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| Registros recuperados: 173 | |
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| Marchal, Emile; Petitgas, Pierre. |
| The gulf of Cariaco, Venezuela, is a rather isolated piece of coastal ocean where spatio-temporal variability has been measured. In 1986, three repeated surveys have been carried out in this gulf. The important differences in biomass estimates are attributed to sampling error only. The biological nature of this variability is studied. It is due to a high concentration of the biomass in a few schools and correlatively to the hit or the miss of these large schools, during the sampling. Structural information for predicting them is sought. Also, the number of schools per elementary sampling distance unit (ESDU) and the biomass in each school were measured by echointegration. It is found that there is no clear relation between these two variables. Thus their... |
| Tipo: Text |
Palavras-chave: Evaluation des stocks; Campagnes acoustiques; Précision; Stock assessment; Echo surveys; Reliability. |
| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00190/30077/28565.pdf |
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| Kell, Laurence T.; Mosqueira, I; Grosjean, P; Fromentin, Jean-marc; Garcia, D; Hillary, R; Jardim, E; Mardle, S; Pastoors, M.a; Poos, J.j.; Scott, F; Scott, R. |
| The FLR framework (Fisheries Library for R) is a development effort directed towards the evaluation of fisheries management strategies. The overall goal is to develop a common framework to facilitate collaboration within and across disciplines (e.g. biological, ecological, statistical, mathematical, economic, and social) and, in particular, to ensure that new modelling methods and software are more easily validated and evaluated, as well as becoming widely available once developed. Specifically, the framework details how to implement and link a variety of fishery, biological, and economic software packages so that alternative management strategies and procedures can be evaluated for their robustness to uncertainty before implementation. The design of the... |
| Tipo: Text |
Palavras-chave: Uncertainty; Stock assessment; Software; Simulation framework; Precautionary approach; Open source; Management strategy evaluation; Bio economic modelling. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2732.pdf |
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| Ducrotoy, J; Desprez, M; Elkaim, B. |
| The recent collapse in the landings of cockles (Cerastoderma edule) from the Bay of Somme (France) required to investigate if a change in the environmental factors was liable for the drop of the bivalve populations. This project has led to a preliminary assessment of the situation and has been drawn up from the data collected by the Groupe d'Etude des Milieux Estuariens et Littoraux since 1978. It relies on the survey of the spatio-temporal changes of bio-facies. it is suggested that the impact of changes in sediment characteristics is important as well as competition with species as Pygospio elegans (Polychaeta). The above parameters are assessed as essential in the fluctuations of the cockle numbers but they do not explain entirely the collapse in the... |
| Tipo: Text |
Palavras-chave: Landing statistics; Clam fisheries; Stock assessment; Population dynamics; Marine mollusks. |
| Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/publication-1784.pdf |
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| Archarnbault, Benoit; Le Pape, Olivier; Baulier, Loic; Vermard, Youen; Veron, Matthieu; Rivot, Etienne. |
| We explore how alternative hypotheses on the degree of mixing among local subpopulations affect statistical inferences on the dynamics and stock assessment of a harvested flatfish population, namely, the common sole population in the Eastern Channel (ICES area VIId). The current paradigm considers a single, well-mixed, spatially homogeneous population with juveniles from all coastal nursery grounds along the French and UK coasts that contribute to a single adult population and one pool of eggs. Based on the available data and ecological knowledge, we developed a spatial Bayesian integrated life-cycle model that consists of three subpopulations (one near the UK coast and two near the French coast, denoted UK, West FR and East FR, respectively) supported by... |
| Tipo: Text |
Palavras-chave: Solea solea; Spatial life-cycle model; Coastal nurseries; Connectivity; Stock assessment; Hierarchical bayesian model. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00333/44430/44231.pdf |
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| Bertignac, Michel; De Pontual, Helene. |
| The results of a pilot tagging study on hake (Merluccius merluccius), conducted in the northern part of the Bay of Biscay in 2002, indicate that growth rates for this stock may be currently underestimated because of biased estimates of age. The impact that such a bias may have on the stock dynamics and the trends of the key population parameters, recruitment, spawning-stock biomass (SSB), and mortality are investigated. Assuming new growth parameters, a new age-length key is derived and used to produce and catch-at-age data and abundance indices, which are then used to assess the stock. Bias in estimating age affects the absolute levels of fishing mortality and stock biomass estimates, and also impacts the trend in SSB. However, trends in fishing mortality... |
| Tipo: Text |
Palavras-chave: Tagging; Stock assessment; Simulation; Management; Growth; European hake; Age estimation. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2824.pdf |
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| Gros, Philippe; Santarelli, Leonardo. |
| The experimental design of the capture field area of baited whelk-pots involves, as a controlled factor, four different spacings between pots (6, 12, 24 and 36m), randomly distributed along a ground line. This spectrum of values is sufficiently broad to preclude overlap of capturing fields of sorne pots. Taking account of the patterns of the M2 tidal currents in the area studied, an ellipse was chosen as a geometrical model of the shape of the capture field. Semimajor and semiminor axes were estimated by least squares, the expected catch per pot being defined as a decreasing function of the area of overlap with adjacent capture fields. · Experimental fishing of Buccinum undatum L. was carried out in the Channel Isles region (Western Channel), and provided... |
| Tipo: Text |
Palavras-chave: Échantillonnage quantitatif; Estimation de densité; Casier appâté; Gestion de stocks; Buccin; Quantitative sampling; Density estimate; Baited pot; Stock assessment; Whelk. |
| Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00112/22279/19954.pdf |
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| Lazard, Coline; Verin, Yves; Auber, Arnaud. |
| IBTS surveys (International Bottom Trawl Survey) are carried out within an international framework. Main countries bordering the North Sea participate to it according to the European Community regulations (EC N°1543/2000 and N° 1639/2001) which specify that countries from E.U. have to carry out surveys at sea in order to evaluate abundance and stocks distribution, independently of commercial fisheries data. The first target of the IBTS survey is to have a diagnosis on the main commercial fish stock and to calculate abundances index by age for these species. This survey started in the years 70’s and gradually standardised. Since the years 80’s, a common protocol is implemented and used by all participants. The same fishing gear and the same working methods... |
| Tipo: Text |
Palavras-chave: North sea; GOV; Beam trawl; MIK; Abundance; Stock assessment. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00655/76740/77891.pdf |
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| Desprez, M; Ducrotoy, J; Elkaim, B. |
| In this paper, the results collected since 1978 on the cockle (Cerastoderma edule) in the Bay of Somme have been recapitulated. A synthesis is brought up about causes of the bivalve population collapse which was portended as early as 1982 from the animal cinetics study. In order to back up the discussion, the main results dealing with the biology and ecology of the species are recalled in illustrated form. A review of the international literature leads to a comment upon the diagrams. A comparison with data from European estuaries tends to take climatic and oceanic disturbances into account as well as local pollution such as eutrophication which is probable on the littoral of Picardy. |
| Tipo: Text |
Palavras-chave: Clam fisheries; Stock assessment; Recruitment; Population dynamics; Marine mollusks. |
| Ano: 1985 |
URL: http://archimer.ifremer.fr/doc/1985/publication-1783.pdf |
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| Gascuel, Didier; Coll, Marta; Fox, Clive; Guenette, Sylvie; Guitton, Jerome; Kenny, Andrew; Knittweis, Leyla; Nielsen, J. Rasmus; Piet, Gerjan; Raid, Tiit; Travers-trolet, Morgane; Shephard, Samuel. |
| Stock-based and ecosystem-based indicators are used to provide a new diagnosis of the fishing impact and environmental status of European seas. In the seven European marine ecosystems covering the Baltic and the North-east Atlantic, (i) trends in landings since 1950 were examined; (ii) syntheses of the status and trends in fish stocks were consolidated at the ecosystem level; and (iii) trends in ecosystem indicators based on landings and surveys were analysed. We show that yields began to decrease everywhere (except in the Baltic) from the mid-1970s, as a result of the over-exploitation of some major stocks. Fishermen adapted by increasing fishing effort and exploiting a wider part of the ecosystems. This was insufficient to compensate for the decrease in... |
| Tipo: Text |
Palavras-chave: Ecosystem approach to fisheries management; Ecosystem indicators; Good environmental status; Marine Strategy Framework Directive; Stock assessment; Trophic level. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00201/31256/29910.pdf |
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| Foucher, Eric. |
| The assessment of the King scallop stock of the Bay of Seine (Pecten maximus) was carried out in July 2019, in the Bay of Seine sensu stricto, located in French territorial waters (from the Normandy coast to the south to the limit of 12 nautical miles to the North), as well as the bordering zone lying north of this 12-mile limit and up to a latitude of 49°48N to the North, called "Extérieur Baie de Seine". For this, a scientific survey, based on a stratified random sampling plan, was conducted aboard the F/R Thalia, a coastal research vessel of the French Oceanographic Fleet. Nearly 170 sampling points were completed in the whole area. Analysis of these data leads to an overall increase in exploitable biomass over the entire area. Outside the Bay of Seine,... |
| Tipo: Text |
Palavras-chave: Coquille Saint-Jacques; Pecten maximus; Manche Est; Baie de Seine; Evaluation de stock; King scallop; Pecten maximus; Eastern Channel; Bay of Seine; Stock assessment. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00516/62739/67128.pdf |
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| Registros recuperados: 173 | |
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