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Auteur Meistertzheim, A.-L.; Lartaud, F.; Arnaud-Haond, S.; Kalenitchenko, D.; Bessalam, M.; Le Bris, N.; Galand, P.E. url  doi
openurl 
  Titre Patterns of bacteria-host associations suggest different ecological strategies between two reef building cold-water coral species Type Article scientifique
  Année 2016 Publication Revue Abrégée Deep Sea Research Part I: Oceanographic Research Papers  
  Volume 114 Numéro Pages (up) 12-22  
  Mots-Clés Bacterial communities; Bacterial ecology; Deep-Sea corals; Lophelia pertusa; Madrepora oculata; Mediterranean Sea; Microbe-microbe and microbe-host interactions  
  Résumé Cold-water corals (CWC) are main ecosystem engineers of the deep sea, and their reefs constitute hot-spots of biodiversity. However, their ecology remains poorly understood, particularly, the nature of the holobiont formed by corals with their associated bacterial communities. Here, we analyzed Madrepora oculata and Lophelia pertusa samples, collected from one location in a Mediterranean canyon in two different seasons (autumn and spring), in order to test for species specificity and temporal stability of the host-bacteria associations. The 16S rRNA sequencing revealed host-specific patterns of bacterial communities associated with L. pertusa and M. oculata, both in terms of community composition and diversity. All analyzed M. oculata polyps exhibited temporally and spatially similar bacterial communities dominated by haplotypes homologous to the known cnidarians-associated genus Endozoicomonas. In contrast, the bacterial communities associated with L. pertusa varied among polyps from the same colony, as well as among distinct colonies and between seasons. While the resilient consortium formed by M. oculata and its bacterial community fit the definition of holobiont, the versatility of the L. pertusa microbiome suggests that this association is more influenced by the environmental conditions or nutritional status. Our results thus highlight distinct host/microbes association strategies for these two closely related Scleractinians sharing the same habitat, suggesting distinct sensitivity to environmental 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 0967-0637 ISBN Médium  
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  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1565  
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Auteur Boyd, C.; Punt, A.E.; Weimerskirch, H.; Bertrand, S. url  doi
openurl 
  Titre Movement models provide insights into variation in the foraging effort of central place foragers Type Article scientifique
  Année 2014 Publication Revue Abrégée Ecological Modelling  
  Volume 286 Numéro Pages (up) 13-25  
  Mots-Clés Animal movement; Foraging ecology; Hidden Markov model; Provisioning theory; Seabirds; Sula variegata  
  Résumé Ecology and conservation depend on an understanding of how animals adjust their behaviour patterns in response to changes in their environment. Central place foragers (CPFs) are well-suited for developing ecological models of adaptive processes because their objective functions and operational constraints can be reasonably inferred. Central place foraging and provisioning theory provide the theoretical framework for this analysis. Analysis of CPF time allocation and energy budgets can provide insights into their strategies for responding to environmental variation. However, until recently, suitable high-resolution data on the behaviour of seabirds and other CPFs at sea have not been available. Previous studies of breeding seabirds have investigated variation in foraging trip duration and colony attendance, but few studies have analyzed variation in time allocation within foraging trips. Here, we develop a conceptual energy-based model for analysing variation in the time allocation of CPFs during foraging trips, and apply it to the movement patterns of Peruvian boobies (Sula variegata). Foraging trips of Peruvian boobies, recorded using high-resolution global positioning systems (GPS), were first partitioned into movement modes consistent with travel and foraging behaviours using a hidden Markov model (HMM) adapted to account for gaps in the GPS tracks associated with diving behaviour. Analysis of the HMM results based on the conceptual model indicated that differences in foraging effort between two treatments were best explained by a combination of differences in travel time and in time spent searching for prey. The conceptual model provides the basis for an integrated approach to analysis of variation in foraging strategies in which identification of various behaviours is coupled with assessments of time and energy budgets. This integrated approach can contribute to greater understanding of the processes determining foraging strategies and the limits to these strategies in the context of competition for resources and global climate change.  
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  Éditeur de collection Titre de collection Titre de collection Abrégé  
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  ISSN 0304-3800 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 355  
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Auteur Lopez, N.; Navarro, J.; Barria, C.; Albo-Puigserver, M.; Coll, M.; Palomera, I. doi  openurl
  Titre Feeding ecology of two demersal opportunistic predators coexisting in the northwestern Mediterranean Sea Type Article scientifique
  Année 2016 Publication Revue Abrégée Estuar. Coast. Shelf Sci.  
  Volume 175 Numéro Pages (up) 15-23  
  Mots-Clés abundance; anglerfish lophius-budegassa; Black anglerfish; communities; diet; fish; habits; linnaeus; Lophius budegassa; Lophius piscatorius; osteichthyes; piscatorius; Spatial distributions; Stable isotopes; Stomach contents; Trophic ecology; White anglerfish  
  Résumé The study of the feeding ecology of marine organisms is crucial to understanding their ecological roles and advancing our knowledge of marine ecosystem functioning. The aim of this study was to analyse the trophic ecology of two demersal predator species, black anglerfish (Lophius budegassa) and white anglerfish (L. piscatorius), in the northwestern Mediterranean Sea. Both species are important in the study area due to their high abundance and economic value, but information about their feeding behaviour is scarce. Here, we described the diet composition and ecological role of these two species, investigating whether trophic segregation exists between them and amongst fish of different sizes. In addition, by using experimental survey data we described the spatial distribution of both species to help us interpret trophic behaviour patterns. We gathered samples of two different sizes (small individuals of a total length <30 cm and large individuals >= 30 cm) of both species and combined stomach content analyses (SCA) and stable isotope analyses (SIA) of nitrogen and carbon with isotopic mixing models. Our results revealed that both anglerfish species are opportunistic predators, showing a diet composed mainly of fishes and, to a lesser extent, of crustaceans, with a small proportion of cephalopods, gastropods, bivalves and echinoderms. We found trophic segregation between the two species and the two sizes, indicating that they feed on different prey, in line with differences in their spatial distribution within the study area. This partial partition of food resources could also be explained by the differences in rhythms of activity that were reported in previous studies. In addition, although both species occupied a high position within the food web, our results showed that white anglerfish individuals and the large-sized fish of both species held higher trophic positions. This study demonstrates the usefulness of complementary approaches for trophic studies and confirms that both anglerfish species play an important role as predators in the northwestern Mediterranean Sea food web. (C) 2016 Elsevier Ltd. All rights reserved.  
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  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0272-7714 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1647  
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Auteur Dupuy, C.; Pagano, M.; Got, P.; Domaizon, I.; Chappuis, A.; Marchessaux, G.; Bouvy, M. url  doi
openurl 
  Titre Trophic relationships between metazooplankton communities and their plankton food sources in the Iles Eparses (Western Indian Ocean) Type Article scientifique
  Année 2016 Publication Revue Abrégée Marine Environmental Research  
  Volume 116 Numéro Pages (up) 18-31  
  Mots-Clés feeding ecology; grazing effect; Iles Eparses; Mayotte; Metazooplankton; spatial distribution  
  Résumé Coral reef and atoll lagoons are among the most diversified marine ecosystems but also the most affected by the combined effects of climate change and human activities. The Iles Eparses (Scattered Islands) in the Western Indian Ocean have been little affected by human pressure and can be considered to be “pristine” ecosystems. Metazooplankton plays a major role in the functioning and productivity of aquatic ecosystems, and this study was undertaken: (i) to determine the spatial abundance, distribution and species composition of metazooplankton, (ii) to assess the effect of metazooplankton grazing on pico- and nanophytoplankton and (iii) to analyze the trophic positions of metazooplankton by using the stable isotope signatures of a wide variety of taxa and particulate organic matter from the Iles Eparses and Mayotte. Tromelin Island (which is not located in the Mozambique Channel) had the lowest metazooplankton abundance with no cyanobacteria Trichodesmium spp. or mollusks (pteropods) presence, and with δ15N signatures of organisms that were higher than for the islands in the Mozambique Channel. Trichodesmium spp. was found in the Mozambique Channel and the plankton food web was probably based preferentially on these cyanobacteria with lower δ15N signatures indicating direct or indirect trophic transfer of diazotrophic nitrogen to metazooplankton. Three of the islands were distinct: Europa had the highest proportion of copepods, with oithonids being dominant, which is typical of rich mangrove systems, while Juan de Nova and Mayotte seemed to be the sites most affected by human activity with a high abundance of appendicularians and distinct particulate organic matter ∂13C signatures. Grazing experiments showed that food could be a limiting factor for metazooplankton in the Iles Eparses. However, the effect of metazooplankton grazing on phytoplankton appeared to be very low (0.01–2.32% of the total phytoplankton per day).  
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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 0141-1136 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1496  
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Auteur Jeanmougin, M.; Leprieur, F.; Lois, G.; Clergeau, P. url  doi
openurl 
  Titre Fine-scale urbanization affects Odonata species diversity in ponds of a megacity (Paris, France) Type Article scientifique
  Année 2014 Publication Revue Abrégée Acta Oecologica-International Journal of Ecology  
  Volume 59 Numéro Pages (up) 26-34  
  Mots-Clés Evenness; Landscape composition; Model averaging; Ponds; Species diversity; Urban ecology; agricultural landscape; comparative biodiversity; conservation; dragonflies odonata; ecology; fresh-water habitat; patterns; richness; selection; urban  
  Résumé Current developments in urban ecology include very few studies focused on pond ecosystems, though ponds are recognized as biodiversity hotspots. Using Odonata as an indicator model, we explored changes in species composition in ponds localized along an urban gradient of a megacity (Paris, France). We then assessed the relative importance of local- and landscape-scale variables in shaping Odonata alpha-diversity patterns using a model-averaging approach. Analyses were performed for adult (A) and adult plus exuviae (AE) census data. At 26 ponds, we recorded 657 adults and 815 exuviae belonging to 17 Odonata species. The results showed that the Odonata species assemblage composition was not determined by pond localization along the urban gradient. Similarly, pond characteristics were found to be similar among urban, suburban and periurban ponds. The analyses of AE census data revealed that fine-scale urbanization (i.e., increased density of buildings surrounding ponds) negatively affects Odonata alpha-diversity. In contrast, pond localization along the urban gradient weakly explained the alpha-diversity patterns. Several local-scale variables, such as the coverage of submerged macrophytes, were found to be significant drivers of Odonata alpha-diversity. Together, these results show that the degree of urbanization around ponds must be considered instead of pond localization along the urban gradient when assessing the potential impacts of urbanization on Odonata species diversity This work also indicates the importance of exuviae sampling in understanding the response of Odonata to urbanization. (C) 2014 Elsevier Masson SAS. All rights reserved.  
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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 1146-609x ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 602  
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