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Registros recuperados: 48 | |
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Le Goff, Clement; Lavaud, Romain; Cugier, Philippe; Jean, Fred; Flye-sainte-marie, Jonathan; Foucher, Eric; Desroy, Nicolas; Fifas, Spyros; Foveau, Aurelie. |
In this paper we used a modelling approach integrating both physical and biological constraints to understand the biogeographical distribution of the great scallop Pecten maximus in the English Channel during its whole life cycle. A 3D bio-hydrodynamical model (ECO-MARS3D) providing environmental conditions was coupled to (i) a population dynamics model and (ii) an individual ecophysiological model (Dynamic Energy Budget model). We performed the coupling sequentially, which underlined the respective role of biological and physical factors in defining P. maximus distribution in the English Channel. Results show that larval dispersion by hydrodynamics explains most of the scallop distribution and enlighten the main known hotspots for the population,... |
Tipo: Text |
Palavras-chave: Population dynamic model; Ecophysiological model; English Channel; Pecten maximus; Spatial distribution. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00355/46642/46467.pdf |
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Pitel, Mathilde; Berthou, Patrick; Fifas, Spyros. |
Basically, a dredge is a bottom-towed gear and consists of a metal frame with a blade or teeth, to dig into the sediment and extract the shelled molluscs, and a mesh bag to collect the catch. Whereas hand dredging is observed on some intertidal beds (Donax trunculus in France), the use of dredge generally needs a fishing boat. There is a great diversity of dredge types, with specific designs used to target different species in particular beds: Manual dredges for Donax (Donax trunculus), Warty venus (Venus verrucosa) and clams (Venerupis pulastra, Ruditapes sp) Dredges for King scallops (Pecten maximus) Dredges for Warty venus (Venus verrucosa) Dredge for Queen scallops (black and white, Chlamys varia and Chlamys opercularia) Dredges for small... |
Tipo: Text |
Palavras-chave: Management; Environmental impact; Spisula; Bittersweet palourdi; Fishing boat; Clam; Dredge; Brittany; Gestion; Impact environnemental; Spisula; Amande; Navire de pêche; Drague; Bretagne. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/rapport-4608.pdf |
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Fifas, Spyros; Biseau, Alain. |
Les simulations réalisées, même si elles restent théoriques, font apparaitre très clairement que l’obligation de débarquement d’une espèce pour laquelle le taux de survie des rejets est non nul conduit à une augmentation de la mortalité par pêche. Pour la langoustine, à terme et selon le taux de survie actuel retenu, et sans modification de la sélectivité, la hausse de mortalité par pêche est de 8-10%, la baisse de la biomasse féconde de 12 – 14% et celle des débarquements de 12 – 14% également. Il faut rappeler que, compte tenu du diagramme d’exploitation actuel, toute amélioration de la sélectivité (au sens large du terme) conduirait à une amélioration substantielle du stock et des débarquements, même si la totalité des rejets mourait du fait de... |
Tipo: Text |
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Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00299/41019/40125.pdf |
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Laurans, Martial; Fifas, Spyros; Demaneche, Sebastien; Brerette, Stéphane; Debec, Olivier. |
Fishers from Le Croisic (France) measure all the lobsters (Homarus gammarus) they capture, indicating their sex and whether the females are ovigerous or non-ovigerous. Between 2003 and 2006 and mainly between April and September, 16 884 lobsters were measured in this manner. These self-sampled data were used to study catchability and functional maturity of lobsters. The sex ratio was 50%, and catchability did not change if a female was ovigerous or non-ovigerous. With the help of a logistic function, a relationship was established between body size and the proportion of ovigerous females. For the study area, 100% of the females were mature upon reaching a carapace length (CL) of 115 mm, and the proportion of ovigerous females reached 70% each year. The L50... |
Tipo: Text |
Palavras-chave: Self sampling; Homarus gammarus; Functional maturity; Catchability. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7319.pdf |
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Briton, Florence; Macher, Claire; Merzereaud, Mathieu; Legrand, Christelle; Fifas, Spyros; Thebaud, Olivier. |
Well-established single-species approaches are not adapted to the management of mixed fisheries where multiple species are simultaneously caught in unselective fishing operations. In particular, ignoring joint production when setting total allowable catches (TACs) for individual species is likely to lead to over-quota discards or, when discards are not allowed, to lost fishing opportunities. Furthermore, economic and social objectives have been poorly addressed in the design of fisheries harvest strategies, despite being an explicit objective of ecosystem-based fisheries management in many jurisdictions worldwide. We introduce the notion of operating space as the ensemble of reachable, single-species fishing mortality targets, given joint production in a... |
Tipo: Text |
Palavras-chave: Eco-viability; Mixed fisheries management; Bio-economic modelling; Integrated TAC advice. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00624/73614/73030.pdf |
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Biseau, Alain; Bellail, Robert; Bertignac, Michel; Biais, Gerard; Bigot, Jean-louis; Bouche, Ludovic; Bourjea, Jerome; Caro, Anthony; De Casamajor, Marie-noelle; Caill-milly, Nathalie; Drogou, Mickael; Duhamel, Erwan; Fifas, Spyros; Foucher, Eric; Fromentin, Jean-marc; Jadaud, Angelique; Lampert, Luis; Laurans, Martial; Lissardy, Muriel; Lorance, Pascal; Mahe, Jean-claude; Mahe, Kelig; Masse, Jacques; Morandeau, Gilles; Pawlowski, Lionel; Poisson, Francois; Reynal, Lionel; Roos, David; Verin, Yves; Vermard, Youen; Vigneau, Joel. |
Ce document présente l'état des principaux stocks exploités par les flottes françaises en termes de mortalité par pêche et de biomasse de reproducteurs. La situation fin 2010 (début 2011) par rapport aux points de référence (de précaution et Fmsy) est indiqué lorsque les indicateurs sont estimés et que les références sont définies. Les grandes tendances en matière d'évolution des mortalités et biomasses sont également indiquées. |
Tipo: Text |
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Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00035/14656/11956.pdf |
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Doyen, Luc; Thebaud, Olivier; Bene, Christopher; Martinet, V.; Gourguet, S.; Bertignac, Michel; Fifas, Spyros; Blanchard, Fabian. |
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... |
Tipo: Text |
Palavras-chave: Ecosystem based fisheries management; Viability; Stochastic; Nephrops; Hake. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00074/18571/16153.pdf |
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Guillen, Jordi; Macher, Claire; Merzereaud, Mathieu; Fifas, Spyros; Guyader, Olivier. |
MSY objectives are being adopted as major fisheries management targets worldwide. However, in fisheries where discards account for an important share of the catches, the yield, effort, and biomass at MSY can be significantly different when accounting or not for discards and thus when, basing the yield estimations on landings or catches. Also whether accounting for a certain survival rate, of discards can lead to different MSY targets estimates. Hence, both decisions have important, implications on catch and effort reduction recommendations, and consequently on the quota, calculations for fisheries managed by quotas. Results from the Bay of Biscay nephrops fishery confirm, that the optimal exploitation level can vary significantly when optimising for... |
Tipo: Text |
Palavras-chave: Maximum Sustainable Yield (MSY); Discards; Nephrops; Survival rate. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00201/31180/29867.pdf |
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Thebaud, Olivier; Veron, Gerard; Fifas, Spyros. |
The commercial fishery for wedge clam, or telline (Donax trunculus) in the bay of Douarnenez in France started in the early 1980ies. During twenty years, the activity has developed, from an opportunistic fishery, into a regular fishing enterprise for 36 fishermen, who derive from it most, if not all, of their revenue. The fishery is nowadays strictly regulated. It is subject to natural variations in the productivity of clam stocks, in relation with meteorological conditions which can strongly affect the stocks. The bay of Douarnenez has been experiencing regular blooms of harmful algae, both of species leading to shellfish poisoning for human consumption, such as Dinophysis (Diarrhoeic Shellfish Poisoning) and Pseudo-nitzschia (Amnesic Shellfish... |
Tipo: Text |
Palavras-chave: Temporary fishing ban; Mortality; Economic impact; Fishery; Wedge clam; Donax trunculus; Fermeture temporaire; Mortalité; Impact; Pêcherie; Telline; Donax trunculus. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/rapport-1262.pdf |
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Foucher, Eric; Blanchard, Michel; Cugier, Philippe; Desroy, Nicolas; Dreanno, Catherine; Fauchot, Juliette; Fifas, Spyros; Guyader, Olivier; Jean, Frederic; Le Gallic, Bertrand; Riou, Philippe; Schapira, Mathilde; Thiebaut, Eric. |
The King scallop Pecten maximus constitutes the first landed species in terms of tonnage and the second or third one in terms of value for the French fisheries. More than 90% of these landings come from the English Channel indicating that its exploitation is essential to local fleets. The COMANCHE project (Ecosystem Interactions and anthropogenic impacts on King scallops populations in the English Channel) proposed to improve the knowledge of the scallop within the Channel, through an ecosystem-based approach for fisheries, appealing to a wide range of scientific disciplines (physics, chemistry, genetics, ecology, geostatistics, modeling, economics ....). Researches on the spatial location of scallop beds, connectivity by larval dispersal between beds,... |
Tipo: Text |
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Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00251/36236/34797.pdf |
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Registros recuperados: 48 | |
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