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Auteur Pethybridge, H.; BODIN, N.; Arsenault-Pernet, E.-J.; BOURDEIX, J.-H.; BRISSET, B.; BIGOT, J.-L.; ROOS, D.; Peter, M. url  openurl
  Titre (down) Temporal and inter-specific variations in forage fish feeding conditions in the NW Mediterranean: lipid content and fatty acid compositional changes Type Article scientifique
  Année 2014 Publication Revue Abrégée Marine Ecology Progress Series  
  Volume 512 Numéro Pages 39-54  
  Mots-Clés Clupeiformes; ecosystem health; Environmental variations; Nutritional condition; Prey Quality; Trophic markers  
  Résumé 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 partitioning and niche separation, as inferred from fatty acid profiles, were apparent between species. Sardine showed a more diverse, temporally separated feeding strategy than anchovy, and dietary overlap was higher in winter than summer with sardine having higher markers of copepods, 22:1n11 and 20:1n9. Sprat collected in winter occupied a separate niche area to both sardine and anchovy with higher total lipid content and carnivory biomarker 18:1n9. Our results show that the lipid dynamics of forage fishes can be used to gain quantitative insights into sub-system level changes in species interactions, including prey and predator productivity.  
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  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  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1129  
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Auteur Restrepo-Ortiz, C.X.; Auguet, J.C.; Casamayor, E.O. doi  openurl
  Titre (down) Targeting spatiotemporal dynamics of planktonic SAGMGC-1 and segregation of ammonia-oxidizing thaumarchaeota ecotypes by newly designed primers and quantitative polymerase chain reaction Type Article scientifique
  Année 2014 Publication Revue Abrégée Environmental Microbiology  
  Volume 16 Numéro 3 Pages 689-700  
  Mots-Clés  
  Résumé The annual dynamics of three different ammonia-oxidizing archaea (AOA) ecotypes (amoA gene) and of the SAGMGC-1 (Nitrosotalea-like aquatic Thaumarchaeota) group (16S rRNA gene) were studied by newly designed specific primers and quantitative polymerase chain reaction analysis in a deep oligotrophic high mountain lake (Lake Redon, Limnological Observatory of the Pyrenees, Spain). We observed segregated distributions of the main AOA populations, peaking separately in time and space, and under different ammonia concentrations and irradiance conditions. Strong positive correlation in gene abundances was found along the annual survey between 16S rRNA SAGMAGC-1 and one of the amoA ecotypes suggesting the potential for ammonia oxidation in the freshwater SAGMAGC-1 clade. We also observed dominance of Nitrosotalea-like ecotypes over Nitrosopumilus-like (Marine Group 1.1a) and not the same annual dynamics for the two thaumarchaeotal clades. The fine scale segregation in space and time of the different AOA ecotypes indicated the presence of phylogenetically close but ecologically segregated AOA species specifically adapted to specific environmental conditions. It remains to be elucidated what would be such environmental drivers.  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1313  
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Auteur Lefevre, S.; Domenici, P.; McKenzie, D.J. url  doi
openurl 
  Titre (down) Swimming in air-breathing fishes Type Article scientifique
  Année 2014 Publication Revue Abrégée Journal of Fish Biology  
  Volume 84 Numéro 3 Pages 661-681  
  Mots-Clés acid-base; aerobic metabolism; amia-calva; bimodal respiration; dicentrarchus-labrax; european sea-bass; exercise; exhaustive exercise; gar lepisosteus-platyrhincus; megalops-cyprinoides; pacific; partitioning; rainbow-trout; recovery; respiratory; tarpon; trout oncorhynchus-mykiss  
  Résumé Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0022-1112 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 877  
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Auteur Hancke, L.; Roberts, M.J.; Ternon, J.-F. url  doi
openurl 
  Titre (down) Surface drifter trajectories highlight flow pathways in the Mozambique Channel Type Article scientifique
  Année 2014 Publication Revue Abrégée Deep-Sea Research Part II.Topical Studies in Oceanography  
  Volume 100 Numéro No spécial Pages 27-37  
  Mots-Clés Frontal flow; Mesoscale eddies; Mozambique Channel; Surface circulation; Surface drifters  
  Résumé The pattern of surface circulation in the Mozambique Channel was elucidated from the trajectories of 82 satellite-tracked drifters over the period 2000-2010 and complementary satellite-derived altimetry. Overall, the trajectories indicated that anticyclonic activity was mostly observed on the western side of the Channel, with cyclonic activity being more prevalent in the east. A lack of eddy activity was noted in the southeast corner of the Channel (i.e. SW of Madagascar). Drifter behaviour illustrated that surface water from the Comoros Basin, entrained into anticyclonic eddies during formation, can be retained and isolated for months whilst being transported southwards through the Channel. During a tropical cyclone weather event, a drifter was observed to switch between counter-rotating eddies indicating that horizontal mixing of the Ekman layer does occur. The drifters also illustrated and emphasised the flow field and transport between eddies (i.e. the interstitial flow) in the Mozambique Channel. Despite the dominance of southward propagating anticyclones, drifters were able to move north and south through the Channel in the frontal flow field between eddies within periods of 51-207 days. Cross-channel transport in both directions between the Madagascan and Mozambique shelf regions was similarly observed, with time spans of 19-30 days. Surprisingly, drifters from the southern limb of the East Madagascar Current were transported westward across the channel to the Mozambique shelf. This transport was similarly facilitated by the frontal flow field between eddies. It is hypothesised that the frontal zones between eddies and interstitial waters play an important role in distributing biota in the Mozambique Channel.  
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  Editeur Lieu de Publication Éditeur Barlow, R.; Marsac, F.; Ternon, J.-F.; Roberts, M.  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0967-0645 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 361  
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Auteur Gimenez, O.; Buckland, S.T.; Morgan, B.J.T.; Bez, N.; Bertrand, S.; Choquet, R.; Dray, S.; Etienne, M.-P.; Fewster, R.; Gosselin, F.; Mérigot, B.; Monestiez, P.; Morales, J.M.; Mortier, F.; Munoz, F.; Ovaskainen, O.; Pavoine, S.; Pradel, R.; Schurr, F.M.; Thomas, L.; Thuiller, W.; Trenkel, V.; Valpine, P. de; Rexstad, E. url  doi
openurl 
  Titre (down) Statistical ecology comes of age Type Article scientifique
  Année 2014 Publication Revue Abrégée Biology Letters  
  Volume 10 Numéro 12 Pages 20140698  
  Mots-Clés  
  Résumé The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1–4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data.  
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  Volume de collection Numéro de collection Edition  
  ISSN 1744-9561, 1744-957x ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1213  
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