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Auteur (up) Fu, C.; Travers-Trolet, M.; Velez, L.; Grüss, A.; Bundy, A.; Shannon, L.J.; Fulton, E.A.; Akoglu, E.; Houle, J.E.; Coll, M.; Verley, P.; Heymans, J.J.; John, E.; Shin, Y.-J. url  doi
openurl 
  Titre Risky business: The combined effects of fishing and changes in primary productivity on fish communities Type Article scientifique
  Année 2018 Publication Revue Abrégée Ecological Modelling  
  Volume 368 Numéro Pages 265-276  
  Mots-Clés Combined effect; Fishing; Marine ecosystem; Meta-analysis; Multiple drivers; Synergism  
  Résumé There is an increasing need to understand community-level or whole-ecosystem responses to multiple stressors since the impacts of multiple stressors on marine systems depend not only on species-level responses, but also on species interactions and ecosystem structure. In this study, we used a multi-model ecosystem simulation approach to explore the combined effects of fishing and primary productivity on different components of the food-web across a suite of ecosystems and a range of model types. Simulations were carried out under different levels of primary productivity and various fishing scenarios (targeting different trophic levels). Previous work exploring the effects of multiple stressors often assumed that the combined effects of stressors are additive, synergistic or antagonistic. In this study, we included a fourth category “dampened”, which refers to less negative or to less positive impacts on a given ecosystem component compared to additive effects, and in contrast to previous studies, we explicitly considered the direction of the combined effects (positive or negative). We focused on two specific combined effects (negative synergism and positive dampened) associated with the ecological risk of resultant lower fish biomass than expected under additive effects. Through a meta-analysis of the multi-models’ simulation results, we found that (i) the risk of negative synergism was generally higher for low-trophic-level (LTL) taxa, implying that following an increase of fishing pressure on a given LTL stock, the subsequent decrease of biomass under low primary productivity would be higher than expected when fishing is the sole driver and (ii) the risk of positive dampened effects was generally higher for high-trophic-level (HTL) taxa, implying that given a management measure aimed at reducing the impact of fishing on HTL stocks, the subsequent rebuilding of these stocks would be slower than expected if only fishing were considered. Our approach to categorizing and exploring cumulative risk can be applied to evaluate other community properties and indicators and our findings could provide guidance in fisheries management.  
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  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 0304-3800 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2235  
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Auteur (up) Fu, C.; Xu, Y.; Bundy, A.; Grüss, A.; Coll, M.; Heymans, J.J.; Fulton, E.A.; Shannon, L.; Halouani, G.; Velez, L.; Akoğlu, E.; Lynam, C.P.; Shin, Y.-J. url  doi
openurl 
  Titre Making ecological indicators management ready: Assessing the specificity, sensitivity, and threshold response of ecological indicators Type Article scientifique
  Année 2019 Publication Revue Abrégée Ecological Indicators  
  Volume 105 Numéro Pages 16-28  
  Mots-Clés Ecological modelling; Fishing pressure; Gradient forest method; Indictor performance; Marine ecosystem; Primary productivity  
  Résumé Moving toward ecosystem-based fisheries management (EBFM) necessitates a suite of ecological indicators that are responsive to fishing pressure, capable of tracking changes in the state of marine ecosystems, and related to management objectives. In this study, we employed the gradient forest method to assess the performance of 14 key ecological indicators in terms of specificity, sensitivity and the detection of thresholds for EBFM across ten marine ecosystems using four modelling frameworks (Ecopath with Ecosim, OSMOSE, Atlantis, and a multi-species size-spectrum model). Across seven of the ten ecosystems, high specificity to fishing pressure was found for most of the 14 indicators. The indicators biomass to fisheries catch ratio (B/C), mean lifespan and trophic level of fish community were found to have wide utility for evaluating fishing impacts. The biomass indicators, which have been identified as Essential Ocean Variables by the Global Ocean Observing System (GOOS), had lower performance for evaluating fishing impacts, yet they were most sensitive to changes in primary productivity. The indicator B/C was most sensitive to low levels of fishing pressure with a generally consistent threshold response around 0.4*FMSY (fishing mortality rate at maximum sustainable yield) across nine of the ten ecosystems. Over 50% of the 14 indicators had threshold responses at, or below ∼0.6* FMSY for most ecosystems, indicating that these ecosystems would have already crossed a threshold for most indicators when fished at FMSY. This research provides useful insights on the performance of indicators, which contribute to facilitating the worldwide move toward EBFM.  
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  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 1470-160x ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000490574200003 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2579  
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Auteur (up) Gaboriau, T.; Leprieur, F.; Mouillot, D.; Hubert, N. doi  openurl
  Titre Influence of the geography of speciation on current patterns of coral reef fish biodiversity across the Indo-Pacific Type Article scientifique
  Année 2018 Publication Revue Abrégée Ecography  
  Volume 41 Numéro 8 Pages 1295-1306  
  Mots-Clés damselfishes pomacentridae; evolutionary history; family labridae; global patterns; marine biodiversity; maximum-likelihood; peripheral endemism; phylogenies; species richness; west pacific  
  Résumé The role of speciation processes in shaping current biodiversity patterns represents a major scientific question for ecologists and biogeographers. Hence, numerous methods have been developed to determine the geography of speciation based on co-occurrence between sister-species. Most of these methods rely on the correlation between divergence time and several metrics based on the geographic ranges of sister-taxa (i.e. overlap, asymmetry). The relationship between divergence time and these metrics has scarcely been examined in a spatial context beyond regression curves. Mapping this relationship across spatial grids, however, may unravel how speciation processes have shaped current biodiversity patterns through space and time. This can be particularly relevant for coral reef fishes of the Indo-Pacific since the origin of the exceptional concentration of biodiversity in the Indo-Australian Archipelago (IAA) has been actively debated, with several alternative hypotheses involving species diversification and dispersal. We reconstructed the phylogenetic relationships between three species-rich families of coral reef fish (Chaetodontidae, Labridae, Pomacentridae) and calculated co-occurrence metrics between closely related lineages of those families. We demonstrated that repeated biogeographic processes can be identified in present-day species distribution by projecting co-occurrence metrics between related lineages in a geographical context. Our study also evidence that sister-species do not co-occur randomly across the Indo-Pacific, but tend to overlap their range within the IAA. We identified the imprint of two important biogeographic processes that caused this pattern in 48% of the sister-taxa considered: speciation events within the IAA and repeated divergence between the Indian and Pacific Ocean, with subsequent secondary contact in the IAA.  
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  Auteur institutionnel Thèse  
  Editeur Lieu de Publication Éditeur  
  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 0906-7590 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2388  
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Auteur (up) GAGNAIRE, P.-A.; BROQUET, T.; AURELLE, D.; VIARD, F.; SOUISSI, A.; BONHOMME, F.; ARNAUD-HAOND, S.; Bierne, N. url  doi
openurl 
  Titre Using neutral, selected, and hitchhiker loci to assess connectivity of marine populations in the genomic era Type Article scientifique
  Année 2015 Publication Revue Abrégée Evolutionary Applications  
  Volume 8 Numéro 8 Pages 769-786  
  Mots-Clés connectivity; gene flow; marine conservation; population genomics; Population structure  
  Résumé Estimating the rate of exchange of individuals among populations is a central concern to evolutionary ecology and its applications to conservation and management. For instance, the efficiency of protected areas in sustaining locally endangered populations and ecosystems depends on reserve network connectivity. The population genetics theory offers a powerful framework for estimating dispersal distances and migration rates from molecular data. In the marine realm, however, decades of molecular studies have met limited success in inferring genetic connectivity, due to the frequent lack of spatial genetic structure in species exhibiting high fecundity and dispersal capabilities. This is especially true within biogeographic regions bounded by well-known hotspots of genetic differentiation. Here, we provide an overview of the current methods for estimating genetic connectivity using molecular markers and propose several directions for improving existing approaches using large population genomic datasets. We highlight several issues that limit the effectiveness of methods based on neutral markers when there is virtually no genetic differentiation among samples. We then focus on alternative methods based on markers influenced by selection. Although some of these methodologies are still underexplored, our aim was to stimulate new research to test how broadly they are applicable to nonmodel marine species. We argue that the increased ability to apply the concepts of cline analyses will improve dispersal inferences across physical and ecological barriers that reduce connectivity locally. We finally present how neutral markers hitchhiking with selected loci can also provide information about connectivity patterns within apparently well-mixed biogeographic regions. We contend that one of the most promising applications of population genomics is the use of outlier loci to delineate relevant conservation units and related eco-geographic features across which connectivity can be measured.  
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  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 1752-4571 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1434  
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Auteur (up) Garavelli, L.; Colas, F.; Verley, P.; Kaplan, D.M.; Yannicelli, B.; Lett, C. url  doi
openurl 
  Titre Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile Type Article scientifique
  Année 2016 Publication Revue Abrégée Plos One  
  Volume 11 Numéro 1 Pages e0146418  
  Mots-Clés Biological transport; Biophysics; Chile (country); Death rates; Fecundity; Hydrodynamics; Larvae; Marine biology  
  Résumé In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future.  
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  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 1932-6203 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1534  
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