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Auteur Ayata, S.-D.; Irisson, J.-O.; Aubert, A.; Berline, L.; Dutay, J.-C.; Mayot, N.; Nieblas, A.-E.; D'Ortenzio, F.; Palmiéri, J.; Reygondeau, G.; Rossi, V.; Guieu, C.
Titre Regionalisation of the Mediterranean basin, a MERMEX synthesis Type Article scientifique
Année 2018 Publication (down) Progress in Oceanography Revue Abrégée
Volume 163 Numéro Pages 7-20
Mots-Clés Mediterranean Sea; regionalisation; biogeochemistry; circulation; mesoscale features; epipelagic ocean; management; spatial planning
Résumé Regionalisation aims at delimiting provinces within which physical conditions, chemical properties, and biological communities are reasonably homogeneous. This article proposes a synthesis of the many recent regionalisations of the open-sea regions of the Mediterranean Sea. The nine studies considered here defined regions based on different, and sometimes complementary, criteria: dynamics of surface chlorophyll concentration, ocean currents, three-dimensional hydrological and biogeochemical properties, or the distribution of organisms. Although they identified different numbers and patterns of homogeneous regions, their compilation in the epipelagic zone identifies nine consensus frontiers, eleven consensus regions with relatively homogeneous conditions, and four heterogeneous regions with highly dynamical conditions. The consensus frontiers and regions are in agreement with well-known hydrodynamical features of the Mediterranean Sea, which constrain the distribution of hydrological and ecological variables. The heterogeneous regions are rather defined by intense mesoscale activity. The synthesis proposed here could constitute a reference step for management actions and spatial planning, such as the application of the European Marine Strategy Framework Directive, and for future biogeochemical and ecological studies in the Mediterranean Sea.
Adresse Center for Prototype Climate Modeling, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates
Auteur institutionnel Thèse
Editeur Elsevier BV Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0079-6611 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 51673 collection 2349
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Auteur DRUON, J.-N.; FROMENTIN, J.-M.; AULANIER, F.; HEIKKONEN, J.
Titre Potential feeding and spawning habitats of Atlantic bluefin tuna in the Mediterranean Sea Type Article scientifique
Année 2011 Publication (down) Marine Ecology-progress Series Revue Abrégée
Volume 439 Numéro Pages 223-240
Mots-Clés Habitat mapping; Bluefin tuna; Thunnus thynnus; Feeding; Spawning; Mediterranean Sea; Remote sensing; Satellite data
Résumé Atlantic bluefin tuna Thunnus thynnus (ABFT) is a fish of high market value which has recently become strongly overexploited, notably in the Mediterranean Sea. This area is an essential habitat for ABFT reproduction and growth. We present here an approach for deriving the daily mapping of potential ABFT feeding and spawning habitats based on satellite-derived sea surface temperature (SST) and chl a concentration. The feeding habitat was mainly derived from the simultaneous occurrence of oceanic fronts of temperature and chl a content while the spawning habitat was mostly inferred from the heating of surface waters. Generally, higher chl a contents were found to be preferred for the feeding habitat and a minimum SST value was found for the spawning habitat. Both habitats were defined by the presence of relevant oceanographic features and are therefore potential and functionally-linked habitats. This approach provides, for the first time, a synoptic view of the potential ABFT habitats in the Mediterranean Sea. The model performs well in areas where both satellite data and ABFT observations are available, as 80% of presence data are in the vicinity of potential habitats. The computed monthly, seasonal and annual maps of potential feeding and spawning habitat of ABFT from 2003 to 2009 are in good agreement with current knowledge on ABFT. Overall, the habitat size of ABFT is about 6% of the Mediterranean Sea surface. The results displayed a strong seasonality in habitat size and locations as well as high year-to-year variations (30 to 60%), particularly for the potential spawning habitat, which is key information for evaluating the utility of ABFT Marine Protected Areas in the Mediterranean Sea.
Adresse IFREMER, Ctr Rech Halieut Mediterraneen & Trop, F-34203 Sete, France.
Auteur institutionnel Thèse
Editeur Inter-research Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0171-8630 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 16053 collection 1003
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Auteur BROSSET, P.; MENARD, F.; FROMENTIN, J.-M.; BONHOMMEAU, S.; ULSES, C.; BOURDEIX, J.-H.; BIGOT, J.-L.; VAN BEVEREN, E.; ROOS, D.; SARAUX, C.
Titre Influence of environmental variability and age on the body condition of small pelagic fish in the Gulf of Lions Type Article scientifique
Année 2015 Publication (down) Marine Ecology Progress Series Revue Abrégée
Volume 529 Numéro Pages 219-231
Mots-Clés Anchovy; Sardine; Relative condition factor; NW Mediterranean Sea; Endogenous effect; Environmental effect
Résumé 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 years), sardines older than 1 yr appeared to be more strongly affected than younger individuals. Time-series were analyzed using generalized linear models (GLMs) to examine the effects of oceanographic abiotic (temperature, Western Mediterranean Oscillation [WeMO] and Rhone outflow) and biotic (chlorophyll a and 6 plankton classes) factors on fish condition. The selected models explained 48 and 35% of the variance of anchovy and sardine condition, respectively. Sardine condition was negatively related to temperature but positively related to the WeMO and mesozooplankton and diatom concentrations. A positive effect of mesozooplankton and Rhone runoff on anchovy condition was detected. The importance of increasing temperatures and reduced water mixing in the NW Mediterranean Sea, affecting planktonic productivity and thus fish condition by bottom-up control processes, was highlighted by these results. Changes in plankton quality, quantity and phenology could lead to insufficient or inadequate food supply for both species.
Adresse Univ Toulouse 3, CNRS, INSU, Lab Aerol,UMR 5560, F-31400 Toulouse, France.
Auteur institutionnel Thèse
Editeur Inter-research Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0171-8630 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 38334 collection 1231
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Auteur Le Bourg, B.; Bănaru, D.; Saraux, C.; Nowaczyk, A.; Le Luherne, E.; Jadaud, A.; Bigot, J.-L.; Richard, P.
Titre Trophic niche overlap of sprat and commercial small pelagic teleosts in the Gulf of Lions (NW Mediterranean Sea) Type Article scientifique
Année 2015 Publication (down) Journal of Sea Research Revue Abrégée
Volume Numéro Pages
Mots-Clés Anchovies; Sardines; Sprats; North-western Mediterranean sea; Stomach contents; Stable isotopes
Résumé 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 generalist feeders compared to anchovies and sardines. Ontogenetic changes as well as spatial and temporal variations of the diet occurred in the three species. Stable isotope analysis revealed mobility of sardines and sprats among feeding areas while anchovies exhibited preferred feeding areas. Sprats showed a higher relative condition assessed by C/N ratios than sardines and anchovies. Our results showed an overlap of the trophic niches for the three species, indicating a potential trophic competition in the Gulf of Lions.
Adresse Université de La Rochelle, UMR CNRS 7266 LIENSs, 2 Rue Olympe de Gouges, 17000 La Rochelle, France
Auteur institutionnel Thèse
Editeur Elsevier BV Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1385-1101 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 38314 collection 1232
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Auteur BROSSET, P.; FROMENTIN, J.-M.; MENARD, F.; PERNET, F.; BOURDEIX, J.-H.; BIGOT, J.-L.; VAN BEVEREN, E.; PEREZ RODIA, M.A.; CHOY, S.; SARAUX, C.
Titre Measurement and analysis of small pelagic fish condition: A suitable method for rapid evaluation in the field Type Article scientifique
Année 2015 Publication (down) Journal Of Experimental Marine Biology And Ecology Revue Abrégée
Volume 462 Numéro Pages 90-97
Mots-Clés Anchovy; Fatmeter; Lipids; Mediterranean Sea; Sardine; Sprat
Résumé 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 correlated quite well with the relative lipid contents of all species, regardless of the reproductive period (R2 = 0.69 for anchovy, R2 = 0.75 for sprat and R2 = 0.48 for sardine). Kn correlated more poorly with relative lipid content (R2 = 0.22 for anchovy and R2 = 0.41 for sardine, ns for sprat), especially during the reproductive period, pointing out the difficulty for such an index to precisely reflect changes in fat allocation. During the reproductive period, changes in Kn could reflect other processes, such as changes in protein content. Therefore, these different types of commonly used indices do not reflect exactly the same type of energy stores. The high repeatability of the fatmeter was brought to light, so that only one measurement on each fish side may be necessary to evaluate the relative lipid content of a small pelagic fish. Finally, fatmeter measurements were not affected by freezing storage up to one month for anchovy (R2 = 0.66) and sardine (R2 = 0.90), making it possible to use frozen samples of both commercial and scientific survey. In contrast, the freezing storage for sprat should be avoided. Based on this study, the Fatmeter appears to be a suitable indirect method to assess condition and fat content of sardine and anchovy on a large number of individuals.
Adresse IFREMER, Laboratoire des sciences de l'Environnement Marin, LEMAR, Technopole Brest Iroise, BP 70, 29280 Plouzané, France
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0022-0981 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 33741 collection 984
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