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Auteur Ottimofiore, E.; Albouy, C.; Leprieur, F.; Descombes, P.; Kulbicki, M.; Mouillot, D.; Parravicini, V.; Pellissier, L. doi  openurl
  Titre Responses of coral reef fishes to past climate changes are related to life-history traits Type Article scientifique
  Année 2017 Publication Revue Abrégée Ecol. Evol.  
  Volume 7 Numéro 6 Pages (down) 1996-2005  
  Mots-Clés climate change; dispersal; diversity; environmental-change; future; global patterns; Indo-Pacific Ocean; range shifts; refugia; richness; sea-level; species distribution; species distribution models; temperature  
  Résumé Coral reefs and their associated fauna are largely impacted by ongoing climate change. Unravelling species responses to past climatic variations might provide clues on the consequence of ongoing changes. Here, we tested the relationship between changes in sea surface temperature and sea levels during the Quaternary and present-day distributions of coral reef fish species. We investigated whether species-specific responses are associated with life-history traits. We collected a database of coral reef fish distribution together with life-history traits for the Indo-Pacific Ocean. We ran species distribution models (SDMs) on 3,725 tropical reef fish species using contemporary environmental factors together with a variable describing isolation from stable coral reef areas during the Quaternary. We quantified the variance explained independently by isolation from stable areas in the SDMs and related it to a set of species traits including body size and mobility. The variance purely explained by isolation from stable coral reef areas on the distribution of extant coral reef fish species largely varied across species. We observed a triangular relationship between the contribution of isolation from stable areas in the SDMs and body size. Species, whose distribution is more associated with historical changes, occurred predominantly in the Indo-Australian archipelago, where the mean size of fish assemblages is the lowest. Our results suggest that the legacy of habitat changes of the Quaternary is still detectable in the extant distribution of many fish species, especially those with small body size and the most sedentary. Because they were the least able to colonize distant habitats in the past, fish species with smaller body size might have the most pronounced lags in tracking ongoing climate change.  
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  Langue English Langue du Résumé Titre Original  
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  ISSN 2045-7758 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2108  
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Auteur Auguet, J.C.; Nomokonova, N.; Camarero, L.; Casamayor, E.O. doi  openurl
  Titre Seasonal changes of freshwater ammonia-oxidizing archaeal assemblages and nitrogen species in oligotrophic alpine lakes Type Article scientifique
  Année 2011 Publication Revue Abrégée Appl Environ Microbiol  
  Volume 77 Numéro 6 Pages (down) 1937-1945  
  Mots-Clés 16S/genetics Seasons Spain; Ammonia/*metabolism Archaea/classification/genetics/*metabolism Biodiversity Fresh Water Molecular Sequence Data Nitrogen/*metabolism Oxidoreductases/genetics Phylogeny Polymerase Chain Reaction RNA; Ribosomal  
  Résumé The annual changes in the composition and abundance of ammonia-oxidizing archaea (AOA) were analyzed monthly in surface waters of three high mountain lakes within the Limnological Observatory of the Pyrenees (LOOP; northeast Spain) using both 16S rRNA and functional (ammonia monooxygenase gene, amoA) gene sequencing as well as quantitative PCR amplification. The set of biological data was related to changes in nitrogen species and to other relevant environmental variables. The whole archaeal assemblage was dominated by phylotypes closely related to the crenarchaeal 1.1a group (58% +/- 18% of total 16S rRNA gene sequences), and consistent structural changes were detected during the study. Water temperature was the environmental variable that better explained spring, summer, and winter (ice-covered lakes) archaeal assemblage structure. The amoA gene was detected year round, and seasonal changes in amoA gene composition were well correlated with changes in the archaeal 16S rRNA gene pool. In addition, copy numbers of both the specific 1.1a group 16 rRNA and archaeal amoA genes were well correlated, suggesting that most freshwater 1.1a Crenarchaeota had the potential to carry out ammonia oxidation. Seasonal changes in the diversity and abundance of AOA (i.e., amoA) were better explained by temporal changes in ammonium, the substrate for nitrification, and mostly nitrite, the product of ammonia oxidation. Lacustrine amoA gene sequences grouped in coherent freshwater phylogenetic clusters, suggesting that freshwater habitats harbor typical amoA-containing ecotypes, which is different from soils and seas. We observed within the freshwater amoA gene sequence pool a high genetic divergence (translating to up to 32% amino acid divergence) between the spring and the remaining AOA assemblages. This suggests that different AOA ecotypes are adapted to different temporal ecological niches in these lakes.  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1304  
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Auteur Putman, N.F.; Verley, P.; Shay, T.J.; Lohmann, K.J. url  doi
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  Titre Simulating transoceanic migrations of young loggerhead sea turtles : merging magnetic navigation behavior with an ocean circulation model Type Article scientifique
  Année 2012 Publication Revue Abrégée Journal of Experimental Biology  
  Volume 215 Numéro 11 Pages (down) 1863-1870  
  Mots-Clés dispersal; Distribution; loggerhead sea turtle; magnetic map; magnetorecpetion; ocean circulation model  
  Résumé Young loggerhead sea turtles (Caretta caretta) from eastern Florida, USA, undertake a transoceanic migration in which they gradually circle the Sargasso Sea before returning to the North American coast. Loggerheads possess a. magnetic map' in which regional magnetic fields elicit changes in swimming direction along the migratory pathway. In some geographic areas, however, ocean currents move more rapidly than young turtles can swim. Thus, the degree to which turtles can control their migratory movements has remained unclear. In this study, the movements of young turtles were simulated within a high-resolution ocean circulation model using several different behavioral scenarios, including one in which turtles drifted passively and others in which turtles swam briefly in accordance with experimentally derived data on magnetic navigation. Results revealed that small amounts of oriented swimming in response to regional magnetic fields profoundly affected migratory routes and endpoints. Turtles that engaged in directed swimming for as little as 1-3 h per day were 43-187% more likely than passive drifters to reach the Azores, a productive foraging area frequented by Florida loggerheads. They were also more likely to remain within warm-water currents favorable for growth and survival, avoid areas on the perimeter of the migratory route where predation risk and thermal conditions pose threats, and successfully return to the open-sea migratory route if carried into coastal areas. These findings imply that even weakly swimming marine animals may be able to exert strong effects on their migratory trajectories and open-sea distributions through simple navigation responses and minimal swimming.  
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  ISSN 0022-0949 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 215  
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Auteur Duponchelle, F.; Pouilly, M.; Pecheyran, C.; Hauser, M.; Renno, J.-F.; Panfili, J.; Darnaude, A.M.; Garcia-Vasquez, A.; Carvajal-Vallejos, F.; Garcia-Davila, C.; Doria, C.; Berail, S.; Donard, A.; Sondag, F.; Santos, R.V.; Nunez, J.; Point, D.; Labonne, M.; Baras, E. doi  openurl
  Titre Trans-Amazonian natal homing in giant catfish Type Article scientifique
  Année 2016 Publication Revue Abrégée J. Appl. Ecol.  
  Volume 53 Numéro 5 Pages (down) 1511-1520  
  Mots-Clés Amazon; anthropogenic activities; brachyplatystoma-rousseauxii; Brachyplatystoma spp.; fisheries; fish otoliths; freshwater fish; giant catfish; hydroelectric dams; hydropower; isotopic signatures; markers; mass spectrometry; migration; migratory catfish; otoliths; pimelodidae; river; Sr-87/Sr-86 ratios  
  Résumé 1. Knowledge of fish migration is a prerequisite to sustainable fisheries management and preservation, especially in large international river basins. In particular, understanding whether a migratory lifestyle is compulsory or facultative, and whether adults home to their natal geographic area is paramount to fully appraise disruptions of longitudinal connectivity resulting from damming. 2. In the Amazon, the large migratory catfishes of the Brachyplatystoma genus are apex predators of considerable interest for fisheries. They are believed to use the entire length of the basin to perform their life cycle, with hypothesized homing behaviours. Here, we tested these hypotheses, using the emblematic B. rousseauxii as a model species. 3. We sampled adults close to major breeding areas in the Amazon basin (upper Madeira and upper Amazonas) and assessed their lifetime movements by measuring variations in Sr-87/Sr-86 along transverse sections of their otoliths (ear stones) using laser ablation multicollector mass spectrometry (LA-MC-ICPMS). 4. We demonstrate that larvae migrate downstream from the Andean piedmont to the lower Amazon, where they grow over a protracted period before migrating upstream as adults. Contrary to prevailing inferences, not all fish spend their nursery stages in the Amazon estuary,. By contrast, the passage in the lower or central Amazon seems an obligate part of the life cycle. We further evidence that most adults home to their natal geographic area within the Madeira sub-basin. Such long-distance natal homing is exceptional in purely freshwater fishes. 5. Synthesis and applications. By using otolith microchemistry, we were able to demonstrate a seemingly compulsory basin-wide migratory life cycle of large Amazonian catfishes. This makes them the organisms performing the longest migrations ( >8000 km) in fresh waters. This exceptional life history is already jeopardized by two dams recently built in the Madeira River, which block a major migration route and access to a substantial part of their spawning grounds. Major impacts can be anticipated from the current and forthcoming hydroelectric development in the Amazon basin, not only on the populations and fisheries of this apex predator, but also on Amazonian food webs through trophic cascades.  
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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 0021-8901 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1693  
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Auteur Dalongeville, A.; Andrello, M.; Mouillot, D.; Lobreaux, S.; Fortin, M.-J.; Lasram, F.; Belmaker, J.; Rocklin, D.; Manel, S. doi  openurl
  Titre Geographic isolation and larval dispersal shape seascape genetic patterns differently according to spatial scale Type Article scientifique
  Année 2018 Publication Revue Abrégée Evol. Appl.  
  Volume 11 Numéro 8 Pages (down) 1437-1447  
  Mots-Clés caribbean reef fish; connectivity; divergent selection; ecological data; ecological genetics; landscape genetics; marine connectivity; marine fish; Mediterranean Sea; Mullus surmuletus; neighbor matrices; oceanography; population-structure; sea; seascape genetics; single nucleotide polymorphism; surmuletus  
  Résumé Genetic variation, as a basis of evolutionary change, allows species to adapt and persist in different climates and environments. Yet, a comprehensive assessment of the drivers of genetic variation at different spatial scales is still missing in marine ecosystems. Here, we investigated the influence of environment, geographic isolation, and larval dispersal on the variation in allele frequencies, using an extensive spatial sampling (47 locations) of the striped red mullet (Mullus surmuletus) in the Mediterranean Sea. Univariate multiple regressions were used to test the influence of environment (salinity and temperature), geographic isolation, and larval dispersal on single nucleotide polymorphism (SNP) allele frequencies. We used Moran's eigenvector maps (db-MEMs) and asymmetric eigenvector maps (AEMs) to decompose geographic and dispersal distances in predictors representing different spatial scales. We found that salinity and temperature had only a weak effect on the variation in allele frequencies. Our results revealed the predominance of geographic isolation to explain variation in allele frequencies at large spatial scale (>1,000km), while larval dispersal was the major predictor at smaller spatial scale (<1,000km). Our findings stress the importance of including spatial scales to understand the drivers of spatial genetic variation. We suggest that larval dispersal allows to maintain gene flows at small to intermediate scale, while at broad scale, genetic variation may be mostly shaped by adult mobility, demographic history, or multigenerational stepping-stone dispersal. These findings bring out important spatial scale considerations to account for in the design of a protected area network that would efficiently enhance protection and persistence capacity of marine species.  
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  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1752-4571 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2422  
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