102 research outputs found
Pleuronectes platessa, una especie fantasma en el Mediterráneo?
European plaice Pleuronectes platessa often appears in ichthyological check lists for the Mediterranean Sea, as well as in regional field guides and even in some official national landings statistics. However we have not found a single ichthyologist or fisheries biologist who has actually observed this fish in the Mediterranean. The ichthyologic sources available, from classical antiquity to recent times, were checked in order to follow the track of the citations (i.e. true field observations or citations of former authors), and to try to detect misidentifications, if any. Few of these citations appear to be reliable and misidentifications with flounder Platichthys flesus are frequent. Recent scientific trawl surveys have not reported any observations of plaice. The statistics provided by France to the FAO with positive catches of P. platessa appear to be misidentifications of P. flesus. Plaice may have been present in some areas of the Mediterranean in the past, as a result of climatic changes related to the ice age. However, the species seems to be absent now. We propose that this species should be removed from the ichthyofauna records of the Mediterranean.La especie Pleuronectes platessa aparece a menudo en los listados de peces del Mediterráneo, guías de identificación de especies mediterráneas, e incluso en estadísticas oficiales. Sin embargo no hemos encontrado un solo ictiólogo o biólogo pesquero que la haya observado en dicho mar. Se han comprobado las obras de ictiología desde la antiguedad clásica hasta nuestros días con el fin de seguir la pista de las citas, por si son auténticas observaciones de campo o citas de autores anteriores, y tratar de detectar errores de identificación en caso que los haya. Pocas citas aparecen como verdaderamente confiables, la mayoría no lo son. Las confusiones con Platichthys flesus son frecuentes. Las campañas científicas recientes tampoco han proporcionado ninguna observación de Pleuronectes platessa. Las estadísticas que Francia ha proporcionado a la FAO con capturas de esta especie, resultan ser confusiones de identificación con Platichthys flesus. Pleuronectes platesa podría haber estado presente en algunas áreas del Mediterráneo en el pasado como resultado de los cambios climáticos relacionados con la pequeña edad del hielo. No obstante parece que en la actualidad es ausente. Proponemos eliminar la especie de los registros de la fauna ictiológica del Mediterráneo
Demandas sociales / dispositivos grupales / comunitarios
Nos proponemos reflexionar acerca de las múltiples demandas sociales que convergen en el campo de la salud mental comunitaria, pensando estas cuestiones desde una perspectiva que privilegia los acontecimientos que promueven los abordajes grupales.Mesas temáticas autoconvocadas: Formación en psicología y demandas socialesFacultad de Psicologí
Demandas sociales / dispositivos grupales / comunitarios
Nos proponemos reflexionar acerca de las múltiples demandas sociales que convergen en el campo de la salud mental comunitaria, pensando estas cuestiones desde una perspectiva que privilegia los acontecimientos que promueven los abordajes grupales.Mesas temáticas autoconvocadas: Formación en psicología y demandas socialesFacultad de Psicologí
Demandas sociales / dispositivos grupales / comunitarios
Nos proponemos reflexionar acerca de las múltiples demandas sociales que convergen en el campo de la salud mental comunitaria, pensando estas cuestiones desde una perspectiva que privilegia los acontecimientos que promueven los abordajes grupales.Mesas temáticas autoconvocadas: Formación en psicología y demandas socialesFacultad de Psicologí
Potentialités du radar SAR en halieutique : application à la pêche thonière de surface et à la pêche artisanale
... L'expérimentation HAREM (Halieutique et Radar : Expérimentation en Méditerranée), en prélude à un véritable programme, a évalué, pour la première fois, les potentialités, la qualité et l'originalité des données acquises en mer par ce type de radar en matière de biologie des pêches et d'environnement halieutique. HAREM a été menée en août 1989, avec le radar allemand E-SAR du DLR monté sur un avion Dornier 228. La difficulté principale a été d'estimer le créneau météorologique d'abord, puis halieutique, favorable sur quelques jours, de façon à disposer simultanément et en un même lieu des pêcheurs, des bancs de thons et des acquisitions radar. Dès les premiers vols, nous avons pu vérifier notre hypothèse : bancs de thons, cétacés, ainsi qu'engins de pêche, (bateaux, filets, pièges à poissons) sont détectables et identifiables avec un radar SAR (bande C, polarisation VV) par l'intermédiaire du signal généré par la déformation de la surface de l'eau. L'objectif de HAREM a été ainsi complètement atteint. A partir des données recueillies, des simulations de type ERS-1, par dégradation géométrique des données, ont été effectuées et semblent prometteuses en ce qui concerne la pêche thonièr
Marine strategy framework directive task group 3 Report commercially exploited fish and shellfish
Marine Strategy Framework Directive - Task Group 3 Report - Commercially exploited fish and shellfish
The Marine Strategy Framework Directive (2008/56/EC) (MSFD) requires that the European
Commission (by 15 July 2010) should lay down criteria and methodological standards to allow
consistency in approach in evaluating the extent to which Good Environmental Status (GES) is being
achieved. ICES and JRC were contracted to provide scientific support for the Commission in meeting
this obligation.
A total of 10 reports have been prepared relating to the descriptors of GES listed in Annex I of the
Directive. Eight reports have been prepared by groups of independent experts coordinated by JRC
and ICES in response to this contract. In addition, reports for two descriptors (Contaminants in fish
and other seafood and Marine Litter) were written by expert groups coordinated by DG SANCO and
IFREMER respectively.
A Task Group was established for each of the qualitative Descriptors. Each Task Group consisted of
selected experts providing experience related to the four marine regions (the Baltic Sea, the Northeast
Atlantic, the Mediterranean Sea and the Black Sea) and an appropriate scope of relevant
scientific expertise. Observers from the Regional Seas Conventions were also invited to each Task
Group to help ensure the inclusion of relevant work by those Conventions. This is the report of Task
Group 3 Commercially exploited fish and shellfish.JRC.DG.G.4-Maritime affair
Silver eel population size and escapement in a Mediterranean lagoon: Bages-Sigean, France
Much concern has been raised about the decline in the European eel (Anguilla anguilla) population. European management plans for the recovery of the stock are now in preparation, the main objective being to increase the escapement of the potential spawners (silver eels) in each basin to allow 40% of the pristine biomass to escape. However, there are relatively few studies on silver eel escapement and production, and no recent measurement of escapement in lagoons, habitats which support large silver eel sub-populations in the Mediterranean region. A mark-recapture study was carried out in autumn 2007 in order to estimate the number of silver eels migrating from the Bages-Sigean lagoon in the South-West of France. The migrating population, mostly males between 36 and 42 cm, was estimated to be around 1 120 000 eels (30 kg.ha(-1)). The exploitation rate by professional fishermen was around 20% (6 kg.ha(-1)), leading to an escapement level of 80% (24 kg.ha(-1)). The results are discussed regarding the available data in the literature on silver eel escapement.Le déclin de l'anguille européenne Anguilla anguilla est très préoccupant et chaque pays européen a maintenant le devoir de préparer un plan de gestion pour la reconstitution du stock. Le principal objectif est d'assurer un taux d'échappement d'au moins 40 % de la biomasse pristine des anguilles argentées (futurs géniteurs) vers leur lieu de reproduction. Cependant, très peu de recherches ont été menées sur l'estimation du stock et du taux d'échappement des anguilles argentées et aucune estimation récente du taux d'échappement n'avait encore été réalisée en Méditerranée. Cette étude de marquage-recapture a été réalisée en automne 2007 dans le but d'estimer la quantité d'anguilles argentées migrantes de la lagune de Bages-Sigean. La population migrante, principalement des mâles entre 36 et 42 cm, a été estimée à 1 120 000 anguilles (30 kg·ha1). Le taux d'exploitation par les pêcheurs professionnels évalué à 20 % (6 kg·ha1) laisse suggérer un taux d'échappement de 80 % (24 kg·ha1). Les résultats sont discutés au regard de la littérature disponible sur l'échappement des anguilles argentées
Composition of fish communities in macrotidal salt marshes of the Mont Saint-Michel bay (France)
At least 100 fish species are known to be present in the intertidal areas (estuaries, mudflats and salt marshes) of Mont Saint-Michel Bay. These and other comparable shallow marine coastal waters, such as estuaries and lagoons, play a
nursery role for many fish species. However, in Europe little attention has been paid to the value of tidal salt marshes for fishes. Between March 1996 and April 1999, 120 tides were sampled in a tidal creek. A total of 31 species were caught. This community was largely dominated by mullets (Liza ramada represent 87% of the total biomass) and sand gobies(Pomatoschistus minutus and P. lozanoi represent 82% of the total numbers). These species and also Gasterosteus aculeatus, Syngnathus rostellatus, Dicentrarchus labrax, Mugil spp., Liza aurata and Sprattus sprattus were the most frequent species (>50% of monthly frequency of occurrence). In Europe, salt marshes and their creeks are flooded only during high spring tides. So, fishes only invade this environment during short immersion periods, and no species can be considered as marsh
resident. But, the salt marsh was colonized by fish every time the tide reached the creek, and during the short time of flood, dominant fishes fed actively and exploited the high productivity. Nevertheless, this study shows that there is little interannual variation in the fish community and there are three ‘ seasons ’ in the fish fauna of the marsh. Marine straggler and marine estuarine dependent species colonize marshes between spring (recruitment period in the bay) and autumn before returning into deeper adjacent waters. Estuarine fishes are present all year round with maximum abundances in the end of summer. The presence of fishes confirms that this kind of wetland plays an important trophic and nursery role for these species. Differences in densities and stages distribution of these species into Mont Saint-Michel systems (tidal mudflats, estuaries and tidal salt marshes) can reduce the trophic competition
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