|
|
|
Registros recuperados: 17 | |
|
|
Giannoulaki, Marianna; Petitgas, Pierre; Barra, Marco; Tugores, Pilar; Vasapollo, C.; Iglesias, M.; Leonori, Iole; De Felice, Andrea; Bonanno, A.; Basilone, G.; Mazzola, Salvatore; Bigot, Jean-louis; Machias, Athanassios; Pyrounaki, Maria M.. |
A spatial indicator—the spreading area index—is used to describe anchovy and sardine spatial distribution in relation to biomass variation and to look for ecosystem differences within the Mediterranean basin. Specifically, the variation in the spreading area index in relation to biomass was examined for different areas of the Mediterranean Sea (i.e. Aegean Sea, western Adriatic Sea, Strait of Sicily, Gulf of Lion, and Spanish Mediterranean waters). In order to capture the spatial variability of the population at different levels of fish density, acoustic survey data for the years of highest, lowest, and intermediate abundance were used. In a subsequent step standardized values of spreading area and biomass were estimated to allow comparisons. Results... |
Tipo: Text |
Palavras-chave: Anchovy; Mediterranean Sea; Sardine; Spreading area index. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00114/22549/20245.pdf |
| |
|
|
Beaubrun, Pierre; Roos, David; Astruc, Guillelme; Conejero, Sandrine; Renard, Delphine; Bigot, Jean-louis; Liorzou, Bernard; Le Corre, Gildas; Mellon, Capucine. |
Cette étude présente les espèces et les peuplements de petits poissons pélagiques rencontrés au sein du golfe du Lion, ainsi que les espèces d’oiseaux marins qui y sont associées. Les données ont été collectées durant les campagnes à la mer PELMED (été) et JUVALION (hiver) de 1994 à 2010. Tout au long des différents chapitres, les analyses suivent un plan montrant successivement, pour les petits poissons pélagiques comme pour les oiseaux marins, les proportions relatives des différents groupes d’espèces composant chacun des peuplements étudiés puis, au sein de chacun de ces groupes, les distributions relatives de chacune des espèces observées. La cartographie et l’analyse des données présentées dans le présent rapport englobent d’une part toute la zone... |
Tipo: Text |
|
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00455/56628/58364.pdf |
| |
|
| |
|
| |
|
|
Giannoulaki, Marianna; Pyrounaki, Maria M.; Liorzou, Bernard; Leonori, Iole; Valavanis, Vasilis D.; Tsagarakis, Konstantinos; Bigot, Jean-louis; Roos, David; De Felice, Andrea; Campanella, Fabio; Somarakis, Stylianos; Arneri, Enrico; Machias, Athanassios. |
Identification of potential juvenile grounds of short-lived species such as European sardine (Sardina pilchardus) in relation to the environment is a crucial issue for effective management. In the current work, habitat suitability modelling was applied to acoustic data derived from both the western and eastern part of the Mediterranean Sea. Early summer acoustic data of sardine juveniles were modelled using generalized additive models along with satellite environmental and bathymetry data. Selected models were used to construct maps that exhibit the probability of presence in the study areas, as well as throughout the entire Mediterranean basin, as a measure of habitat adequacy. Areas with high probability of supporting sardine juvenile presence... |
Tipo: Text |
Palavras-chave: Generalized additive models; Habitat suitability modelling; Mediterranean Sea; Potential juvenile habitat; Sardine juveniles; Small pelagic fish. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00043/15390/12822.pdf |
| |
|
|
Bigot, Jean-louis. |
An easy and fast identification method concerning Cancer pagurus , Macropipus puber, ,Atelecyclus rotundatus and Macropipus spp. zoaes is presently describe in that paper. For this purpose we have settled our study on pigmentation test and specific morphological characters. After a critical examination of actual identification keys, we propose new and easy identification tests discribe in a simplified dichotomic key. This paper is completed by some photographies data in order to allow a best approach of characters determination. NOT CONTROLLED OCR |
Tipo: Text |
|
Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/1979/acte-3909.pdf |
| |
|
|
Labelle, Marc; Hoch, Thierry; Liorzou, Bernard; Bigot, Jean-louis. |
Sampling operations are not routinely conducted in France to monitor the landings of bluefin tuna caught by purse seiners in the Mediterranean. The length, weight and age frequencies of bluefin caught by this fleet are predicted based on sale records, length-at-age and weight-length relations, trends in fishing and natural mortality rates, and other ancillary data. The resulting length frequencies are more accurate than those predicted by Liorzou and Bigot (1992) using a simpler algorithm, and are spread more evenly across adjacent size classes. Catch-per-unil-effort (CPUE) was expressed as the numbers of age 2 bluefin caught per successful seine fishing trip in the Gulf of Lions fall fishery. CPUE indices were computed by several methods, and compared to... |
Tipo: Text |
Palavras-chave: Thon rouge; Senne tournante; Prises-par-unité-d'effort; Indices d'abondance; Taux de croissance; Évaluation des stocks; Mer Méditerranée; Bluefin tuna; Purse seine; Catch-per-unit-effort; Abundance indices; Growth rates; Stock-assessment; Mediterranean sea. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00188/29880/28357.pdf |
| |
|
|
Brosset, Pablo; Menard, Frederic; Fromentin, Jean-marc; Bonhommeau, Sylvain; Ulses, Caroline; Bourdeix, Jean-herve; Bigot, Jean-louis; Van Beveren, Elisabeth; Roos, David; Saraux, Claire. |
Endogenous and environmental variables are fundamental in explaining variations in fish condition. Based on more than 20 yr of fish weight and length data, relative condition indices were computed for anchovy and sardine caught in the Gulf of Lions. Classification and regression trees (CART) were used to identify endogenous factors affecting fish condition, and to group years of similar condition. Both species showed a similar annual cycle with condition being minimal in February and maximal in July. CART identified 3 groups of years where the fish populations generally showed poor, average and good condition and within which condition differed between age classes but not according to sex. In particular, during the period of poor condition (mostly recent... |
Tipo: Text |
Palavras-chave: Anchovy; Sardine; Relative condition factor; NW Mediterranean Sea; Endogenous effect; Environmental effect. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00272/38334/36575.pdf |
| |
|
|
Brosset, Pablo; Fromentin, Jean-marc; Menard, Frederic; Pernet, Fabrice; Bourdeix, Jean-herve; Bigot, Jean-louis; Van Beveren, Elisabeth; Perez Rodia, Maria A.; Choy, Sandrine; Saraux, Claire. |
As condition is a key variable in population dynamics (especially for survival, growth and reproduction), the use of well-defined and accurate fish condition indices is capital. In particular, condition indices (morphometric, bioenergetic and biochemical) have never been compared and validated for the European anchovy Engraulis encrasicolus, the European pilchard Sardina pilchardus and the European sprat Sprattus sprattus. The accuracy of two indirect methods, the morphometric relative condition index Kn and the bioenergetics index determined with the Distell Fish Fatmeter was investigated by comparing with a direct measure of relative lipid content carried out with a thin layer chromatography-flame ionization detector. Estimations from the fatmeter... |
Tipo: Text |
Palavras-chave: Anchovy; Fatmeter; Lipids; Mediterranean Sea; Sardine; Sprat. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00226/33741/32304.pdf |
| |
|
|
Ospina-alvarez, Andres; Bernal, Miguel; Alberto Catalan, Ignacio; Roos, David; Bigot, Jean-louis; Palomera, Isabel. |
To date, there are numerous transport simulation studies demonstrating the relevance of the hydrodynamics for the advection, dispersion and recruitment of early stages of marine organisms. However, the lack of data has conditioned the use of realistic locations for the model setup and configuration in transport studies. This work (I) demonstrates the key role played by the use of the realistic initial position of the eggs of small pelagic fishes in the analysis of late-larval recruitment in coastal nursery areas and (II) provides a general solution for deriving future egg positions and abundances from adult biomass obtained from acoustic surveys and available fecundity data. Using European anchovy in the NW Mediterranean as a case study, we first analyzed... |
Tipo: Text |
|
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00160/27119/25312.pdf |
| |
|
|
Van Beveren, Elisabeth; Bonhommeau, Sylvain; Fromentin, Jean-marc; Bigot, Jean-louis; Bourdeix, Jean-herve; Brosset, Pablo; Roos, David; Saraux, Claire. |
Since 2007, the ecosystem of the Gulf of Lions has shifted to a different regime, characterised by a low anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) biomass and a remarkably high sprat (Sprattus sprattus) biomass. Surprisingly, the abundance and recruitment of anchovy and sardine remained high. To understand which processes (bottom-up or top-down control, etc.) could have caused this shift, we studied the changes in body condition, growth and size and age of anchovy, sardine and sprat over 1984–1985 and 1992–2012, using data from scientific surveys. The annual age structure of anchovy and sardine was estimated using Bayesian mixture models based on size frequency data with priors on the age–length relationship derived from independent... |
Tipo: Text |
|
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00192/30335/29917.pdf |
| |
|
| |
|
|
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 |
|
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00035/14656/11956.pdf |
| |
|
|
Saraux, Claire; Fromentin, Jean-marc; Bigot, Jean-louis; Bourdeix, Jean-herve; Morfin, Marie; Roos, David; Van Beveren, Elisabeth; Bez, Nicolas. |
Understanding the ecological and anthropogenic drivers of population dynamics requires detailed studies on habitat selection and spatial distribution. Although small pelagic fish aggregate in large shoals and usually exhibit important spatial structure, their dynamics in time and space remain unpredictable and challenging. In the Gulf of Lions (north-western Mediterranean), sardine and anchovy biomasses have declined over the past 5 years causing an important fishery crisis while sprat abundance rose. Applying geostatistical tools on scientific acoustic surveys conducted in the Gulf of Lions, we investigated anchovy, sardine and sprat spatial distributions and structures over 10 years. Our results show that sardines and sprats were more coastal than... |
Tipo: Text |
|
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00226/33739/32151.pdf |
| |
|
|
Pethybridge, H.; Bodin, Nathalie; Arsenault-pernet, E. -j.; Bourdeix, Jean-herve; Brisset, Blandine; Bigot, Jean-louis; Roos, David; Peter, M.. |
We describe the total lipid content, lipid class composition and fatty acid profiles of adult forage fishes (anchovy, sardine and sprat) sampled in the NW Mediterranean Sea in 2010 and 2011. Inter-and intra-species differences were mostly related to sampling period with limited effect of gender or total length. As an assemblage, total lipid content and relative levels of triacylglycerols and fatty acids 16:1n7, 20:5n3 and 14:0 in forage fish were highest in summer and autumn, indicating better feeding conditions and a more pronounced diatom-supported food web. In contrast, total lipid content was lowest at the end of winter and spring, and coincided with high levels of 22:6n3, indicating a more herbivorous diet based on dinoflagellates. Resource... |
Tipo: Text |
Palavras-chave: Trophic markers; Environmental variations; Clupeiformes; Nutritional condition; Prey quality; Ecosystem health. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00239/34997/33530.pdf |
| |
|
|
Le Bourg, B.; Banaru, Daniela; Saraux, Claire; Nowaczyk, A.; Le Luherne, E.; Jadaud, Angelique; Bigot, Jean-louis; Richard, P.. |
Increasing abundance of non-commercial sprats and decreasing biomass and landings of commercial anchovies and sardines justify the need to study the feeding ecology and trophic niche overlap of these planktivorous species in the Gulf of Lions. Their diet has been investigated on the basis of stomach content and stable isotope analyses in 2011 and 2012 according to different depths and regions in the study area. The main prey were Corycaeidae copepods, Clauso/Paracalanus, Euterpina acutifrons and Microsetella, for sprats and small copepods, such as Microsetella, Oncaea and Corycaeidae, for anchovies and sardines. This is the first time that the diet of sprats is described in the Gulf of Lions. Sprats fed on a larger size spectrum of prey and seem to be more... |
Tipo: Text |
Palavras-chave: Anchovies; Sardines; Sprats; North-western Mediterranean sea; Stomach contents; Stable isotopes. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00272/38314/38625.pdf |
| |
|
|
Banaru, Daniela; Mellon, Capucine; Roos, David; Bigot, Jean-louis; Souplet, Arnauld; Jadaud, Angelique; Beaubrun, P.; Fromentin, Jean-marc. |
The Gulf of Lions ecosystemwas described using the Ecopath mass-balancemodel to characterise its structure and functioning and to examine the effects of themultispecific fisheries operating in this area. The model is composed of 40 compartments, including 1 group of seabirds, 2 groups of etaceans, 18 groups of fish, 12 groups of invertebrates, 5 groups of primary producers, detritus and discards. Input datawere based on several recurrent scientific surveys, two alternative datasets for fishing data, stock assessment outputs, stomach content analyses and published information. Results showed that the functional groups were organised into five trophic levels with the highest one represented by dolphins, anglerfish, Atlantic bluefin tuna, European hake and... |
Tipo: Text |
Palavras-chave: Gulf of Lions; Ecopath with Ecosim; Food web; Fishing impacts. |
Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00116/22758/20614.pdf |
| |
Registros recuperados: 17 | |
|
|
|