Do FADs influence the geographical distribution of dolphinfish (Coryphaena hippurus)? Auteur(s) : Taquet, Marc Reynal, Lionel Laurans, Martial Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : For most fisheries, increasing the local production of pelagic fish is the main objective of Fish Aggregating Devices (fads). This does not rule out the existence of a larger-scale impact, especially on the migratory behaviour of fish. The analysis of data collected during 25 experimental fishing surveys around Martinique between 1995 and 1997 has led to the hypothesis that fads influence the migratory behaviour of young dolphinfish. Unlike recent studies of dolphinfish migration in the Caribbean, which tend to show an annual migration pattern with a seasonal passage through the French West Indies, the experimental fishing surveys done over more than a year on a monthly basis on a single cohort, show that the migratory pattern of part of the regional stock could be disrupted. This analysis has made it possible to estimate an average growth rate for this species during the first year of life. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15321/12635.pdf http://archimer.ifremer.fr/doc/00042/15321/ | Partager |
Etude d'une gestion optimale des pecheries de langoustines et de poissons demersaux en mer Celtique Auteur(s) : Laurec, Alain Charuau, Anatole Perodou, Jean-bernard Nedelec, Daniel Biseau, Alain Durand, Jean-louis Rivoalen, Jean-jacques Dupouy, Herve Résumé : The general study, scheduled from 1984 to 1986, aims at providing a judgement about the fisheries in the Celtic Sea. This area has been chosen because it is frequented by EEC vessels with, for the time being, a large majority of French vessels. Activities there are easier to monitor than anywhere else as coastal fisheries are little developed in the area. The final product will consist of a certain number of hypotheses about the planning strategies that could be implemented in the Celtic Sea. The main idea is, firstly, to conduct analytical studies, stock by stock, in order then, to synthesize them into a model integrating the interactions between fleets in relation to their target species. A bio-economical model, deriving from the latter, will enable the simulation of the consequences of the current planning procedures on the management of stocks and vessels. L'étude générale, programmée de 1984 à 1986, vise à fournir un avis sur les pêcheries de Mer Celtique. Cette zone a été choisie car elle est fréquentée par les flottilles de la CEE avec cependant, pour le moment, une dominante française quasi exclusive. Les activités qui s'y exercent peuvent être cernées plus facilement que partout ailleurs car les pêcheries côtières sont très peu développées. Le produit final consistera dans la présentation d'un certain nombre d'hypothèses sur les stratégies d'aménagement adaptables à la Mer Celtique. La voie choisie consiste, dans un premier temps, dans des études analytiques, stock par stock, puis dans leur synthèse dans un modèle intégrant les interactions entre flottilles en relation en particulier avec la recherche des espèces-cibles. Un modèle bio-économique, dérivé du précédent, permettra de simuler les conséquences des procédures habituelles d'aménagement sur la gestion des stocks et des flottilles. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1985/rapport-3671.pdf http://archimer.ifremer.fr/doc/00000/3671/ | Partager Voir aussi monk cuckoo ray blue whiting cod hake ling common dab data bases fishing statistics French fisheries Télécharger |
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 |
Ascidies récoltées par le « Président Théodore Tissier » (campagne de printemps 1951) Auteur(s) : Gravier, R. Éditeur(s) : ISTPM Résumé : From February to June 1951 the "Président-Théodore-Tissier" sailed all the way to the French Caribbean, via Madeira, then to the coasts of Nova Scotia, on the banks of Newfoundland, via the Bermudas, and back to Lorient via the Azores Islands. During this cruise, an important material was sampled by A. Bourdillon, Research Attaché in the Marine Station of Endoume and invited by the Scientific and Technical Institute of Marine Fisheries. Ascidians form the greatest share of this material. They can be grouped in four batches: French Caribbean, Bermudas, Nova Scotia, and Newfoundland. But the French Caribbean batch and that of Newfoundland are by far the most interesting, considering the number and variety of the species they hold. From a geographic point of view, only two groups are worth being studied: 1° The French Caribbean batch which contains only tropical species, to which can be linked the Bermudas batch, islands which although located at a high latitude benefit from a subtropical hydrological regime. 2° The Newfounland batch, which has a cold character, and to which can be linked the Nova Scotia batch. Pendant la période allant du mois de février au mois de juin 1951 le « Président-Théodore-Tissier » a effectué une longue croisière qui, par Madère, l'a mené jusqu'aux Antilles françaises, puis par les Bermudes et les côtes de Nouvelle-Ecosse sur les bans de Terre-Neuve, le cheminl du retour ver Lorient passant par les Açores. Durant cette campagne, un matériel important a été prélevé par A. Bourdillon, attaché de Recherche à la station Marine d'Endoume, invité par l'lnstitut Scientifique et technique des Pêches maritimes pour participer à la croisière. [OCR NON CONTRÔLE] Les ascidies constituent une part importante de ce matériel. Elles peuvent se répartir en quatre lots : Antilles françaies, Bermudes, Nouvelle-Ecosse, Terre-Neuve. Mais le lots de Antilles Française principalement et celui de Terre-Neuve sont de beaucoup les plus intéressants par le nombre et la variété des espèces qu'ils renferment. Du point de vue géographique, deux groupes seulement sont à considérer : 1° Le groupe des Antilles françaises ne renfermant que des espèces de caratères tropical et auquel on peut rattacher le groupe des Bermudes, îles qui malgré leur latitude assez élevée bénéficient d'un régime hydrologique subtropical. 2° Le groupe de Terre-Neuve à caractère froid auquel se rattache le groupe de Nouvelle Ecosse. ATTENTION : Ce texte a été extrait du document par un processus automatique, non contrôlé, de reconnaissance optique de caractères (OCR). Il est donc susceptible de comporter des erreurs. En cas de doute, consultez le fichier PDF. Revue des Travaux de l'Institut des Pêches Maritimes (0035-2276) (ISTPM), 1955-12 , Vol. 19 , N. 4 , P. 612-631 Droits : Ifremer http://archimer.ifremer.fr/doc/1955/publication-6613.pdf http://archimer.ifremer.fr/doc/00000/6613/ | Partager |
Blacktip reef sharks (Carcharhinus melanopterus) show high capacity for wound healing and recovery following injury Auteur(s) : Chin, Andrew Mourier, Johann Rummer, Jodie L Auteurs secondaires : Centre for Sustainable Tropical Fisheries and Aquaculture ; James Cook University (JCU) Laboratoire d'Excellence CORAIL (LabEX CORAIL) ; Institut de Recherche pour le Développement (IRD) - Université des Antilles et de la Guyane (UAG) - École des hautes études en sciences sociales (EHESS) - École pratique des hautes études (EPHE) - Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) - Université de la Réunion (UR) - Université de la Polynésie Française (UPF) - Université de Nouvelle Calédonie - Institut d'écologie et environnement Centre de recherches insulaires et observatoire de l'environnement (CRIOBE) ; Université de Perpignan Via Domitia (UPVD) - École pratique des hautes études (EPHE) - Centre National de la Recherche Scientifique (CNRS) ARC Centre of Excellence for Coral Reef Studies (CoralCoE) ; James Cook University (JCU) Éditeur(s) : HAL CCSD Résumé : International audience Wound healing is important for sharks from the earliest life stages, for example, as the 'umbilical scar' in viviparous species heals, and throughout adulthood, when sharks can incur a range of external injuries from natural and anthropogenic sources. Despite anecdotal accounts of rapid healing in elasmobranchs, data regarding recovery and survival of individuals from different wound or injury types has not been systematically collected. The present study documented: (i) 'umbilical scar' healing in wild-caught, neonatal blacktip reef sharks while being reared for 30 days in flow-through laboratory aquaria in French Polynesia; (ii) survival and recovery of free-swimming blacktip reef sharks in Australia and French Polynesia following a range of injuries; and (iii) long-term survival following suspected shark-finning activities. Laboratory monitoring, tag-recapture records, telemetry data and photo-identification records suggest that blacktip reef sharks have a high capacity to survive and recover from small or even large and severe wounds. Healing rates, recovery and survival are important factors to consider when assessing impacts of habitat degradation and fishing stress on shark populations. The present study suggests that individual survival may depend more on handling practices and physiological stress rather than the extent of physical injury. These observations also contribute to discussions regarding the ethics of tagging practices used in elasmobranch research and provide baseline healing rates that may increase the accuracy in estimating reproductive timing inferred from mating scars and birth dates for neonatal sharks based on umbilical scar healing status. Cite as: Chin A, Mourier J, Rummer JL (2015) Blacktip reef sharks (Carcharhinus melanopterus) show high capacity for wound healing and recovery following injury. Conserv Physiol 3: doi:10.1093/conphys/cov062. Conservation physiology Droits : http://creativecommons.org/licenses/by/ hal-01250745 https://hal-univ-perp.archives-ouvertes.fr/hal-01250745 https://hal-univ-perp.archives-ouvertes.fr/hal-01250745/document https://hal-univ-perp.archives-ouvertes.fr/hal-01250745/file/Conserv%20Physiol-2015-Chin-.pdf DOI : 10.1093/conphys/cov062 | Partager |
Fish aggregating devices (FADs): good or bad fishing tools? A question of scale and knowledge FOREWORD: Tahiti International Conference "Tuna Fisheries and FADs", November 2011 Auteur(s) : Taquet, Marc Éditeur(s) : Edp Sciences S A Résumé : It is estimated that fish aggregating devices (FADs) are now used for over 40% of world tropical tuna catches, making this technique a major phenomenon for high seas fisheries worldwide, and one that has experienced great expansion over the past three decades. The question of whether the FAD is a good or a bad tool for the exploitation of marine resources depends on many parameters. To respond to this question, it is necessary to distinguish different scales of exploitation (artisanal vs. industrial) and various types of FADs (anchored vs. drifting), but it is also very important to gather more data and conduct further research on this topic to gain a better understanding of the phenomenon and of its impacts. As such, twelve years after the first international conference devoted to FADs, which was held in Martinique (French West Indies), a new multi-scalar global assessment of FAD fisheries development and a review of the progress of research in this field was deemed vital. The latest international conference, "Tuna Fisheries and Fish Aggregating Devices", was held in Tahiti in November 2011, and it was an event that welcomed nearly 150 conference attendees from 40 different countries, three ocean regions, and the Mediterranean. This is an analysis of the relevant literature gathered by the author in the bibliographic database FADBASE. Then, the major issues already addressed by the scientific community are set out, and gaps and research priorities are highlighted for anchored and drifting FADs management. Aquatic Living Resources (0990-7440) (Edp Sciences S A), 2013-01 , Vol. 26 , N. 1 , P. 25-35 Droits : EDP Sciences, IFREMER, IRD 2013 http://archimer.ifremer.fr/doc/00137/24835/22915.pdf DOI:10.1051/alr/2013043 http://archimer.ifremer.fr/doc/00137/24835/ | Partager |
Les cantonnements de pêche à la Martinique : bilan et perspectives Auteur(s) : Valdivia, Florence Éditeur(s) : Université des Antilles Études caribéennes Résumé : Le cantonnement de pêche est un outil administratif et juridique français employé pour la gestion de la ressource halieutique et la réglementation de la pêche sur un site marin défini. Cet outil a été mis en place à la Martinique (Petites Antilles) en 1999, à la demande des marins-pêcheurs confrontés à la raréfaction des stocks de poissons au sein de la bande côtière. Les autorités compétentes sur le milieu marin ont installé ce dispositif sur huit zones réparties autour de l’île (de la côte Atlantique à la côte Caraïbes). Le cantonnement de pêche reste peu documenté scientifiquement à ce jour, en dehors d’inventaires ichtyologiques réalisés par des scientifiques-biologistes. Il est donc opportun de retracer les étapes de la mise en place de cet outil et d’analyser les premiers résultats et les enjeux. Cantonment fishing is a French legal and administrative tool used to manage fisheries resources and the regulation of fishing on marine site defined. This tool was developed in Martinique (Lesser Antilles) in 1999, at the request of fishermen facing depletion of fish stocks in the coastal strip. The competent authorities on the marine environment have installed this device on eight areas spread around the island (the Atlantic coast to the Caribbean coast). Cantonment fishing is little scientifically documented to date, apart from fishery surveys conducted by scientists-biologists. It is therefore appropriate to retrace the steps of the development of this tool and analyze the first results and challenges. Martinique Droits : info:eu-repo/semantics/openAccess urn:doi:10.4000/etudescaribeennes.6800 http://journals.openedition.org/etudescaribeennes/6800 | Partager |
Estimating tropical tree diversity indices from forestry surveys: a method to integrate taxonomic uncertainty Auteur(s) : Guitet, Stéphane Sabatier, Daniel Brunaux, Olivier Herault, Bruno Aubry-Kientz, Melaine Molino, Jean-François Baraloto, Christopher Auteurs secondaires : Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (CIRAD) - Institut national de la recherche agronomique [Montpellier] (INRA Montpellier) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS) - Institut de Recherche pour le Développement (IRD [France-Sud]) Office National des Forêts (ONF) 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 Elsevier Résumé : Analyses of tree diversity and community composition in tropical rain forests are usually based either on general herbarium data or on a restricted number of botanical plots. Despite their high taxonomic accuracy, both types of data are difficult to extrapolate to landscape scales. Meanwhile, forestry surveys provide quantitative occurrence data on large areas, and are thus increasingly used for landscape-scale analyses of tree diversity. However, the reliability of these approaches has been challenged because of the ambiguity of the common (vernacular) names used by foresters and the complexity of tree taxonomy in those hyper-diverse communities.We developed and tested a novel approach to evaluate taxonomic reliability of forestry surveys and to propagate the resulting uncertainty in the estimates of several diversity indicators (alpha and beta entropy, Fisher-alpha and Sørensen similarity). Our approach is based on Monte-Carlo processes that simulate communities by taking into account the expected accuracy and reliability of common names. We tested this method in French Guiana, on 9 one-hectare plots (4279 trees – DBH ⩾ 10 cm) for which both common names and standardized taxonomic determinations were available. We then applied our method of community simulation on large forestry inventories (560 ha) at the landscape scale and compared the diversity indices obtained for 10 sites with those computed from precise botanical determination situated at the same localities.We found that taxonomic reliability of forestry inventories varied from 22% (species level) to 83% (family level) in this Amazonian region. Indices computed directly with raw forestry data resulted in incorrect values, except for Gini–Simpson beta-diversity. On the contrary, our correction method provides more accurate diversity estimates, highly correlated with botanical measurements, for almost all diversity indices at both regional and local scales. We obtained a robust ranking of sites consistent with those shown by botanical inventories.These results show that (i) forestry inventories represent a significant part of taxonomic information, (ii) the relative diversity of regional sites can be successfully ranked using forestry inventory data using our method and (iii) forestry inventories can valuably contribute to the detection of large-scale diversity patterns when biases are well-controlled and corrected.The tools we developed as R-functions are available in supplementary material and can be adapted with local parameters to be used for forest management and conservation issues in other regional contexts ISSN: 0378-1127 hal-01204219 https://hal.archives-ouvertes.fr/hal-01204219 DOI : 10.1016/j.foreco.2014.05.045 PRODINRA : 286554 | Partager |
Analyzing the market position of fish species subject to the impact of long-term changes: a case study of French fisheries in the Bay of Biscay Auteur(s) : Le Floc' H, P Poulard, Jean-charles Thebaud, Olivier Blanchard, Fabian Bihel, J Steinmetz, Fabien Éditeur(s) : EDP Sciences Résumé : Market position and its evolution were analysed in nine key fish and cephalopod species subject to long-term changes, using the Bay of Biscay fisheries as a case study. Although such long term changes have already been documented, and in some cases shown to be related to the impacts of fishing, changes in the physical environment, or both, relatively little work has been devoted to their potential consequences in economic terms. The nature and extent of these consequences was determined in the present study by looking at the composition of the affected fish production, and the status of different fish products on the markets. We propose a methodology to characterize market position for this set of nine species. The selected species represent a significant part of the gross turnover of French fishing fleets operating in the bay. These species were characterized in terms of their potential sensitivity to fishing and changes in environmental conditions due to global warming. We separated species potentially positively (Engraulis encrasicolus and Lophius budegassa) and negatively affected (Pollachius pollachius and Lophius piscatorius) by warming. Evolution of the value of production of the nine species was then depicted using analysis of macro-economic index (production and potential consumption) and price indices. This revealed the relatively high sensitivity of domestic production to the market crisis that occurred in France in the early 1990s, compared to imported and exported products. The relative position of individual species, with respect to the market and its evolution between 1990 and 2005, was analyzed by multi-factorial analysis. Results derived from the analysis clearly distinguish two groups of species, the first characterized by higher prices (monkfish, Nephrops, sole, seabass) and the second by larger volumes available on the French market (pollack, hake, anchovy, sardine, cuttlefish). We conclude that a major part (69 to 87%) of the gross turnover associated with catches of these fish species in the Bay of Biscay remains potentially unaffected by long-term changes related to climate. Aquatic Living Resources (0990-7440) (EDP Sciences), 2008-07 , Vol. 21 , N. 3 , P. 307-316 Droits : EDP Sciences, IFREMER, IRD 2008 http://archimer.ifremer.fr/doc/2008/publication-4716.pdf DOI:10.1051/alr:2008047 http://archimer.ifremer.fr/doc/00000/4716/ | Partager |
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 |
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 |
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 |
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 |
Évolution de l'écosystème pélagique du Golfe de Gascogne pendant la période 1990-2003. Conséquences sur la capturabilité des espèces Auteur(s) : Villalobos, Hector Éditeur(s) : Université de Bretagne Occidentale Résumé : Several small pelagic fish species contribute remarkably to world catch. Their populations are, however, characterized by large biomass fluctuations strongly affecting fisheries. The fishing gears and methods used to capture small pelagics have evolved to exploit the highly developed shoaling behavior of these species. Hence, faced to modern fishing this gregarious behavior becomes a disadvantage for fish. Fish behavior may be affected by environmental conditions and by fishing, at the same time that behavior impacts fishing. In this study, we seek to characterize the aggregative systems of small pelagic fishes inhabiting the Bay of Biscay by analyzing "acoustic images", defined as the group of echoes (planktonic layers, shoals, isolated targets) detected on a transect section of a given length. We analyzed the species composition, the spatial distribution and the evolution over time of acoustic images. We also studied the hydrological conditions of the bay, as well as the small pelagics French fishery in order to look for correlations between hydrology, commercial catch and fish aggregation patterns observed by acoustics. We observed the same species or group of species forming different types of aggregation according to habitat. Conversely, the same type of aggregation, associated with a particular habitat, can be produced by different species. The most notorious change observed during the studied period relates to small clupeoids aggregations in the vicinity of the Gironde estuary, whose structure evolved toward a greater fragmentation of shoals (a large number of small size detections) since 2000. Concerning commercial catches, pelagic trawlers fishing in pairs mainly seek for anchovy in the coastal areas, single pelagic trawlers capture mackerel and horse mackerel in deeper waters while purse seiners target mostly sardine near their fishing ports. Because of the coarse spatial resolution of commercial fishing data and the effect of the application of an international fisheries agreement limiting the fishing activity of French pelagic trawlers during spring, only small correlations between captures and types of aggregation were observed. La participation des petits poissons pélagiques dans les captures est remarquable. Leurs populations sont cependant caractérisées par des importantes fluctuations de biomasse, impactant fortement les pêcheries. Les méthodes et appareils de pêche utilisés pour capturer ces espèces ont évolué dans le sens d'exploiter le comportement grégaire très développé des petits pélagiques. Cette tendance à former de bancs devient alors désavantageuse pour le poisson face à la pêche moderne. Les conditions environnementales et la pêche peuvent affecter le comportement du poisson, en même temps que ce dernier est susceptible d'affecter l'activité halieutique. Le but de cette étude est de caractériser les systèmes agrégatifs des petits poissons pélagiques dans le golfe de Gascogne en étudiant des « images acoustiques », définies comme l'ensemble des échos (couches planctoniques, bancs, cibles isolées) détectés sur une section de radiale de longueur donnée. Nous analysons leur composition en espèces ainsi que leur distribution spatiale et leur évolution au cours du temps. Nous étudions aussi les conditions hydrologiques du golfe, ainsi que la pêcherie française de ces espèces afin de chercher des corrélations entre l'hydrologie, la capture commerciale et les types d'agrégations observés par acoustique. Nous avons observé qu'une espèce est capable de former des agrégations différentes en fonction de l'habitat, et inversement, le même type d'agrégation, associé à un habitat particulier, peut être produit par des espèces différentes. Le changement observé le plus évident concerne les agrégations de petits clupéiformes, dont la structure a évolué vers une plus grande fragmentation des détections (des petits bancs plus nombreux) depuis 2000. Par rapport à la pêche des professionnels, les chalutiers pélagiques en boeufs recherchent en priorité l'anchois dans la zone côtière, les pélagiques simples capturent le chinchard et le maquereau au large et les senneurs recherchent principalement la sardine à proximité des ports de pêche. À cause de la résolution spatiale trop sommaire des données de pêche et l'effet de l'application des accords internationaux limitant l'activité des chalutiers pélagiques au printemps, nous n'avons observé que peu des corrélations entre les captures et les types d'agrégation établis à partir de données issues des campagnes scientifiques. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/2008/these-6083.pdf http://archimer.ifremer.fr/doc/00000/6083/ | Partager |
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 |
Red-drum (Sciaenops ocellata) farming in Martinique: a new prospect for Caribbean marine aquaculture ? Auteur(s) : Paquotte, Philippe Éditeur(s) : Communication at the IIFET Conference Tromso 1998 Résumé : (not controled OCR) like most other caribbean islands, martinique suffers a reduction in fisheries resources and is now a net importer of seafood products since no major expansion of aquaculture production has been done. nevertheless, this island has numerous assets for marine aquaculture development : tropical clean waters, developed infrastructures and market channels, financial support for research, training and extension due to its tight political and economic connection with france. red drum is a subtropical fish introduced in martinique in 1985 from the south of usa for aquaculture purposes. from 1987 to 1993, ifremer worked on rearing techniques in martiniquan conditions. once the farming techniques were perfected, questions raised about red drum marketing potential and of economic viability of red drum farms in order to attract investments and entrepreneurs. that is the reason why a market analysis and a financial analysis have been carried out. the results of these studies indicate that martiniquan fish farming could be profitable, due to the rapid build-up of the facilities and to the sho rt production cycles. the good quality of infrastructures in martinique, the high purchase power of the population in comparison with most caribbean islands and the frequent air links with europe are important comparative advantages. the market analysis has revealed a good potential on the domestic market thanks to the development of the supermarkets, but has underlined the price constraint. for the french market too, production costs have to be lowered in order to compete on a market dominated by salmon. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1998/acte-2546.pdf http://archimer.ifremer.fr/doc/00000/2546/ | Partager |
Technologie et utilisation des DCP ancres dans les eaux de la collectivite territoriale de Mayotte (archipel des Comores, canal du Mozambique, ocean Indien) Auteur(s) : Wendling, Bertrand Le Calve, S Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : The volcanic island of Mayotte (374 km super(2)) is part of the Comoros Archipelago, which is situated on the North of Mozambic's Canal (Indian Ocean). Mayotte is composed of two islands and some thirty small islands distributed in a lagoon of more than 1,000 km super(2). Being one of the French Republic's Territorial Collectivity, this island is characterized by a very fast demographic evolution (growth rate : 5.8 %), which constitutes the foundation of the development problematic. Most of local halieutic production comes from the reef (nearly 2,000 t in 1999), the technic of "palangrotte" (deep line) is still dominating. The fishing fleet is composed of monoxyl pirogues and polyester fishing boats for the 1,200 fishermen. The first FADs (Fish Aggregating Devices) were installed in 1989. Now, 5 FADs are situated in the lagoon whereas 10 others have been installed out of it. If it is very hard to evaluate economic impact of FAD in Mayotte, their success seems to be limited because of several local constraints : fear to fish out of the lagoon, little interest in tuna, lack of formation. Nevertheless, faced to the demographic evolution and the decrease of the reef ressources, a program of fishing development on FAD has been initiated in 1998, with those following themes : realization of a new prototype of FAD, experimental fishing program with vertical drift "long line", teaching programs for the local fishermen. Today, it is too early to analyze the informations already collected, but the results are very promising, and validate the technical improvement of the new prototype.Original Abstract: L'ile volcanique de Mayotte (374 km super(2)) fait partie de l'archipel des Comores situe au Nord du canal du Mozambique (ocean Indien). Mayotte comprend deux iles et une trentaine d'ilots repartis dans un lagon de plus de 1 000 km super(2). Collectivite territoriale de la Republique francaise, l'ile se caracterise par une evolution demographique tres rapide (taux de croissance: 5,8 %), qui constitue le socle de toutes les problematiques de developpement. L'essentiel de la production halieutique provient du milieu recifal (environ 2 000 t en 1999), la peche a la ligne de fond reste la technique dominante. La flottille de peche est constituee de pirogues monoxyles et de barques polyester pour une population de 1 200 pecheurs. Les premiers DCP mahorais furent installes en 1989. A ce jour, on denombre cinq DCP dans le lagon et dix hors lagon. Il semble que leur succes soit reste limite en raison de plusieurs contraintes locales : peur de la peche hors lagon, peu d'interet pour les poissons pelagiques, manque de formation. Neanmoins, face a l'explosion demographique et a l'appauvrissement des ressources lagonaires, un nouveau programme de developpement de la peche sur DCP a ete initie en 1998. Ce programme comporte trois axes : realisation d'un nouveau prototype de DCP, lancement d'un programme de peches experimentales a la palangre verticale derivante et formation des pecheurs. A ce jour, les informations obtenues sont trop parcellaires pour etre analysees mais les donnees et observations realisees sur les nouveaux dispositifs permettent de valider leur conception technique. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15290/12647.pdf http://archimer.ifremer.fr/doc/00042/15290/ | Partager |
Evolution des captures de poissons démersaux profonds, au vire-ligne électrique, dans l'ouest de la Réunion, entre 2000 et 2011 Auteur(s) : Fleury, Pierre-gildas Aureche, Vincent Le Ru, Loic Résumé : In the aim of diversification for small fisheries, a survey has been conducted in 2000 by the Regional Fisheries Committee and the French Institute for Exploitation of the Sea (Ifremer) between 200 and 600 m deep, in the West of Reunion Island. Potential commercial fish stocks have been found out. Numerous professional and recreational fishermen have bought equipment in order to exploit this resource (electric winches). But deep demersal fish is a fragile resource due mainly to low growth and late sexual maturation. Face to this increasing pressure upon a fragile resource, a new survey has been carried out by Ifremer in 2011, with use of the same fishing sites, material and method than in 2000. Results displayed in this report are compared to those of 2000. It turned out that yields of commercial species have decreased in an alarming way (over 90%) together with the fish sizes, data which exhibit a stock overfishing. The only catches of the non commercial species (small squale "Zépine" Squalus megalops) appear comparable to 2000. This survey has now to be confirmed all around Reunion Island. Dans la perspective de diversifier la petite pêche réunionnaise, une campagne de prospection a été réalisée en 2000 par le Comité Régional des Pêches Maritimes (CRPM) et l'Institut Français de Recherche pour L'Exploitation de la Mer (Ifremer) sur des fonds de 200 à 600 m, dans l'ouest de l'île de La Réunion. Elle a montré l'existence de stocks commercialement intéressants. De nombreux pêcheurs, professionnels et plaisanciers se sont équipés en moulinets électriques pour exploiter ces ressources. Cependant les poissons démersaux profonds représentent une ressource fragile du fait, notamment, de leur croissance lente et de leur reproduction tardive. Face à cette augmentation de la pression de pêche sur une ressource fragile, une nouvelle campagne expérimentale a été menée en 2011 par l'Ifremer, en utilisant les mêmes sites de pêche, le même matériel et la même méthodologie qu’en 2000. Les résultats présentés dans ce rapport sont comparés avec ceux de la campagne de 2000. Il s’avère que les rendements en espèces commerciales ont diminué de façon très nette (plus de 90%) ainsi que la taille des poissons capturés, données caractéristiques d'une surexploitation des stocks. Seules les captures de requins zépines (Squalus megalops) non commercialisées à La Réunion restent comparables à celles de 2000. Il convient maintenant de valider ces résultats tout autour de l'île de La Réunion. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00050/16100/13643.pdf http://archimer.ifremer.fr/doc/00050/16100/ | Partager |
Analyse socio-économique de l'exploitation des crevettes en Guyane française Auteur(s) : Gilly, Bernard Cochet, Y Résumé : Shrimp fisheries in French Guyana suffer from the influence of exogenous pressures on shrimp stock. In terms of shrimp stock, the fluctuations in recruitment are very high and determine for the most part the annual production of shrimp boats (Figure 1). Work in progress on the evolution of shrimp stocks suggest that the relatively short shrimp life span (18 months) does not allow a cohort to be exploited over more than one year. In terms of the shrimp boat fleet, there are no alternative outlets for fishing effort. La pêcherie crevettière de Guyane française se trouve à.. cet égard dans des conditions extrêmes. Au plan de la ressource, les fluctuations du recrutement sont très importantes et déterminent en grande partie les résultats annuels des flottilles (figure 1). Les travaux en cours relatifs à la dynamique des stocks de crevettes permettent de considérer que la durée de vie relativement brève des crevettes (18 mois) ne permet pas à un recrutement d'être exploité sur plus d'une année. Au plan des flottilles, il n'existe à. l'heure actuelle aucune possibilité alternative d'allocation de l'effort de pêche. [OCR NON CONTRÔLE] Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/1987/rapport-4138.pdf http://archimer.ifremer.fr/doc/00000/4138/ | Partager |
Effets du plan de protection des thonides de l'Atlantique 1998-1999 d'apres les observations faites sur les thoniers senneurs geres par les armements francais Auteur(s) : Goujon, Michel Labaisse-bodilis, C Éditeur(s) : Pêche thonière et dispositifs de concentration de poissons, Caribbean-Martinique, 15-19 Oct 1999 Résumé : In 1998, the French and Spanish tuna-boat owners associations have volentarily reconducted the Atlantic tuna protection plan (also called moratorium) initiated the previous year. This plan which has become an iccat recommendation for 1999, consists mainly in preventing fishing on floating objects (logs) and in having observers on board tuna purse seiners. Data collected by these observers and landing statistics allow to draw preliminary conclusions on some effects of the protection plan, on the fleets and on the Atlantic tuna stocks. Largely respected, the moratorium has led to a spatial redistribution of the fishing effort, an important reduction of the proportion of sets on logs and a decrease of the landings by one third compared to those realised the years before during the same months, particularily for the skipjack and the bigeye tunas. Moreover, data collected allow to calculate catch rates for a number of by-catch species in the purse seine fishery. Droits : info:eu-repo/semantics/openAccess http://archimer.ifremer.fr/doc/00042/15313/12660.pdf http://archimer.ifremer.fr/doc/00042/15313/ | Partager |