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Auteur (up) Potier, M.; Ménard, F.; Benivary, H.D.; Sabatié, R. url  doi
openurl 
  Titre Lenght and weight estimates from diagnostic hard part structures of fish, crustacea and cephalopods forage species in the western Indian Ocean Type Article scientifique
  Année 2011 Publication Revue Abrégée Environmental Biology of Fishes  
  Volume Numéro Pages  
  Mots-Clés Analyse Quantitative; Contenu Stomacal; Espece Pelagique; Poisson Marin; predation; Relation Taille Poids; Structure Trophique  
  Résumé  
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  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1573-5133 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 159  
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Auteur (up) Queiros, Q.; Fromentin, J.-M.; Astruc, G.; Bauer, R.K.; Saraux, C. doi  openurl
  Titre Dolphin predation pressure on pelagic and demersal fish in the northwestern Mediterranean Sea Type Article scientifique
  Année 2018 Publication Revue Abrégée Mar. Ecol.-Prog. Ser.  
  Volume 603 Numéro Pages 13-27  
  Mots-Clés Anchovy; artisanal fisheries; bottle-nosed dolphins; Bottlenose dolphin; cetaceans reveals; delphinus-delphis; European hake; Gulf of Lions; longline fisheries; marine ecosystem; Predation pressure; Sardine; stenella-coeruleoalba; Striped dolphin; striped-dolphin; Top-down effect; trophic cascades; tursiops-truncatus  
  Résumé Sardine Sardina pilchardus, anchovy Engraulis encrasicolus and European hake Merluccius merluccius represent a significant part of the commercial landings in the Gulf of Lions (northwestern Mediterranean Sea). However, their stocks have shown severe declines during the last decades due to fishing pressure and/or environmental changes. The aim of this study was to estimate the current predation pressure of bottlenose dolphins Tursiops truncatus and striped dolphins Stenella coeruleoalba – which are abundant in the area-on sardine, anchovy and hake. To do so, we developed an original approach based on several data sets and models (aerial surveys, stomach contents, allometric and stock assessment models) and Monte Carlo simulations to incorporate various sources of uncertainty due to data limitations. Despite the uncertainties, the results showed that dolphin predation pressure on sardine and anchovy was extremely low in the Gulf of Lions (all simulations <0.5 % of the available stock), indicating little impact of dolphins on those populations. However, significant predation pressure on hake (median value: 23 %) was detected, a value which might have doubled in the last 30 yr because of hake overfishing. Overexploitation has thus reinforced the natural mortality of hake due to dolphin predation, but this predation pressure remains 2 to 3 times lower than that exerted by fisheries.  
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  Langue English 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 @ alain.herve @ collection 2429  
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Auteur (up) Ramirez-Romero, E.; Molinero, J.C.; Paulsen, M.; Javidpour, J.; Clemmesen, C.; Sommer, U. doi  openurl
  Titre Quantifying top-down control and ecological traits of the scyphozoan Aurelia aurita through a dynamic plankton model Type Article scientifique
  Année 2018 Publication Revue Abrégée J. Plankton Res.  
  Volume 40 Numéro 6 Pages 678-692  
  Mots-Clés 2 hydromedusae; annual cycle; baltic sea; coastal ecosystem; common jellyfish; ctenophore mnemiopsis-leidyi; jellyfish; kiel-bight; planktonic food web; population modeling; population-dynamics; predation impact; sarsia-tubulosa; stage-resolved model; zooplankton  
  Résumé Aurelia aurita (Linneaus, 1758) is a cosmopolitan scyphozoan, probably the most investigated jellyfish in temperate and highly productive coastal ecosystems. Despite a prominent top-down control in plankton food webs, a mechanistic understanding of A. aurita population dynamics and trophic interactions has been barely addressed. Here we develop a food web dynamic model to assess A. aurita role in the seasonal plankton dynamics of the Kiel Fjord, southwestern Baltic Sea. The model couples low trophic level dynamics, based on a classical Nutrient Phytoplankton Zooplankton Detritus (NPZD) model, to a stage-resolved copepod model (referencing Pseudocalanus sp.) and a jellyfish model (A. aurita ephyra and medusa) as consumers and predators, respectively. Simulations showed the relevance of high abundances of A. aurita, which appear related with warm winter temperatures, promoting a shift from a copepod-dominated food web to a ciliate and medusa dominated one. The model captured the intraspecific competition triggered by the medusae abundance and characterized by a negative relationship between population density and individual size/weight. Our results provide a mechanistic understanding of an emergent trait such as size shaping the food web functioning, driving predation rates and population dynamics of A. aurita, driving its sexual reproductive strategy at the end of the pelagic phase.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0142-7873 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2476  
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Auteur (up) Reynolds, P.L.; Stachowicz, J.J.; Hovel, K.; Bostrom, C.; Boyer, K.; Cusson, M.; Eklof, J.S.; Engel, F.G.; Engelen, A.H.; Eriksson, B.K.; Fodrie, F.J.; Griffin, J.N.; Hereu, C.M.; Hori, M.; Hanley, T.C.; Ivanov, M.; Jorgensen, P.; Kruschel, C.; Lee, K.-S.; McGlathery, K.; Moksnes, P.-O.; Nakaoka, M.; O'Connor, M.I.; O'Connor, N.E.; Orth, R.J.; Rossi, F.; Ruesink, J.; Sotka, E.E.; Thormar, J.; Tomas, F.; Unsworth, R.K.F.; Whalen, M.A.; Duffy, J.E. doi  openurl
  Titre Latitude, temperature, and habitat complexity predict predation pressure in eelgrass beds across the Northern Hemisphere Type Article scientifique
  Année 2018 Publication Revue Abrégée Ecology  
  Volume 99 Numéro 1 Pages 29-35  
  Mots-Clés patterns; communities; diversity; ecosystems; temperature; seagrasses; eutrophication; predation; biogeography; prey; top-down control; enrichment; latitude; mesograzer; seagrass; species interactions; water temperature; Zostera  
  Résumé Latitudinal gradients in species interactions are widely cited as potential causes or consequences of global patterns of biodiversity. However, mechanistic studies documenting changes in interactions across broad geographic ranges are limited. We surveyed predation intensity on common prey (live amphipods and gastropods) in communities of eelgrass (Zostera marina) at 48 sites across its Northern Hemisphere range, encompassing over 37 degrees of latitude and four continental coastlines. Predation on amphipods declined with latitude on all coasts but declined more strongly along western ocean margins where temperature gradients are steeper. Whereas insitu water temperature at the time of the experiments was uncorrelated with predation, mean annual temperature strongly positively predicted predation, suggesting a more complex mechanism than simply increased metabolic activity at the time of predation. This large-scale biogeographic pattern was modified by local habitat characteristics; predation declined with higher shoot density both among and within sites. Predation rates on gastropods, by contrast, were uniformly low and varied little among sites. The high replication and geographic extent of our study not only provides additional evidence to support biogeographic variation in predation intensity, but also insight into the mechanisms that relate temperature and biogeographic gradients in species interactions.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0012-9658 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2254  
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Auteur (up) Travers, M.; Shin, Y.-J.; Jennings, S.; Machu, E.; Huggett, J.A.; Field, J.G.; Cury, P. url  doi
openurl 
  Titre Two-way coupling versus one-way forcing of plankton and fish models to predict ecosystem changes in the Benguela Type Article scientifique
  Année 2009 Publication Revue Abrégée Ecological Modelling  
  Volume 220 Numéro 21 Pages 3089-3099  
  Mots-Clés Benguela upwelling; Ecem 07; End-to-end approach; food web; marine; Marine ecosystem model coupling; Predation  
  Résumé 'End-to-end' models have been adopted in an attempt to capture more of the processes that influence the ecology of marine ecosystems and to make system wide predictions of the effects of fishing and climate change. Here, we develop an end-to-end model by coupling existing models that describe the dynamics of low (ROMS-N(2)P(2)Z(2)D(2)) and high trophic levels(OSMOSE). ROMS-N(2)P(2)Z(2)D(2) is a biogeochemical model representing phytoplankton and zooplankton seasonal dynamics forced by hydrodynamics in the Benguela upwelling ecosystem. OSMOSE is an individual-based model representing the dynamics of several species of fish, linked through opportunistic and size-based trophic interactions. The models are coupled through a two-way size-based predation process. Plankton provides prey for fish, and the effects of predation by fish on the plankton are described by a plankton mortality term that is variable in space and time. Using the end-to-end model, we compare the effects of two-way coupling versus one-way forcing of the fish model with the plankton biomass field. The fish-induced mortality on plankton is temporally variable, in part explained by seasonal changes in fish biomass. Inclusion of two-way feedback affects the seasonal dynamics of plankton groups and usually reduces the amplitude of variation in abundance (top-down effect). Forcing and coupling lead to different predicted food web structures owing to changes in the dominant food chain which is supported by plankton (bottom-up effect). Our comparisons of one-way forcing and two-way coupling show how feedbacks may affect abundance, food web structure and food web function and emphasise the need to critically examine the consequences of different model architectures when seeking to predict the effects of fishing and climate change.  
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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 0304-3800 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 29  
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