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Auteur Bodin, N.; Tapie, N.; Le Menach, K.; Chassot, E.; Elie, P.; Rochard, E.; Budzinski, H. url  doi
openurl 
  Titre PCB contamination in fish community from the Gironde Estuary (France) : blast from the past Type Article scientifique
  Année 2014 Publication Revue Abrégée Chemosphere  
  Volume 98 Numéro (up) Pages 66-72  
  Mots-Clés Bioindicators; Biomagnification; Fish assemblage; Food safety; Persistent organic pollutants (POPs)  
  Résumé The contamination of the Gironde Estuary, southwest of France, by polychlorinated biphenyls (PCBs) was assessed using six fish of high ecological and economic importance as bioindicator species. The concentrations of 21 PCB congeners and total fat contents were determined in the muscle and liver of eels (Anguilla anguilla), seabass (Dicentrarchus labrax), flounders (Platichthys flesus), meagres (Argyrosomus regius), mullets (Liza ramada), and soles (Solea vulgaris). In addition, information regarding the trophic ecology of the studied fish was obtained through the analysis of carbon and nitrogen stable isotopes (i.e., delta C-13 and delta N-15) in muscle. Results revealed high PCB concentrations in fish compared to monitored European estuaries. The muscle of eels was by far the most contaminated fish flesh (Sigma(7)PCBs = 1000 +/- 440 ng g(-1), on a dry weight basis), while the higher PCB concentrations in liver were measured in flounder (Sigma(7)PCBs = 2040 +/- 1160 ng g(-1), d.w.). A quantile regression approach allowed to investigate the fate of PCBs in the Gironde estuarine fish assemblage, and revealed a general process of trophic magnification. Finally, most of the analysed fish presented PCB concentrations in muscle meat above the current European maximum limits for sea products, while the derived “Toxic Equivalent Quantity” (TEQ) revealed human health concerns only for high-fat fish consumption.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0045-6535 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel LL @ pixluser @ collection 326  
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Auteur Neira, S.; Moloney, C.; Christensen, V.; Cury, P.; Shannon, L.; Arancibia, H. url  doi
openurl 
  Titre Analysing changes in the southern Humboldt ecosystem for the period 1970-2004 by means of dynamic food web modelling Type Article scientifique
  Année 2014 Publication Revue Abrégée Ecological Modelling  
  Volume 274 Numéro (up) Pages 41-49  
  Mots-Clés Ecopath with Ecosim; Fishing patterns; Physical forcing; Regime shifts; Southern Humboldt; Trophic controls  
  Résumé A 22-group Ecopath model representing the southern Humboldt (SH) upwelling system in the year 1970 is constructed. The model is projected forward in time and fitted to available time series of relative biomass, catch and fishing mortality for the main fishery resources. The time series cover the period 1970 to 2004 and the fitting is conducted using the Ecopath with Ecosim (EwE) software version 5.1. The aim is to explore the relative importance of internal (trophic control) and external (fishing, physical variability) forcing on the dynamics of commercial stocks and the Southern Chilean food web. Wide decadal oscillations are observed in the biomass of commercial stocks during the analyzed period. Fishing mortality explains 21% of the variability in the time series, whereas vulnerability (v) parameters estimated using EwE explain an additional 20%. When a function affecting primary production (PP) is calculated by Ecosim to minimize the sum of squares of the time series, a further 28% of variability is explained. The best fit is obtained by using the fishing mortality time series and by searching for the best combination of v parameters and the PP function simultaneously, accounting for 69% of total variability in the time series. The PP function obtained from the best fit significantly correlates with independent time series of an upwelling index (UI; rho = 0.47, p<0.05) and sea surface temperature (SST; rho = -0.45, p<0.05), representing environmental conditions in the study area during the same period of time. These results suggest that the SH ecosystem experienced at least two different environmentally distinct periods in the last three decades: (i) from 1970 to 1985 a relatively warm period with low levels of upwelling and PP, and (ii) from 1985 to 2004 a relatively cold period with increased upwelling and PP. This environmental variability can explain some of the changes in the food webs. Fishing (catch rate) and the environment (bottom-up anomaly in PP) appear to have affected the SH both at the stock and at the food web level between 1970 and 2004. The vulnerability setting indicates that the effects of external forcing factors may have been mediated by trophic controls operating in the food web.  
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  ISSN 0304-3800 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 330  
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Auteur Peraltilla, S.; Bertrand, S. url  doi
openurl 
  Titre In situ measurements of the speed of Peruvian anchovy schools Type Article scientifique
  Année 2014 Publication Revue Abrégée Fisheries Research  
  Volume 149 Numéro (up) Pages 92-94  
  Mots-Clés Multibeam sonar; Peruvian anchovy; School speed  
  Résumé While speed of fish schools is critical information for parameterizing numerous ecosystem models and evaluating fishery management options, it is poorly documented. Here we present results of in situ measurements of the speed of Peruvian anchovy schools, a small pelagic species that sustain the world's largest mono-specific fishery. Instantaneous school speed was in average 0.6 ms(-1), authorizing theoretical maximum displacements of similar to 26 km day(-1).  
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  ISSN 0165-7836 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 331  
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Auteur Torres-Irineo, E.; Gaertner, D.; Chassot, E.; Dreyfus-Leon, M. url  doi
openurl 
  Titre Changes in fishing power and fishing strategies driven by newtechnologies : the case of tropical tuna purse seiners in the easternAtlantic Ocean Type Article scientifique
  Année 2014 Publication Revue Abrégée Fisheries Research  
  Volume 155 Numéro (up) Pages 10-19  
  Mots-Clés  
  Résumé Technological advancements can influence both the fishing power of a fleet and the fishing strategies itemploys. To investigate these potential linkages, we examined almost three decades of data (1981&8211;2008)from French tropical tuna purse seiners operating in the eastern Atlantic Ocean. Applying a sequence ofstatistical methods at different temporal and spatial scales, we analyzed two indicators of fishing power(sets per boat-day on fish aggregating devices (FADs) and sets per boat-day on free-swimming schools)each of which represent a distinct fishing mode. Our results show that the increasing modernizationof this fleet has led to increases in both fishing power and the available number of fishing strategies tochoose from. A key output of this analysis was the breakdown of fishing power time series (for each fishingmode) into separate periods of continuous years during which catchability was assumed to be constant,thus identifying regime shifts. This partitioning allowed us to identify when key changes occurred inthe fishery. Changes in FAD-associated fishing were mostly driven by the introduction of radio beacons(early 1990s) which lead to an increase in fishing effort and an expansion of fishing grounds (directeffect) and the implementation of time-area management measures which resulted in a fragmentationof the traditional fishing grounds in the 2000s (indirect effect). During the same period, fishing on free-swimming schools also increased despite the biomass of stocks decreasing and fishing grounds remainingunchanged. This suggests these increases were driven by improvements in fish detection technology (e.g.,bird radars, sonar). These identified increases are not entirely unexpected: indeed it is widely recognizedthat fishing power in the purse seine tuna fishery has increased over time. However, these increases donot necessarily occur linearly. Thus, understanding how fishing power is changing over time (such asdetermining when regime shifts occur) is critical to improving the CPUE standardization procedure intropical tuna purse seine fisheries.  
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  Langue eng Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0165-7836 ISBN Médium  
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  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 335  
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Auteur Ashiq Ur Rahman, M.; Ajmal Khan, S.; Lyla, P.S.; Durand, J.-D. url  doi
openurl 
  Titre First record of Osteomugil perusii (Teleostei: Mugilidae) in Indian waters Type Article scientifique
  Année 2014 Publication Revue Abrégée Marine Biodiversity Records  
  Volume 7 Numéro (up) Pages null-null  
  Mots-Clés India; Indo-West Pacific; Kochi; Mugilidae; Parangipettai; long-finned mullet; record  
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  ISSN 1755-2672 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 594  
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