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Auteur Alfonso, S.; Sadoul, B.; Gesto, M.; Joassard, L.; Chatain, B.; Geffroy, B.; Bégout, M.-L. url  doi
openurl 
  Titre Coping styles in European sea bass: The link between boldness, stress response and neurogenesis Type Article scientifique
  Année 2019 Publication Revue Abrégée Physiology & Behavior  
  Volume 207 Numéro Pages 76-85  
  Mots-Clés Gene transcription; HPI axis; Neurotransmitters; Personality  
  Résumé Coping styles consist of a coherent set of individual physiological and behavioral differences in stress responses that are consistent across time and context. Such consistent inter-individual differences in behavior have already been shown in European sea bass (Dicentrarchus labrax), but the associated mechanisms are still poorly understood. Here, we combine physiological measurements with individual behavioral responses in order to characterize coping styles in fish. Fish were tagged and placed in a tank for group risk-taking tests (GRT) at 8 months of age to evaluate boldness using the proxy latency of leaving a sheltered area towards an open area. A subsample of these fish were individually challenged 16 months later using an open field test (OFT), in which the boldness was assessed after being placed in a shelter within an open arena. Latency to exit the shelter, time spent in the shelter, and distance travelled were recorded for this purpose. The blood and brain were then collected to evaluate plasma cortisol concentration and neurotransmitter levels (dopamine, norepinephrine, serotonin, and related metabolites), as well as brain transcription of key genes involved in stress axis regulation (gr1, gr2, mr, crf), neurogenesis (neurod1, neurod2, pcna), and neuronal development (egr1). Fish acting bolder in the GRT were not necessarily those acting bolder in the OFT, highlighting the relatively low consistency across different types of tests performed with a 16-months interval. There was, however, a significant correlation between stress markers and boldness. Indeed, mRNA levels of mr, crf, gr2, egr1, and neurod2, as well as norepinephrine levels were higher in shy than bold fish, whereas brain serotonergic activity was lower in shy fish. Overall, our study highlights the fact that boldness was not consistent over time when testing context differed (group vs. alone). This is in agreement with previous literature suggesting that social context play a key role in boldness measurement and that the particular life history of each individual may account in shaping the personality fate of a fish.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0031-9384 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2575  
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Auteur Diaz, F.; Bănaru, D.; Verley, P.; Shin, Y.-J. url  doi
openurl 
  Titre Implementation of an end-to-end model of the Gulf of Lions ecosystem (NW Mediterranean Sea). II. Investigating the effects of high trophic levels on nutrients and plankton dynamics and associated feedbacks Type Article scientifique
  Année 2019 Publication Revue Abrégée Ecological Modelling  
  Volume 405 Numéro Pages 51-68  
  Mots-Clés End-to-end model; Fisheries; Food web functioning; Plankton; Two-ways coupling  
  Résumé The end-to-end OSMOSE-GoL model parameterized, calibrated and evaluated for the Gulf of Lions ecosystem (Northwestern Mediterranean Sea) has been used to investigate the effects of introducing two-ways coupling between the dynamics of Low and High Trophic Level groups. The use of a fully dynamic two-ways coupling between the models of Low and High Trophic Levels organisms provided some insights in the functioning of the food web in the Gulf of Lions. On the whole microphytoplankton and mesozooplankton were found to be preyed upon by High Trophic Levels planktivorous groups at rates lower than 20% and 30% of their respective natural mortality rates, but these relatively low rates involved some important alterations in the infra-seasonal and annual cycles of both High and Low Trophic Levels groups. They induced significant changes in biomass, fisheries landings and food web interactions by cascading effects. Spatial differential impacts of High Trophic Levels predation on plankton are less clear except in areas in which primary productivity is high. Higher predation rates on plankton groups were encountered within the area of the Rhone river’s influence and in areas associated to the presence of mesoscale eddies in the Northwestern part of the Gulf of Lions, especially. Generally, the pressure of the High Trophic Levels predation was the highest in areas of highest biomass whatever the plankton group considered. The two-ways coupling between Low and High Trophic Levels models revealed both bottom-up and top-down controls in the ecosystem with effects on planktivorous species similar to those observed in the field. The use of the end-to-end model enabled to propose a set of potential mechanisms that may explain the observed decrease in small pelagic catches by the French Mediterranean artisanal fisheries over the last decade.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0304-3800 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2577  
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Auteur Drira, S.; Ben Rais Lasram, F.; Ben Rejeb Jenhani, A.; Shin, Y.J.; Guilhaumon, F. url  doi
openurl 
  Titre Species-area uncertainties impact the setting of habitat conservation targets and propagate across conservation solutions Type Article scientifique
  Année 2019 Publication Revue Abrégée Biological Conservation  
  Volume 235 Numéro Pages 279-289  
  Mots-Clés  
  Résumé Systematic Conservation Planning (SCP) is a widely-used approach to develop networks of protected areas. A crucial step in the SCP process is to set conservation targets for biodiversity features (explicit goals that quantify the minimum amount of each biodiversity feature to be covered by the protected areas). When the biodiversity features are different habitats occurring in the planning region, a relevant approach, based on the Species-Area Relationship (SAR), defines targets so as to maximize biodiversity representation within each habitat type. While many formulations of the SAR exist, their application remains dominated by the log-transformation of Power-law model. However, documented habitat-related and taxonomic idiosyncrasies in the shape of the SAR question the effectiveness of a given ubiquitous model in fitting data compared to others. Here, using 13 SAR functional forms, we investigate whether the habitat-related SAR uncertainties propagate across the entire conservation planning process and lead to both divergent conservation targets and conservation solutions for six habitats in the Mediterranean sea. Results revealed uncertainties in model selection across habitats, which leads to different SAR habitat-targets. Constraining a systemic conservation planning tool (Marxan) with those targets provided contrasted sets of priority areas for different SAR scenario. Our study demonstrated that restraining to one particular SAR model is inappropriate at fitting all SAR datasets, providing consequently conservation targets diverging markedly from data-driven SAR inferences. More importantly, corresponding reserve networks are either inefficient or overstated for the protection of habitats, leading to waste of scarce conservation resources that should be used sparingly. Therefore, we suggest to evaluate different SAR models and, when appropriate to carry out a multi-model inference to provide robust habitat-specific conservation targets.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0006-3207 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000472696400028 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2578  
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Auteur 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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  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 Lett, C.; Barrier, N.; Ourmières, Y.; Petit, C.; Labonne, M.; Bourjea, J.; Darnaude, A.M. url  doi
openurl 
  Titre Modeling larval dispersal for the gilthead seabream in the northwestern Mediterranean Sea Type Article scientifique
  Année 2019 Publication Revue Abrégée Marine Environmental Research  
  Volume Numéro Pages 104781  
  Mots-Clés Biophysical model; Connectivity; Fish; Gulf of Lions; Larvae; Models-hydrodynamic; Otolith  
  Résumé To investigate dispersal and connectivity between spawning and lagoon nursery habitats of the gilthead seabream, Sparus aurata, in the Gulf of Lions (northwestern Mediterranean Sea), we modeled the potential transport of the species’ larvae between its supposed main spawning site in the region (the Planier Island) and two of its main local nursery areas (the coastal lagoons of Thau and Salses-Leucate). Passive larval drift simulations using a dispersal biophysical model showed a large variability in the possible trajectories from spawning to nursery areas and in the predicted ages for larvae arrival on the two nursery sites. The most common ages at arrival obtained in the simulations (20–60 days) are broadly consistent with previous modeling studies but contrast with the actual ages of the S. aurata post-larvae collected in 2016 and 2017 at time of the lagoon entrances (60–90 days, from otolith readings). The period between 25 and 70 days being critical for gilthead seabream larvae to acquire sufficient swimming, osmoregulatory, and olfactory abilities to enter coastal lagoons, we argue that ontogenic development plays a crucial role in the transport and local retention of S. aurata larvae in the studied region, explaining the discrepancy between simulation results and observed data.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0141-1136 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2613  
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