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| Registros recuperados: 50 | |
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| Taquet, Marc; Gaertner, Jean-claude; Bertrand, Jacques. |
| This work aims to define a typology of trawler f1eet in Sète, the main fishing harbour along the French Mediterranean coast, using several multivariate analysis methods. The fishing ships taken to account are represented by annual profiles of landing specific compositions. Five fishing strategies have been identified. A segmentation method using symbolic objects allows a formaI characterisation of the different strategies. These strategies are studied according to several general characteristics usually used for management rules elaboration (power, length, ship age). The typological analysis allows to characterise two main exploitation ways, one directed to the catch of a few species (Engraulis encrasicolus, Sardina pilchardus), the other characterised by... |
| Tipo: Text |
Palavras-chave: Flotille; Stratégie; Chalutage; Analyse multivariée; Méditerranée; Fleet; Strategy; Fish trawling; Multivariate analysis; Mediterranean sea. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00113/22404/20101.pdf |
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| Bertrand, Jacques. |
| La pêche des crustacés aux casiers constitue une part très importante de l'activité des navires (du doris au petit chalutier ponté) travaillant entre la pointe du Rozel et le cap de La Hague. Elle est pratiquée sur une période s'étendant de mars à octobre, les limites variant sensiblement suivant les années. Les activités de quatre des dix bateaux travaillant dans le secteur ont été suivies régulièrement par le relevé de carnets de pêche remplis quotidiennement par les pêcheurs. Ces quatres unités constituent un échantillonnage assez large de la flottille : du doris (environ 60 casiers) au petit chalutier (environ 400 casiers) en passant par le picoteux (environ 150 casiers) ; de ce fait on présente les différentes techniques de travail utilisées. La... |
| Tipo: Text |
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| Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/00046/15719/13121.pdf |
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| Bertrand, Jacques; Chevalier, Robert. |
| One of the primary uses of trawl survey data is the estimation of abundance of the species involved. But these direct estimates give results with generally a high variability. Reducing this latter is one of the main problems for the scientists involved in such a research. Methods to achieve a better efficiency have been implemented. Nevertheless estimations remain highly variable, so the information on the changes in population, enclosed in the observed series of survey indices is mixed with a noise component result of both the survey sampling variability and effect of uncontrolled factors. PENNING'roN ( 1985) proposed time series models to filter measurement error from the signal. However the length of the series does not always allow using time series... |
| Tipo: Text |
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| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00388/49925/50499.pdf |
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| Bertrand, Jacques. |
| L'analyse des résultats de l'activité de pêche au cours des trois dernières décennies ilustre les prospections engagées et les efforts développés tant dans le domaine de la petite pêche que dans ceux de la pêche côtière et de la pêche au large ou de la grande pêche industrielle pour maintenir ou accroitre la production de ce secteur d'activité. |
| Tipo: Text |
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| Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/00388/49922/50495.pdf |
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| Rochet, Marie-joelle; Trenkel, Verena; Carpentier, Andre; Coppin, Franck; Gil De Sola, Luis; Leaute, Jean-pierre; Mahe, Jean-claude; Maiorano, Porzia; Mannini, Alessandro; Murenu, Matteo; Piet, Gerjan; Politou, Chrissi-yianna; Reale, Bruno; Spedicato, Maria-teresa; Tserpes, George; Bertrand, Jacques. |
| P>1. The development of ecosystem approaches to environmental management implies the need to account for multiple pressures on ecosystems. Trends in multiple metrics that respond differently to changes in major environmental pressures need to be combined to evaluate the impacts of fishing and environmental changes on fish communities. 2. An exploited fish community is viewed as a three-level food chain in which the two upper levels, or functional groups, are targeted by fishing fleets, while the lowest level is subject to environmental variation. Qualitative modelling is used to predict changes at the two upper levels, that is, top-down vs. bottom-up perturbations. Abundance and length metrics are calculated from survey data for 14 Mediterranean and... |
| Tipo: Text |
Palavras-chave: Bottom-up control; Community metrics; Compensation; Ecosystem approach to fisheries; Ecosystem assessment; Functional groups; Groundfish community; Mediterranean; North Atlantic; Top-down control. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00008/11925/8637.pdf |
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| Bertrand, Jacques; Souplet, Arnauld; Gil De Sola, Luis; Relini, Giulio; Politou, Chrissi-yianna. |
| This document is the fifth version of a manual elaborated in the frame of an international project to harmonise the samplings by bottom trawling of the demersal resources in the Mediterranean Sea (MEDITS program). It is the reference document for the surveys to be conducted from 2007 onwards by the research institutes contributing in the Medits surveys on the continental shelves and slopes in the Mediterranean (Fig. 1). The manual describes the sampling gear characteristics, the sampling methodology and the treatment of the samples. Finally it gives the specifications of the data files for data storage and exchange. |
| Tipo: Text |
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| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/00002/11321/7850.pdf |
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| Bertrand, Jacques. |
| Avec le doublement de l'effectif des chalutiers entre 1984 et 1987, la flottille des navires de pêche industrielle de Saint-Pierre et Miquelon est actuellement composée de six unités, cinq chalutiers de pêche fraîche et un congélateur. Les analyses conduites sur les données de 1986 ont montré que cette flottille était très homogène tant en référence aux caractéristiques techniques et à la pui ssance de pêche des navires qu'en terme de stratégie d'exploitation (zones de pêche, espèces recherchées). Après une diminution jusqu'à 4500 tonnes au début des années soixante-dix, les captures de la flottille industrielle de Saint-Pierre et Miquelon ont augmenté régulièrement jusqu'à atteindre 23 000 tonnes en 1986 et en 1987. Cette évolution est marquée par... |
| Tipo: Text |
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| Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/1988/rapport-3940.pdf |
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| Bertrand, Jacques; Cochard, Marie-laure; Coppin, Franck; Le Pape, Olivier; Mahe, Jean-claude; Morin, Jocelyne; Poulard, Jean-charles; Rochet, Marie-joelle; Schlaich, Ivan; Souplet, Arnauld; Trenkel, Verena; Verin, Yves. |
| The scientist community, the fishing organisations and all involved parties show a growing interest in an integrated project management of the sea space exploited by fishing communities. A key to reach such a target is to make available reliable and precise scientist data on the different components of the fishing systems. For about twenty years, and in its mission to support the development of an integrated management for a sustainable use of marine resources, Ifremer has been organising monitoring campaigns of fishery resources along the shores of France. These campaigns aim at providing abundance indicator on species of interest. They consequently provide an essential knowledge base to characterize and trace the status of exploited fish and... |
| Tipo: Text |
Palavras-chave: Ecosystem; Indicating; Oceanographical campaign; Scientific research; Fishing halieutic; Fishing; English Channel; Bay of Biscay; France; Invertebrate; Pisces; Ecosystème; Indicateur; Campagne océanographique; Recherche scientifique; Pêche halieutique; Pêche; Mer du nord; Golfe de gascogne; Manche; France; Invertebrate; Pisces. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/rapport-1091.pdf |
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| Registros recuperados: 50 | |
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