish by the continental countries of the region has considerably increased since the early eighties, that of the Lesser Antilles has grown more slowly. Anchored fads have given the boats of the small-scale fisheries from three islands (Guadeloupe, Martinique and Curacao) access to these pelagic resources. The various modes of development and management of the fads observed in each island are described. The first available data are used to provide some indications of the effects of the various strategies implemented and the changes induced by this new fishing technique.Original Abstract: Cette synthese concerne la region Atlantique Centre-Ouest (FAO 31) mais elle aborde principalement le developpement des DCP ancres de la zone Caraibe. Trois sites principaux font l'objet d'un developpement particulier ; il s'agit des iles pour lesquelles l'activite de peche professionnelle est actuellement effective autour des DCP : la Guadeloupe, la Martinique et Curacao. L'introduction de DCP dans l'Atlantique Centre-Ouest est signalee pour la premiere fois en 1969, a Panama City (Floride). Il s'agit alors de dispositifs cotiers. Les especes ciblees sont des petits poissons pelagiques. Au debut des annees quatre-vingt, l'implantation de DCP ancres autour des petits etats insulaires de la Caraibe pour la peche des grands poissons pelagiques est consideree comme une priorite par les scientifiques reunis lors du 36e congres du Gulf and Caribbean Fisheries Institute (GCFI). Beaucoup d'experiences DCP conduites dans la region ont permis de conclure a une bonne efficacite agregative quels que soient les choix technologiques operes (DCP lourds ou legers). Malgre cela, tres peu d'iles tirent actuellement benefice de l'avantage que procurent les DCP pour l'exploitation des ressources en grands pelagiques frequentant leurs eaux. Les problemes de transfert et les difficultes a passer de la phase experimentale a la phase operationnelle sont probablement a l'origine de ce paradoxe. Le developpement d'une reelle cooperation regionale sur le theme devrait permettre, aux petits etats insulaires notamment, de mieux profiter des migrations des grands poissons pelagiques dans leurs eaux. Droits : Ifremer http://archimer.ifremer.fr/doc/00042/15279/12665.pdf http://archimer.ifremer.fr/doc/00042/15279/ | Partager Voir aussi Artisanal fishing Attracting techniques Pelagic fisheries Article Geographic Terms: Caribbean Region Télécharger |
![]() | A stochastic viability approach to ecosystem-based fisheries management Auteur(s) : Doyen, Luc Thebaud, Olivier Bene, Christopher Martinet, V. Gourguet, S. Bertignac, Michel Fifas, Spyros Blanchard, Fabian Éditeur(s) : Elsevier Science Bv Résumé : Academia and management agencies show a growing interest for ecosystem-based fishery management (EBFM). However, the way to operationalize this approach remains challenging. The present paper illustrates how the concepts of stochastic co-viability, which accounts for dynamic complexities, uncertainties, risk and sustainability constraints, can be useful for the implementation of EBFM. In the present case, this concept is used to identify fishing strategies that satisfy both ecological conservation and economic sustainability in a multi-species, multi-fleet context. Economic Viability Analysis (EVA) and the broader Co-Viability Analysis (CVA), are proposed to expand the usual Population Viability Analysis (PVA) and precautionary approach. An illustration is proposed, using data on the fisheries of Bay of Biscay (France) exploiting the stocks of nephrops and hake. Stochastic simulations show how CVA can guarantee both ecological (stock) and economic (profit) sustainability. Using 2008 as a baseline, the model is used to identify fishing efforts that ensure such co-viability. (C) 2012 Elsevier B.V. All rights reserved. Ecological Economics (0921-8009) (Elsevier Science Bv), 2012-03 , Vol. 75 , P. 32-42 Droits : 2012 Elsevier Science Bv http://archimer.ifremer.fr/doc/00074/18571/16153.pdf DOI:10.1016/j.ecolecon.2012.01.005 http://archimer.ifremer.fr/doc/00074/18571/ | Partager |
![]() | Collaborative research: Development of a manual on elasmobranch handling and release best practices in tropical tuna purse-seine fisheries Auteur(s) : Poisson, Francois Seret, Bernard Vernet, Anne-lise Goujon, Michel Dagorn, Laurent Éditeur(s) : Elsevier Sci Ltd Résumé : The reduction of by-catch mortality is an objective of the ecosystem approach to fisheries and a request made by consumers. Elasmobranchs, an important component of the French tropical tuna purse seine fishery by-catch, are currently thrown back into the sea. Fishers interact with various types of elasmobranchs that range widely in size, weight and shape, and could pose various degrees of danger to the crew. A diversity of discarding practices within the fleet were reported, some practices were considered suitable, others needed to be adapted and improved and others simply had to be banned. The majority of the crews were likely to improve their handling practices if they were presented with practical suggestions that were quick and easy. Combining scientific observations and empirical knowledge from skippers and crew, a manual, providing appropriate handling practices to ensure crew safety and increase the odds of survival for released animals has been developed and disseminated. Bringing these good practices onto the decks of fishing vessels should contribute to the reduction of the fishing mortality of some vulnerable species. It would be positively viewed by consumers as an act that reduces fishing's footprint on the environment and promoting animal welfare which would improve the image of fishing industry. Mitigation research is by definition an iterative process and different complementary methods must be carried out at different levels of the fishing process to significantly reduce the mortality of the by-catch. Marine Policy (0308-597X) (Elsevier Sci Ltd), 2014-02 , Vol. 44 , P. 312-320 Droits : 2013 Elsevier Ltd. All rights reserved. http://archimer.ifremer.fr/doc/00159/27008/28367.pdf DOI:10.1016/j.marpol.2013.09.025 http://archimer.ifremer.fr/doc/00159/27008/ | Partager |
![]() | Méthodes MCMC en interaction pour l'évaluation de ressources naturelles Auteur(s) : Campillo, Fabien Cantet, Philippe Rakotozafy, Rivo Rossi, Vivien Auteurs secondaires : Water Resource Modeling (MERE) ; Inria Sophia Antipolis - Méditerranée (CRISAM) ; Institut National de Recherche en Informatique et en Automatique (Inria) - Institut National de Recherche en Informatique et en Automatique (Inria) - Institut National de la Recherche Agronomique (INRA) Ouvrages hydrauliques et hydrologie (UR OHAX) ; CEMAGREF Université de Fianarantsoa [Fianarantsoa] Ecologie des forêts de Guyane (ECOFOG) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD) - Institut National de la Recherche Agronomique (INRA) - Université des Antilles et de la Guyane (UAG) - AgroParisTech - Centre National de la Recherche Scientifique (CNRS) Éditeur(s) : HAL CCSD INRIA Résumé : International audience Markov chain Monte Carlo (MCMC) methods together with hidden Markov models are extensively used in the Bayesian inference for many scientific fields like environment and ecology. Through simulated examples we show that the speed of convergence of these methods can be very low. In order to improve the convergence properties, we propose a method to make parallel chains interact. We apply this method to a biomass evolution model for fisheries. Les méthodes de Monte Carlo par chaînes de Markov (MCMC) couplées à des modèles de Markov cachés sont utilisées dans de nombreux domaines, notamment en environnement et en écologie. Sur des exemples simples, nous montrons que la vitesse de convergence de ces méthodes peut être très faible. Nous proposons de mettre en interaction plusieurs algorithmes MCMC pour accélérer cette convergence. Nous appliquons ces méthodes à un modèle d'évolution de la biomasse d'une pêcherie. ISSN: 1638-5713 inria-00506386 https://hal.inria.fr/inria-00506386 https://hal.inria.fr/inria-00506386/document https://hal.inria.fr/inria-00506386/file/campillo2008d.pdf | Partager |
![]() | Patrimoine marin caribéen et perspectives écotouristiques : vers un développement durable des petites îles ? Auteur(s) : Augier, Dominique Éditeur(s) : Université des Antilles Études caribéennes Résumé : La mer des Caraïbes abrite une diversité de biotopes littoraux qui favorisent l’installation de trois écosystèmes - les récifs coralliens, les mangroves et les herbiers – riches et complexes. On y trouve également d’autres formations uniques tels les stromatolithes ou les trous bleus. Des conditions climatiques et océanographiques homogènes permettent à l’ensemble du bassin Caraïbe de constituer une unité sur les plans floristique et faunistique. Cette unité n’exclut pas une diversité biologique exceptionnelle avec notamment des espèces endémiques à la zone ; ce qui confère aux côtes des pays caribéens un intérêt écologique, paysager et scientifique certain. La reconnaissance sur le plan international et régional de l’importance de la Mer des Caraïbes mais aussi de sa fragilité a permis au milieu marin caribéen d’acquérir son statut de patrimoine naturel.En plus des services écosystémiques qu’elle rend (ressources halieutiques, protection des littoraux…), la Mer des Caraïbes constitue un atout indéniable dans le cadre du développement touristique de la zone aussi bien par le balnéaire que, plus récemment, par l’écotourisme. Ce dernier s’appuie généralement sur des aires marines protégées et doit permettre un développement durable des îles.A partir d’une étude de cas, le parc marin de Saba, l’objectif de cette étude est d’analyser les rapports entre patrimoine naturel marin et l’écotourisme, ainsi que les impacts économiques, sociaux et environnementaux de la mise en valeur de ces ressources. The Caribbean Sea is home to a diversity of coastal habitats that support the installation of three rich and complex ecosystems - coral reefs, mangroves and seagrasses -. There are also other unique formations such as stromatolites or blue holes. Oceanographic and climatic conditions allow homogeneous throughout the Caribbean basin to form a unit in terms of flora and fauna. This unit does not exclude an exceptional biological diversity, including species endemic to the area, which give the coasts of the Caribbean countries an ecological, landscape and some science. Recognition on the international and regional importance of the Caribbean Sea but also its fragile marine environment has allowed the Caribbean to gain its status as a natural heritage.In addition to the ecosystem services it render (fisheries, coastal protection ...), the Caribbean Sea is a definite asset in the development of tourism in the area by the seaside as well as, more recently, ecotourism. The latter is generally based on marine protected areas and should facilitate the sustainable development of islands.From a case study, the Saba Marine Park, the objective of this study is to analyze the relationship between natural heritage and marine ecotourism, as well as economic, social and environmental development of these resources. Saba Droits : info:eu-repo/semantics/openAccess urn:doi:10.4000/etudescaribeennes.5487 http://journals.openedition.org/etudescaribeennes/5487 | Partager |
![]() | A bio-economic analysis of long term changes in the production of French fishing fleets operating in the Bay of Biscay Auteur(s) : Steinmetz, Fabien Thebaud, Olivier Blanchard, Fabian Le Floc H, Pascal Bihel, J Éditeur(s) : EDP Sciences Résumé : Selective fishing pressure on more highly valued marine living resources is one of the key factors proposed to explain changes occurring in fish communities and associated landings of commercial fisheries. The aim of this paper is to establish the nature of changes in the landings of French fishing fleets operating in the Bay of Biscay in the period 1973-2002, and whether these changes could be related to the relative economic attractiveness of different fish species. The analysis focuses on trends observed in the landings of all commercial fish species over the last three decades. It is based on data of annual quantities landed and ex-vessel prices compiled from official French landings records, and on bio-geographical descriptors of these species derived from published data. Using simple index numbers and multivariate analysis, we examined changes in total landings in terms of their volume and value, as well as changes in their composition. We show that the composition of landings significantly changed over the study period, with an increase in the proportion of pelagic species, of lower economic value. The average ex-vessel price of production by the fleets tended to decrease from the late 1980s; partly due to a cross-species drop in prices, occurring mainly after 1993, but also to the increased proportion of low-priced species in the landings. This caused a significant drop in the total gross value of production in the second half of the study period. La pression de pêche sélective sur les ressources marines vivantes de forte valeur est un des facteurs-clés proposés pour expliquer les changements qui surviennent dans la structure des communautés de poisson et dans les débarquements des pêcheries commerciales associés. L'objectif de cet article est d'établir la nature des changements dans les débarquements des flottilles de pêche françaises opérant dans le golfe de Gascogne, et d'examiner les relations entre ces changements et l'attractivité relative des espèces de poisson d'un point de vue économique. L'analyse se concentre sur les tendances observées au cours des trois dernières décennies dans les débarquements de toutes les espèces commerciales de poissons effectués par les flottilles de pêche opérant dans le golfe. Elle s'appuie sur des données concernant les quantités annuelles débarquées, les prix compilés à partir des enregistrements officiels des débarquements français, et les données publiées concernant les caractéristiques biogéographiques des espèces étudiées. En s'appuyant sur des indices simples et une analyse multivariée, on examine les changements des débarquements totaux en volume et en valeur, ainsi que les changements dans leur composition. On montre que la composition des débarquements a fortement changé au cours de la période étudiée, avec un accroissement important de la part des espèces pélagiques, de plus faible valeur. Le prix moyen de la production a eu tendance à décroître depuis la fin des années 1980. Ceci est en partie dû à une chute des prix de l'ensemble des espèces, après 1993, et en partie lié à l'accroissement de la part des espèces de plus faible valeur dans les débarquements. Une baisse importante de la valeur de la production en a découlé sur cette deuxième moitié de la période d'étude. Aquatic Living Resources (0990-7440) (EDP Sciences), 2008-07 , Vol. 21 , N. 3 , P. 317-327 Droits : 2008 EDP Sciences http://archimer.ifremer.fr/doc/2008/publication-5926.pdf DOI:10.1051/alr:2008048 http://archimer.ifremer.fr/doc/00000/5926/ | Partager Voir aussi North Eastern Atlantic Bay of Biscay Long term changes Bio economic analysis French fisheries production Télécharger |
![]() | The use of anchored FADs in the area served by the Secretariat of the Pacific community (SPC): Regional synthesis Auteur(s) : Desurmont, A Chapman, L Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 15-19 octobre 1999 Résumé : In the area served by the Secretariat of the Pacific Community (SPC), which includes 22 Pacific Island countries and territories, anchored FADs have been used since the late 1970s. First introduced from the Philippines, via Hawaii, they were quickly adopted by both industrial and artisanal fisheries sectors : in 1984 more than 600 anchored FADs had been deployed in the region. Since these early days, the development of the technique by the industrial and the artisanal sectors have followed parallel paths with little interaction. In the industrial private sector, companies are funding, deploying and monitoring their own FADs. For some fishing companies, using purse seiners and pole-and-line vessels, from the Solomon Islands or Papua-New-Guinea, these FADs have become a necessity. FAD programmes for small-scale fisheries have been almost exclusively run by the public sector, with technical support from regional and international development agencies and financial assistance from overseas funding agencies. These programmes have had mixed successes : becoming an on-going and essential tool in some places like French Polynesia or Guam; or being momentarily suspended, like in Vanuatu or Tonga, because of the lack of funds, partly due to the scarcity of proven economic return to the fishing communities. This document is an attempt to synthesise the current information on these very diverse situations, including technical, economical and social considerations. Droits : Ifremer http://archimer.ifremer.fr/doc/00042/15283/12669.pdf http://archimer.ifremer.fr/doc/00042/15283/ | Partager |
![]() | Nutrient dynamics, primary production and fisheries yields of lagoons Auteur(s) : Nixon, S W Éditeur(s) : Gauthier-Villars Résumé : Differences appear to have a marked influence on the species composition of lagoon ecosystems around the world, but there are some remarkable similarities in nutrient dynamics, the standing crop of phytoplankton, annual primary production, and fisheries yields of many lagoons. For example, in many of the systems reviewed, the annual phosphate cycle was similar in timing and magnitude, primary production amounted to some 200-400 g C m super(-1) yr super(-1). There appears to be an empirical correlation between primary production and fisheries yields in a great variety of marine systems. The yield of lagoon fisheries per unit area is commonly as high or higher than that from the most productive coastal and offshore fisheries. Oceanologica Acta, Special issue (0399-1784) (Gauthier-Villars), 1982 Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00246/35748/34256.pdf http://archimer.ifremer.fr/doc/00246/35748/ | Partager |
![]() | Manuel des Pêches Maritimes Françaises - Fascicule IV Auteur(s) : Beauge, L Belloc, G Boury, M Desbrosses, P Face, L Le Gall, J Lambert, L Remy, D Éditeur(s) : Office scientifique et technique des pêches maritimes Résumé : This fourth part deals with the following points: - Industries related to fishing: - Curing, salting and canning - Processing of by-products - Refrigeration - Processing of seaweed - Oyster farming, mussel farming and shellfish farming - General survey of maritime fishing regulation in France Cette version du Manuel des Pêches Maritimes françaises a été éditée en 1936 par l'Office des Pêches Maritimes. Les auteurs ont essayé de préciser quelle était alors la situation technique de l'industrie à laquelle étaient consacrées leurs études. Ce quatrième fascicule traite des points suivants: - Les Industries annexes de la pêche : - Fumage, Salage et Conserve - Traitement des sous-produits - Frigorification - Traitement des Algues marines - L'Ostréiculture, la Mytiliculture et la Conchylicultrice - Aperçu sur la réglementation de la pêche maritime en France Mémoires de l'Office des Pêches Maritimes (1245-558X) (Office scientifique et technique des pêches maritimes), 1936-04 , Vol. Série spéciale , N. 12 fasc.4 Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1936/rapport-1738.pdf http://archimer.ifremer.fr/doc/00000/1738/ | Partager |
![]() | Biogeography of tuna and billfish communities Auteur(s) : Reygondeau, Gabriel Maury, Olivier Beaugrand, Gregory Fromentin, Jean-marc Fonteneau, Alain Cury, Philippe Éditeur(s) : Wiley-blackwell Résumé : Aim The aims of this study were: (1) to identify global communities of tuna and billfish species through quantitative statistical analyses of global fisheries data; (2) to describe the spatial distribution, main environmental drivers and species composition of each community detected; and (3) to determine whether the spatial distribution of each community could be linked to the environmental conditions that affect lower trophic levels by comparing the partitions identified in this study with Longhursts biogeochemical provinces. Location The global ocean from 60 degrees S to 65 degrees N. Methods We implemented a new numerical procedure based on a hierarchical clustering method and a nonparametric probabilistic test to divide the oceanic biosphere into biomes and ecoregions. This procedure was applied to a database that comprised standardized data on commercial longline catches for 15 different species of tuna and billfish over a period of more than 50 years (i.e. 1953-2007). For each ecoregion identified (i.e. characteristic tuna and billfish community), we analysed the relationships between species composition and environmental factors. Finally, we compared the biogeochemical provinces of Longhurst with the ecoregions that we identified. Results Tuna and billfish species form nine well-defined communities across the global ocean. Each community occurs in regions with specific environmental conditions and shows a distinctive species composition. High similarity (68.8% homogeneity) between the spatial distribution of the communities of tuna and billfish and the biogeochemical provinces suggests a strong relationship between these species and the physical and chemical characteristics of the global ocean. Main conclusions Despite their high tolerance for a wide range of environmental conditions, these highly migratory species are partitioned into clear geographical communities in the ocean at a global scale. The similarity between biogeochemical and biotic divisions in the ocean suggests that the global ocean is a mosaic of large biogeographical ecosystems, each characterized by specific environmental conditions that have a strong effect on the composition of the trophic web. Journal Of Biogeography (0305-0270) (Wiley-blackwell), 2012-01 , Vol. 39 , N. 1 , P. 114-129 Droits : 2011 Blackwell Publishing Ltd http://archimer.ifremer.fr/doc/00060/17141/14716.pdf DOI:10.1111/j.1365-2699.2011.02582.x http://archimer.ifremer.fr/doc/00060/17141/ | Partager Voir aussi Biogeochemical provinces global ocean Istiophorus Katsuwonus macroecology Makaira marine biogeography Tetrapturus Thunnus Xiphias Télécharger |
![]() | Le " faux-poisson " d'Abidjan et la peche sous DCP derivants dans l'Atlantique tropical Est: circuit de commercialisation et role socio-economique Auteur(s) : Romagny, B Menard, Frederic Dewals, P Gaertner, Daniel N'Goran, N Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : Abidjan is the biggest fishing harbour of tropical tunas in the Gulf of Guinea (around 100 000 mt per year). Three canneries work on four species (yellowfin, skipjack, bigeye and albacore). Small size tuna, minor tuna and by-catches are refused by the canneries and are sold on the local market fish. It is the only part of the industrial purse seine catches directly sold in Abidjan. Since 1990, fishing operations on schools of tuna associated with artificial drifting FADs has become widespread. Log fishery allow to catch a majority of small tunas, and generates by-catches of various other pelagic species associated to the logs. The landed amounts of local market fish have increased: from 8 500 Mt per year estimated between 1987 and 1990, 21 000 Mt is reached between 1991 and 1993. Since 1994, controls have been carried out by French fishing companies. A sampling scheme allows us to analyse precisely the landings since 1998. From an interdisciplinary approach, we study the socio-economic role of this local fish market, especially the links between the different actors on this market, and we analyse his impact on fishing strategies by identifying the distribution networks (actors, prices, profit) and estimating the turnovers connected to this sector. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15318/12642.pdf http://archimer.ifremer.fr/doc/00042/15318/ | Partager |
![]() | Evolution technologique des DCP en Polynesie francaise Auteur(s) : Leproux, E Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : French Polynesia started it's Fish Aggregating Device programme in June 1981 with the positioning of the first buoy offshore of the main island of Tahiti. Since then, 251 structures have been installed throughout the 5 archipelagoes of this French overseas territory. The shape and size of the devices have evolved 8 times over this period, however, a single model has not yet been adopted. Trials are currently underway using lighter structures similar to those found in the Indian Ocean. The anchoring lines have progressively been modified through better knowledge of material and product availability, as well as better understanding of environmental constraints. The programme is entirely financed by the territorial government and managed by the public sector. This ongoing technical assistance, aimed towards the local small-scale coastal fishery, is considered an important factor to maintaining this activity alive. Up until 1997, this economical support policy of outer island populations far from the metropolis central town, along with incidental fishing methods around FADs, have given mitigated results without nevertheless putting into cause this programme. The use of 'drifting handlines' retained at the surface by small indicator floats are one of the contributing factors to the degradation of the anchor lines. It is now commonly accepted that a new fishing strategy must be adopted so that professional coastal fishermen become more aware with regards to an expensive work tool due to local bathymetric conditions, so that fishing effort is increased through the development of better adapted fishing techniques, and finally so that community spirit rules over individualism.Original Abstract: Le programme d'ancrage de DCP en Polynesie francaise a vu le jour en juin 1981 avec l'implantation d'un premier dispositif au large des cotes de Tahiti. Depuis cette date, ce sont 251 structures qui ont ete installees dans les cinq archipels de ce pays d'outre-mer. La forme et la taille des bouees ont evolue huit fois sans etre definitivement arretees a un seul modele et des essais sur des structures legeres de type " Ocean Indien " sont en cours. Les lignes d'ancrage ont fait l'objet de modifications progressives en raison de meilleures connaissances des produits ainsi que des contraintes du milieu environnant. Ce programme est finance en totalite par le territoire de la Polynesie francaise et gere par le secteur public. Il s'adresse a la pecherie artisanale et cotiere qui considere depuis de nombreuses annees cette assistance technique comme un atout indispensable au maintien de son activite. La politique d'engagement de ce soutien economique jusqu'en 1997 aupres des populations d'iles et atolls tres eloignes de la capitale ainsi que l'incidence de la technique de peche la plus repandue autour des DCP ont abouti a des resultats mitiges sans pour autant remettre en cause ce programme. En effet, les lignes a main derivantes et retenues en surface par une petite bouee temoin sont un des principaux facteurs de degradation des lignes d'ancrage. Il est desormais reconnu par tous les intervenants qu'une nouvelle strategie doit etre deployee afin que les pecheurs cotiers professionnels soient mieux responsabilises face a un outil de travail onereux en raison de la bathymetrie environnante, pour que l'effort de peche soit accru par l'utilisation de techniques de peche mieux adaptees, et enfin que l'esprit communautaire prime sur l'individualisme. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15292/12649.pdf http://archimer.ifremer.fr/doc/00042/15292/ | Partager |
![]() | Comparaison des captures des grands poissons pelagiques en Martinique avec ou sans DCP Auteur(s) : Laurans, Martial Taquet, Marc Reynal, Lionel Lagin, Alain-sabin Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : In recent years, the use of fads in Martinique has evolved from an experimental stage to a productive one. This transformation results in the pitching up of operational device park by the regional fishery committee. Nevertheless, this technical change in fishing practices is not implemented in a homogeneous way all around the island; some differences exist especially between the Atlantic and the Caribbean coasts. From surveys carried out during an annual cycle on two main landing sites, this study describes the pelagic fishing activity around fads and in the open sea. A comparison of fishing strategies adopted in different places as well as an analysis of the results obtained by the fishing units in terms of species (size of catches and daily yields) allow to describe the progress made in the implementation adoption of this new fishing practice. For several fishermen, fishing around fads has become an exclusive job, practised all year round. For others, fads is used in addition to traditional fishing activity on flotsam, "Miquelon" fishing and keeps a seasonal character.Original Abstract: Au cours des recentes annees, l'utilisation des DCP en Martinique est passee du stade experimental au stade operationnel. Cette mutation se traduit par la prise en charge du parc de dispositifs operationnels par le comite regional des peches. Toutefois, l'adoption de cette nouvelle technique d'exploitation ne s'effectue pas de facon homogene dans toutes les communes de l'ile, des differences existent notamment entre les cotes Atlantique et Caraibe. A partir d'enquetes effectuees pendant un cycle annuel, sur deux principaux points de debarquement, cette etude decrit l'activite de peche des poissons pelagiques avec ou sans DCP. Une comparaison des strategies de peche developpees dans les differents sites ainsi qu'une analyse des resultats obtenus par les unites de peche en termes d'especes, de taille des captures, de rendement journalier permettent de decrire la progression differenciee de l'adoption de cette nouvelle activite halieutique. Pour certains pecheurs, la peche sous DCP est devenue un metier exclusif, pratique tout au long de l'annee. Pour d'autres, le DCP est utilise en complement de l'activite traditionnelle de peche sous bois derivants, " peche a Miquelon ", et conserve un caractere saisonnier. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15298/12657.pdf http://archimer.ifremer.fr/doc/00042/15298/ | Partager |
![]() | Impact des mesures de gestion sur la dynamique de la pêcherie pélagique du golfe de Gascogne : Quelles certitudes ? Quels descripteurs ? ; Management impact on the pelagic fishery of the bay of Biscay : What is certain ? How to describe ? Auteur(s) : Lehuta, Sigrid Éditeur(s) : Agrocampus-ouest Résumé : Quantitative evaluations of management measure impact on resource and fleet viability are required to provide diagnostics and feed decision process. Fisheries are complex systems where numerous dynamics interact at various spatial and temporal scales. This complexity and the difficulty to observe marine systems are responsible for the high uncertainty surrounding fishery functioning that makes it hard to identify adequate management measures. The increasing consideration of uncertainties in diagnostics argues in favor of robust management measures rather than optimal management measures. Identifying robust management measures requires the development of models that account for complexity and uncertainty in the description and prediction of management impact as well as the identification of synthetic descriptors (indicators) of the state and dynamic of the system. The aim of this work is to propose generic methodologies for developing such tools. The methodological developments are applied to the pelagic fishery of the bay of Biscay. This fishery mainly focused on anchovy and was highly impacted by fishing ban on this species since 2005. Causes for anchovy drop in biomass either environmental or due to fishing are poorly understood, making management decision much harder in a critical environmental and economic context. The adequacy of traditional management using TAC is questioned and additional spatial management measures are proposed. Des évaluations quantitatives de l’impact de mesures de gestion sur les ressources et la viabilité des flottilles sont nécessaires pour établir des diagnostics et pour fournir des éléments d’orientation pour la gestion des pêcheries. Les pêcheries sont des systèmes complexes mettant en œuvre de nombreuses dynamiques à des échelles de temps et d’espace très variables et interagissant très fortement entre elles. Cette complexité et la difficulté d’observer les systèmes marins, conduit à une grande incertitude sur leur fonctionnement qui rend difficile la détermination des mesures de gestion adaptées. La reconnaissance de ces incertitudes, plaide de plus en plus en faveur d’une gestion robuste plutôt qu’optimale. Déterminer la robustesse des mesures de gestion nécessite le développement de modèles de description et de prédiction capable d’intégrer la complexité et l’incertitude du système, ainsi que d’outils de description synthétiques (indicateurs) de l’état et de la dynamique de la pêcherie à partir d’observations. L’objectif de ce travail est de proposer des méthodes génériques pour le développement de tels outils. Ces développements méthodologiques sont appliqués à la pêcherie pélagique du golfe de Gascogne. Cette pêcherie ciblant principalement l’anchois a été fortement perturbée par la fermeture de la pêche à cette espèce en 2005. Le déterminisme environnemental et le rôle de la pêche dans le déclin de la population d’anchois sont mal compris ce qui rend difficile la prise de décision dans un contexte économique et écologique critique. La gestion traditionnelle par TAC pourrait s’avérer insuffisante pour permettre l’exploitation durable et des mesures spatialisées sont envisagées en complément. Droits : 2010 The Author, UEB http://archimer.ifremer.fr/doc/00025/13630/10712.pdf http://archimer.ifremer.fr/doc/00025/13630/ | Partager |
![]() | The impact of FAD innovation on the performance of US tuna purse seine operations in the Pacific Ocean Auteur(s) : Sakagawa, G Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : It is generally accepted that innovations in tuna purse seine technology have affected fishing operations and the traditional measurement of fishing effort, days fished including searching time. Not much is known, however, about the actual effects of the innovations on fishing performance. Data from the us tuna purse seine fishery in the Western Pacific Ocean were used to determine the impact of drifting Fish Aggregating Devices (fads) on the performance of the us fleet. The results indicate, inter alia, a high rate of success (96%) in catching tuna and high yield rate (37 t/successful set) for fad sets. Log sets were comparable in success rate (94%) and catch rate (36 t/successful set). Unassociated sets, on the other hand, had a higher catch rate (42 t/successful set) than fad sets, but a low success rate, 53 per cent. fad sets significantly improved the fleet's performance. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15296/12655.pdf http://archimer.ifremer.fr/doc/00042/15296/ | Partager |
![]() | L'exploitation mondiale des crustaces: Bilan et perspectives Auteur(s) : Laubier, A Laubier, Lucien Éditeur(s) : Actes de colloques. Ifremer. Brest [ACTES COLLOQ. IFREMER.]. 1988 Résumé : Since nearly twenty years, world exploitation of crustaceans increases from 1,263,000 tons in 1968 to 3,419,000 tons in 1985, overcoming the predictions of 1970 by more than one million tons. Penaeid prawns fisheries experienced a very fast development. The krill resource proved to be practically commercially unworkable. By now, the major crustaceans stocks appear fully exploited. During the same period, penaeid aquaculture experienced a fast growth, which should continue in the near future. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1987/acte-1407.pdf http://archimer.ifremer.fr/doc/00000/1407/ | Partager |
![]() | Surveillance écologique et halieutique du site électronucléaire de Flamanville. Année 2004 Auteur(s) : Dreves, Luc Le Gac-abernot, Chantal Dagault, Françoise Gaffet, Jean-dominique Lampert, Luis Martin, Jocelyne Schlaich, Ivan Résumé : Monitoring n°22 of the Flamanville nuclear power plant takes into account studies conducted between March and September 2004. Impacts on hydrology, microbiology, phytoplankton, zooplankton, fisheries, intertidal phytobenthos and zoobenthos are reported. This power plant has been in operation for nineteen years. L'étude de surveillance n°22 du site électronucléaire de Flamanville (département de la Manche) concerne l'année 2004. Sont étudiés les domaines benthique, halieutique et pélagique. L'année 2004 est la 19ème année de fonctionnement de la Centrale. Droits : 2005 Ifremer http://archimer.ifremer.fr/doc/2005/rapport-1028.pdf http://archimer.ifremer.fr/doc/00000/1028/ | Partager Voir aussi Pelagos Fisheries Benthos Nuclear power plant Monitoring, Flamanville Pelagos Halieutique Benthos Surveillance Télécharger |
![]() | Fishery externalities and biodiversity: Trade-offs between the viability of shrimp trawling and the conservation of Frigatebirds in French Guiana Auteur(s) : Martinet, Vincent Blanchard, Fabian Éditeur(s) : Elsevier Science Bv Résumé : Sustainable management of natural resources, and in particular fisheries, must take into account several conflicting objectives. This is the case in the French Guiana shrimp fishery for which profitability objectives imply a reduction in the fishing activity. On the one hand, this fishery has negative externalities on marine biodiversity due to discards. On the other hand, this fishery has positive externalities on the economy of the local community and interestingly enough on a protected seabird species in the area (the Frigatebird that feeds on discards). In this paper, we examine the viability of that system considering two sustainability objectives: an economic objective in terms of the profitability of the fishing activity, and a conservation objective in terms of the Frigatebird population. For that purpose, we have developed a dynamic model of that bioeconomic system and study here the trade-offs between the two conflicting objectives. It provides a means to quantify the necessary give and takes involving the economic and ecological objectives that would ensure a viable management solution. Our study confirms the relevance of the viability approach to address natural resource management issues, which should lead to the development of new tools for the arbitration of conflicting sustainability, objectives. In particular, such tools could be used as a quantitative basis for cost-benefit analysis taking into account environmental externalities. (C) 2009 Elsevier B.V. All rights reserved. Ecological Economics (0921-8009) (Elsevier Science Bv), 2009-10 , Vol. 68 , N. 12 , P. 2960-2968 Droits : 2009 Elsevier Ltd All rights reserved. http://archimer.ifremer.fr/doc/00020/13135/10195.pdf DOI:10.1016/j.ecolecon.2009.06.012 http://archimer.ifremer.fr/doc/00020/13135/ | Partager Voir aussi Bio-economic modeling Viability Sustainability Fishery externalities Species conservation Télécharger |
![]() | Surveillance écologique et halieutique du site électronucléaire de Flamanville. Année 2002 Auteur(s) : Dreves, Luc Lampert, Luis Martin, Jocelyne Rumebe, Myriam Schlaich, Ivan Résumé : Monitoring n°20 of the Flamanville nuclear power plant takes into account studies conducted between March and September 2002. Impacts on hydrology, microbiology, phytoplankton, zooplankton, fisheries, intertidal phytobenthos and zoobenthos are reported. This power plant has been in operation for seventeen years. L 'étude de surveillance n°20 du site électronucléaire de Flamanville (département de la Manche) concerne l'année 2002. Sont étudiés les domaines benthique, halieutique et pélagique. L'année 2002 est la 17éme année de fonctionnement de la Centrale. Droits : 2003 Ifremer http://archimer.ifremer.fr/doc/00002/11362/7935.pdf http://archimer.ifremer.fr/doc/00002/11362/ | Partager Voir aussi Centrale nucléaire Flamanville Surveillance Halieutique Pelagos Benthos Flamanville Monitoring Nuclear power plant Benthos Télécharger |
![]() | EU purse seine fishery interaction with marine turtles in the Atlantic and Indian Oceans: a 15 years analyses Auteur(s) : Clermont, Sandra Chavance, Pierre Delgado De Molina, Alicia Murua, Hilario Ruiz, Jon Ciccione, Stephane Bourjea, Jerome Résumé : Bycatch of marine turtles, vulnerable or endangered species, is a growing issue of all fisheries, including Oceanic purse-seine fishery. The present paper seeks to assess marine turtle bycatch at a spatial and temporal level in the European purse seine fishery operating in the Atlantic and Indian Oceans. The study was based on data collected through French and Spanish observer programs from 1995 to 2011, a period where more than 230 000 fishing sets were realized by the UE fleets in both Oceans. A total of 15 913 fishing sets were observed, including 6 515 on drifting Fish Aggregate Devices (FAD) and 9 398 on Free Swimming Schools (FSC). Over the study period, 597 turtles were caught, 86% being released alive at sea. At the same time, from 2003 to 2011, 14 124 specific observations were carried out on floating objects whether they ended in a set or not. 354 marine turtles were observed upon which 80% were already free or entangled alive and therefore released alive. At the temporal and spatial level, data were organized and analysed by Ocean, fishing mode (FAD vs. FSC) as well as by year, quarter and statistical square of 1°. In order to evaluate the impact if this fishery in both Oceans, bycatch distribution was compared to the total fishing effort of the UE fleet, as well as to the known marine turtle post nesting migration routes, nesting population abundances and known feeding areas. The species composition, the size and sex structure of bycatch are also discussed here. At last, an attempt to raise the data to the total fishing effort was carried out. Based on observation of marine turtle by-catches on sets, we estimated that, globally, 3500 marine turtles were accidentally captured by the EU-PS fleet in the Atlantic Ocean from 1995 to 2010, and around 2000 in the Indian Ocean from 2003 to 2010, with a corresponding annual bycatch rate of 218 (SD=150; survival rate =91%) and 250 (SD=157; survival rate =77%) respectively in the Atlantic and Indian Ocean. However, because of important uncertainties mainly due to the low observation coverage and the scarcity of marine turtle bycatch events, it was impossible to produce solid and reliable global estimates of marine turtle bycatch and mortality due to PS activity. Droits : 2012 IOTC http://archimer.ifremer.fr/doc/00149/25991/24087.pdf http://archimer.ifremer.fr/doc/00149/25991/ | Partager |