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Registros recuperados: 41 | |
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Masse, Jacques. |
Eight acoustic surveys were carried our in the Bay of Biscay, during 1989-94, to study the distribution and abundance of anchovy (Engraulis encrasicolus, L.) in that area. Acoustic data were stored using the INES/MOVIES acquisition and processing system. Species-specific distribution patterns were confirmed through complementary sampling with a mid-water trawl. This paper summarises the combination of technical procedures used for acoustic assessments, and the results of acoustic surveys in the Bay of Biscay that pertain to the dynamics of this stock. Information is presented on the distribution and abundance of anchovy and co-occuring species, and on the movement patterns detected within the pelagic fish community, in relation to environmental conditions.... |
Tipo: Text |
Palavras-chave: Acoustic; Anchovy; Engraulis encrasicolus; Schooling; Pelagic; Behaviour; Bay of Biscay. |
Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00191/30265/28719.pdf |
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Doray, Mathieu; Petitgas, Pierre; Masse, Jacques. |
Estimer la biomasse d'un stock de poissons par acoustique nécessite de combiner des données de nature diverse collectées le long du parcours d'échantillonnage (Woillez et al., 2009). Il s'agit essentiellement de combiner trois champs de données spatialisées : une carte de densités acoustiques attribuées aux poissons, une carte de proportions d'espèces et une carte de longueurs moyennes. |
Tipo: Text |
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Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00003/11447/7997.pdf |
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Silva, A.; Skagen, D. W.; Uriarte, A.; Masse, Jacques; Santos, M. B.; Marques, V.; Carrera, P.; Beillois, Pierre; Pestana, G.; Porteiro, C.; Stratoudakis, Y.. |
The spatio-temporal variability in the distribution, demographic structure, recruitment, and mortality of sardine within the Iberian Biscay region is described using area-disaggregated data collected during acoustic surveys and at ports since the mid-1980s. Multiple regression models were used to describe log numbers-at-age obtained annually in ten areas covered by three surveys to test the existence of geographic differences in selectivity-at-age, recruitment strength, and mortality and to infer plausible migration routes. Within Iberian waters, sardine biomass was mainly concentrated off western Portugal and the Gulf of Cadiz. In the Bay of Biscay, biomass levels were comparable with those off western Portugal. Recruitment was localized in a few areas... |
Tipo: Text |
Palavras-chave: Stock structure; Small pelagic fish; Population dynamics; Iberian Peninsula. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6459.pdf |
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Duhamel, Erwan; Biseau, Alain; Masse, Jacques; Villalobos, Hector. |
The french fishery of anchovy is divided in two groups defined by gears : purse seine and pelagic trawl. The average length of these vessels is about 20m. This fleet is very opportunistic : all trawlers are using several trawls during the year, to catch sometimes bass, tuna, hake, or scampi, and purse seine are mainly fishing sardine. Each year, the main anchovy catches are provided by pair trawlers. Purse seiners operate often in coastal areas (<10 nautical miles); trawlers may operate until 50 nautical miles offshore but are banned inside the three miles coastal zone. The pair trawlers may operate from Basque country to western Channel according to fish availability. Purse seiners usually stay around their home harbour. |
Tipo: Text |
Palavras-chave: Pelagic trawl; Purse seine; Anchovy; Bay of Biscay; Acoustic; Survey; ICES; PELGAS; Chalut pelagic; Bolinche; Anchois; Golfe de Gascogne; Acoustique; Campagne oceanographique; CIEM; PELGAS. |
Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/acte-2296.pdf |
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Petitgas, Pierre; Doray, Mathieu; Masse, Jacques; Grellier, Patrick. |
Fish length frequency histograms from research surveys are of prime importance for identifying habitats of different life stages, as well as for stock assessment. However, no method has thus far been available for mapping these histograms as spatially varying curves. Here, a procedure is applied to map spatially connected curves, and detail is given on how it can be applied to map the length frequency histograms. At each sample location, a fish length frequency histogram is given as a vector of non-independent values. The histogram is first modelled as a polynomial expansion on the basis of orthogonal polynomials. Then, the polynomial coefficients are mapped by co-kriging, after fitting a model of co-regionalization. The length frequency map is finally... |
Tipo: Text |
Palavras-chave: Co-kriging; European anchovy; Fish length; Functional kriging; Habitat; Mapping curves. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00049/16042/13581.pdf |
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Doray, Mathieu; Masse, Jacques; Petitgas, Pierre; Trenkel, Verena. |
Le sondeur multifaisceaux Simrad ME70 (ou SMFH) (Trenkel et al., 2008) a été utilisé pour la première fois en routine en parallèle des sondeurs monofaisceaux ER60 lors de la campagne Pelgas09 (25/04-05/06/2009). Le premier objectif était de tester la faisabilité d'une utilisation en routine du ME70 lors d'une campagne visant à évaluer par acoustique les stocks d'anchois et de sardine du Golfe de Gascogne. A terme, les données récoltées lors de cette campagne permettront d'étudier l'apport du sondeur multifaisceaux ME70 à l'estimation de biomasse, en comparant les estimations de stocks obtenues en mono et multifaisceaux. Les données acoustiques 3D collectées au moyen du ME70 dans l'ensemble du Golfe de Gascogne lors de Pelgas09 doivent également... |
Tipo: Text |
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Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/rapport-6755.pdf |
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Silva, A; Carrera, P; Masse, Jacques; Uriarte, A; Santos, M; Oliveira, P; Soares, E; Porteiro, C; Stratoudakis, Y. |
This study describes broad-scale spatial variations in sardine growth across the northeastern Atlantic and Mediterranean waters using opportunistic samples collected in recent years. More detailed information on spatial, decadal and seasonal growth variations is provided for the Iberian-Biscay region using data collected in acoustic surveys since the mid-1980s. Growth curves are fitted to annual or monthly length-at-age data using a robust Von Bertalanffy model; parameters for recent samples are compared with literature information using an auximetric plot while differences between areas within the Iberian-Biscay region are tested by log-likelihood ratio tests. Sardine growth performance is generally lower in the Mediterranean and declines across the... |
Tipo: Text |
Palavras-chave: Iberian Biscay region; Spatio temporal variation; Growth; Sardina pilchardus. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4078.pdf |
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Masse, Jacques. |
The objective of PELGAS surveys is to study the abundance and distribution of pelagic fish in the Bay of Biscay. The main target species is anchovy but it will be considered in a multi-specific context. To assess an optimum horizontal and vertical description of the area, two types of actions are combined : 1) Continuous acquisition by storing acoustic data from five different frequencies and pumping sea-water under the surface in order to evaluate the number of fish eggs using a CUFES system (Continuous Under-water Fish Eggs Sampler)), and 2) discrete sampling at stations (by trawls, plankton nets, CTD). Satellite imagery (temperature and sea colour) and modelisation will be also used before and during the cruise to recognise the main physical and... |
Tipo: Text |
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Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/rapport-6433.pdf |
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Bergeron, Jean-pierre; Masse, Jacques. |
Fishermen have long observed the sudden change of shoaling behaviour of small pelagic fish following a strong wind event. The phenomenon was thereafter confirmed by fisheries scientists using acoustic tools. In this study, we report our observations made with acoustics to measure disorganization of the previously observed spatial distribution and shape of shoals that occurred after a wind event. The measurements were made during a fisheries research cruise in the Bay of Biscay (NE Atlantic) aimed at determining i) small pelagic fish species abundance and ii) the individual nutritional state of anchovies (Engraulis encrasicolus L.) via evaluation of their RNA/DNA ratio. A spatial fine-scale study was conducted in two of the main breeding areas for anchovy,... |
Tipo: Text |
Palavras-chave: Engraulis encrasicolus L.; Anchovy; Behaviour; Acoustics; Bay of Biscay; Nutritional condition; RNA/DNA ratio. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00033/14473/11782.pdf |
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Bergeron, Jean-pierre; Masse, Jacques. |
The recruitment of marine fish populations is a central concern of fisheries scientists. Multiple research pathways have been explored, with emphasis of the causes of mortality affecting principally the early developmental stages of fish life. The small data set presented focuses on a feature often inadequately considered, i.e., the nutritional condition of the breeding parent fishes estimated from the levels of the RNA/DNA ratio determined in fish white muscle. This is applied to the European anchovy population inhabiting the French continental shelf of the North-east Atlantic Ocean. In four of the five years analysed, the annual recruitment shows a tight relationship with the mean values for the RNA/DNA ratio determined in the parent fish during the... |
Tipo: Text |
Palavras-chave: Anchovy; Bay of Biscay; Breeding season; Recruitment; RNA/DNA ratio. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00109/22025/19684.pdf |
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Doray, Mathieu; Masse, Jacques; Petitgas, Pierre. |
The main objective of Ifremer's pelagic sea surveys (Pelgas in the Bay of Biscay and Pelmed in the Gulf of Lion) is to assess the biomass of anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) populations, based on fisheries acoustic data. Complementary data on the whole pelagic ecosystem (hydrology, plankton, fish eggs and larvae, other fish species, seabirds and marine mammals) are also collected during the cruises. This document describes the procedures used to derive stock abundance estimates from acoustic and fishing data collected during sea cruises, the Pelgas sea survey being used as an example. |
Tipo: Text |
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Ano: 2010 |
URL: https://archimer.ifremer.fr/doc/00003/11446/7996.pdf |
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Authier, Matthieu; Doremus, Ghislain; Van Canneyt, Olivier; Boubert, Jean-jacques; Gautier, Gerard; Doray, Mathieu; Duhamel, Erwan; Masse, Jacques; Petitgas, Pierre; Ridoux, Vincent; Spitz, Jerome. |
Conservation has moved from species-centered to ecosystem-based approaches: the Marine Strategy Framework Directive requires the maintenance or restoration of ‘Good Environmental Status’ of all European marine waters. Monitoring biodiversity at the scale of whole ecosystems is salient, but challenging owing to the large spatial scale involved and the large spatio-temporal heterogeneity of marine ecosystems. We capitalized on the integrated ecosystemic PELGAS survey carried out in spring in the Bay of Biscay to document patterns of change in marine megafauna relative abundance at the community level over more than a decade (2004-2016). The relative abundance of the twenty three most frequently sighted species (6 cetaceans and 17 seabirds) was estimated by... |
Tipo: Text |
Palavras-chave: Marine megafauna; Relative abundance; MSFD; Ecosystemic surveys. |
Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00403/51405/51981.pdf |
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Masse, Jacques. |
Afler a short review of acoustic principles, methodology and purposes of accustic surveys are described and some examples given. IFREMER instrumentation, strategy and calculations used during echo sur veys are described in details and criticized. Five acouslic sur veys carried o t in the Bay of Biscay between 1983 and 1987 show that several species are generally mixed , and lheir identification is very oflen biased by behaviour phenomena. A new way of classi fying echotraces and interpretating data has been applied to these surveys. The results are summarized in tables and maps. Whenever multispecies structures are concerned, it seems at present impossible to assess absolute biomasses based on acoustic survey method. ln such a situation, acoustic surveys... |
Tipo: Text |
Palavras-chave: Echo-intégration; Golfe de Gascogne; Petits pélagiques; Comportement; Evaluation; Acoutic; Surveys; Bay of Biscay; Pelagic fishes; Behaviour; Assessment. |
Ano: 1988 |
URL: http://archimer.ifremer.fr/doc/00455/56654/58395.pdf |
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Registros recuperados: 41 | |
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