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Auteur (up) Heymans, J.J.; Coll, M.; Link, J.S.; Mackinson, S.; Steenbeek, J.; Walters, C.; Christensen, V. doi  openurl
  Titre Best practice in Ecopath with Ecosim food-web models for ecosystem-based management Type Article scientifique
  Année 2016 Publication Revue Abrégée Ecol. Model.  
  Volume 331 Numéro Pages 173-184  
  Mots-Clés benguela ecosystem; dynamics; Ecological network analysis; Ecopath with Ecosim; Ecosystem-based management; Ecosystem modelling; exploited ecosystems; impacts; indicators; marine ecosystems; Monte Carlo; network analysis; nw mediterranean sea; shelf ecosystem; southern benguela; Time series fitting  
  Résumé Ecopath with Ecosim (EwE) models are easier to construct and use compared to most other ecosystem modelling techniques and are therefore more widely used by more scientists and managers. This, however, creates a problem with quality assurance; to address this we provide an overview of best practices for creating Ecopath, models. We describe the diagnostics that can be used to check for thermodynamic and ecological principles, and highlight principles that should be used for balancing a model. We then highlight the pitfalls when comparing Ecopath models using Ecological Network Analysis indices. For dynamic simulations in Ecosim we show the state of the art in calibrating the model by fitting it to time series using a formal fitting procedure and statistical goodness of fit. Finally, we show how Monte Carlo simulations can be used to address uncertainty in input parameters, and we discuss the use of models in a management context, specifically using the concept of 'key runs' for ecosystem-based management. This novel list of best practices for EwE models will enable ecosystem managers to evaluate the goodness of fit of the given EwE model to the ecosystem management question. (C) 2016 The Authors. Published by Elsevier B.V.  
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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 0304-3800 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1644  
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Auteur (up) Jaquemet, S.; Ternon, J.-F.; Kaehler, S.; Thiebot, J.B.; Dyer, B.; Bemanaja, E.; Marteau, C.; Le Corre, M. url  doi
openurl 
  Titre Contrasted structuring effects of mesoscale features on the seabird community 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 200-211  
  Mots-Clés Foraging habitats; Frigatebird; Marine productivity; Mesoscale eddies; Red-footed booby; Sooty tern; Tropical marine predators; Tuna; Western Indian Ocean  
  Résumé The Mozambique Channel (western Indian Ocean) is a dynamic environment characterised by strong mesoscale features, which influence all biological components of the pelagic ecosystem. We investigated the distribution, abundance and feeding behaviour of seabirds in the Mozambique Channel in relation to physical and biological environmental variables, with a specific interest in mesoscale features. Seabird censuses were conducted in summer and winter during 7 cruises in the southern and northern Mozambique Channel. Tropical species accounted for 49% of the 37 species identified and 97% of the individuals, and species from the sub-Antarctic region constituted 30% of the identifications. The typically tropical sooty tern (Onychoprion fuscata) was the dominant species during all cruises, and overall accounted for 74% of the species observations and 85% of counted birds. Outputs of Generalised Linear Models at the scale of the Mozambique Channel suggested that higher densities of flying and feeding birds occurred in areas with lower sea surface temperatures and lower surface chlorophyll a concentrations. Most of the flocks of feeding birds did not associate with surface schools of fish or marine mammals, but when they did, these flocks were larger, especially when associated with tuna. While tropical species seemed to favour cyclonic eddies, frontal and divergence zones, non-tropical species were more frequently recorded over shelf waters. Sooty terns foraged preferentially in cyclonic eddies where zooplankton, micronelcton and tuna schools were abundant. Among other major tropical species, frigatebirds (Fregata spp.) predominated in frontal zones between eddies, where tuna schools also frequently occurred and where geostrophic currents were the strongest. Red-footed boobies (Sula sub) concentrated in divergence zones characterised by low sea level anomalies, low geostrophic currents, and high zooplanlcton biomass close to the surface. Our results highlight the importance of mescoscale features in structuring the tropical seabird community in the Mozambique Channel, in addition to segregating tropical and non-tropical species. The mechanisms underlying the segregation of tropical seabirds seem to partially differ from that of other tropical regions, and this may be a consequence of the strong local mesoscale activity, affecting prey size and availability schemes. Beyond characterising the foraging habitats of the seabird community of the Mozambique Channel, this study highlights the importance of this region as a hot spot for seabirds; especially the southern part, where several endangered sub-Antarctic species over-winter.  
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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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  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 363  
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Auteur (up) Jaspers, C.; Huwer, B.; Antajan, E.; Hosia, A.; Hinrichsen, H.-H.; Biastoch, A.; Angel, D.; Asmus, R.; Augustin, C.; Bagheri, S.; Beggs, S.E.; Balsby, T.J.S.; Boersma, M.; Bonnet, D.; Christensen, J.T.; Daenhardt, A.; Delpy, F.; Falkenhaug, T.; Finenko, G.; Fleming, N.E.C.; Fuentes, V.; Galil, B.; Gittenberger, A.; Griffin, D.C.; Haslob, H.; Javidpour, J.; Kamburska, L.; Kube, S.; Langenberg, V.T.; Lehtiniemi, M.; Lombard, F.; Malzahn, A.; Marambio, M.; Mihneva, V.; Moller, L.F.; Niermann, U.; Okyar, M.I.; Ozdemir, Z.B.; Pitois, S.; Reusch, T.B.H.; Robbens, J.; Stefanova, K.; Thibault, D.; van der Veer, H.W.; Vansteenbrugge, L.; van Walraven, L.; Wozniczka, A. doi  openurl
  Titre Ocean current connectivity propelling the secondary spread of a marine invasive comb jelly across western Eurasia Type Article scientifique
  Année 2018 Publication Revue Abrégée Glob. Ecol. Biogeogr.  
  Volume 27 Numéro 7 Pages 814-827  
  Mots-Clés abundance; biodiversity; biological invasions; black-sea; caspian sea; consequences; ctenophore mnemiopsis-leidyi; gelatinous zooplankton; invasion corridors; invasive species; jellyfish; larval transport; marine connectivity; Mnemiopsis leidyi; north-sea; range expansion; source populations; source-sink dynamics; waters; zooplankton  
  Résumé Aim: Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further distribution after the initial establishment of non-native species remain largely unresolved, especially in marine systems. Ocean currents can be a major driver governing range occupancy, but this has not been accounted for in most invasion ecology studies so far. We investigate how well initial establishment areas are interconnected to later occupancy regions to test for the potential role of ocean currents driving secondary spread dynamics in order to infer invasion corridors and the source-sink dynamics of a non-native holoplanktonic biological probe species on a continental scale. Location: Western Eurasia. Time period: 1980s-2016. Major taxa studied: 'Comb jelly' Mnemiopsis leidyi. Methods: Based on 12,400 geo-referenced occurrence data, we reconstruct the invasion history of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the temporal and spatial spread dynamics with large-scale connectivity patterns via ocean currents. Additionally, genetic markers are used to test the predicted connectivity between subpopulations. Results: Ocean currents can explain secondary spread dynamics, matching observed range expansions and the timing of first occurrence of our holoplanktonic non-native biological probe species, leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year-round populations in highly interconnected regions can re-seed genotypes over large distances after local extinctions. Main conclusions: Although the release of ballast water from container ships may contribute to the dispersal of non-native species, our results highlight the importance of ocean currents driving secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for secondary spread dynamics on a continental scale. Invasion risk assessments should consider large-scale connectivity patterns and the potential source regions of non-native marine species.  
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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 1466-822x ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2390  
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Auteur (up) Jensen, M.P.; FitzSimmons, N.N.; Bourjea, J.; Hamabata, T.; Reece, J.; Dutton, P.H. url  doi
openurl 
  Titre The evolutionary history and global phylogeography of the green turtle (Chelonia mydas) Type Article scientifique
  Année 2019 Publication Revue Abrégée Journal of Biogeography  
  Volume 46 Numéro 5 Pages 860-870  
  Mots-Clés marine; mtDNA; conservation units; genetic hotspots; genetic structure; sea turtle  
  Résumé Aim To examine the genetic structure and global phylogeography of the endangered green sea turtle, Chelonia mydas, in light of past climatic events and current conservation needs. Location Tropical and subtropical beaches around the world. Methods We analysed 386 base pairs of the mitochondrial (mt)DNA control region of 4,878 individual nesting green turtle samples from 127 rookeries globally. We used phylogeographic analysis to assess how demographic history, dispersal and barriers to gene flow have led to the current distribution of mtDNA lineages. Results We identified 11 divergent lineages that were tied to specific biogeographical regions. The phylogenetic analyses revealed an ancient origin for the species centred in the Indo-Pacific and more recent colonization of the Central/Eastern Pacific as well as the Atlantic Basin. Overall the phylogeographic structure was strong but with a clear pattern of regional connectivity among rookeries. A Large genetic separation was found where there were obvious barriers to dispersal such as between the Atlantic and Pacific oceans and across the Pacific Ocean, as well as less obvious barriers to dispersal. Admixture of mtDNA haplotype lineages was detected at latitudinal extremes across the Indian Ocean and western Pacific Ocean resulting in these areas being nucleotide diversity hotspots. The highest regional genetic diversity and high endemic richness was observed in the SW Pacific, NW Pacific, SW Indian and NW Indian oceans. Main conclusions Past climatic fluctuations greatly affected the distribution of genetic diversity in the highly migratory green turtle. Our data suggest that past climatic events influenced local populations in different ways and the species appears to have survived the last glaciations in multiple glacial refugia.  
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  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1365-2699 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000471344900003 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2608  
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Auteur (up) Jimenez, H.; Dumas, P.; Mouillot, D.; Bigot, L.; Ferraris, J. url  doi
openurl 
  Titre Harvesting effects on functional structure and composition of tropical invertebrate assemblages Type Article scientifique
  Année 2016 Publication Revue Abrégée ICES J. Mar. Sci.  
  Volume 73 Numéro 2 Pages 420-428  
  Mots-Clés Bta; marine protected areas; shellfishing; species composition; tropical benthos  
  Résumé Anthropogenic disturbances affect ecosystem structure and functioning. The quantification of their impacts on highly diverse and structurally complex ecosystems, such as coral reefs, is challenging. These communities are facing rising fishing pressure, particularly on Pacific Islands such as New Caledonia. The main objective was to quantify harvesting effects on invertebrate assemblages across two contrasting habitats (soft- and hard-bottom), by comparing communities in marine protected areas (MPAs) with non-MPAs using 10 biological and ecological traits. Patterns of trait composition were compared with those of species composition by non-metric multidimensional scaling and permutational analysis of variance analyses. Traits most responsible for differences between MPAs and non-MPAs were determined using SIMPER analysis, and predictions on shellfishing effects were discussed. A total of 248 species were recorded in hard-bottom communities, mainly characterized by mobile epifauna living on corals, crawling, and possessing a shell (molluscs) or a cuticle (crabs and echinoderms). Soft-bottom habitats contained 166 species, dominated by burrowing and sedentary species, especially shelled (largely bivalves) and worm-like organisms. Clear differences in species and trait composition between MPA and non-MPAs were highlighted in both habitats. Harvesting activities have community-wide effects that change the functional composition of invertebrate assemblages, in particular in terms of living habits and mobility. The observed shifts in benthic communities can affect the functioning of tropical coastal ecosystems and need to be included in small-scale fisheries management in poorly known tropical environments.  
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  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1054-3139, 1095-9289 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1535  
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