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Auteur Colin, N.; Villeger, S.; Wilkes, M.; de Sostoa, A.; Maceda-Veiga, A. doi  openurl
  Titre (up) Functional diversity measures revealed impacts of non-native species and habitat degradation on species-poor freshwater fish assemblages Type Article scientifique
  Année 2018 Publication Revue Abrégée Sci. Total Environ.  
  Volume 625 Numéro Pages 861-871  
  Mots-Clés biodiversity; ecosystems; community; life-history traits; Non-native species; 4th-corner problem; Functional diversity; Fish assemblages; Biomonitoring; ecological quality; flow regime; Human disturbance; mediterranean rivers; Mediterranean rivers; stream; traits-environment relationships  
  Résumé Trail-based ecology has been developed for decades lo infer ecosystem responses to stressors based on the functional structure of communities, yet its value in species-poor systems is largely unknown. Here, we used an extensive clataset in a Spanish region highly prone to non-native fish invasions (15 catchments, N 389 sites) to assess for the first time how species-poor communities respond to large-scale environmental gradients using a taxonomic and functional trait-based approach in riverine fish. We examined total species richness and three functional trait-based indices available when many sites have <= 3 species (specialization, FSpe; onginaliy, FOri and entropy, FEnt). We assessed the responses of these taxonomic and functional indices along gradients of altitude, water pollution, physical habitat degradation and non-native fish biomass. Whilst species richness was relatively sensitive to spatial effects, functional diversity indices were responsive across natural and anthropogenic gradients. All four diversity measures declined with altitude but this decline was modulated by physical habitat degradation (richness, FSpe and FEnt) and the non-native total fish biomass ratio (FSpe and FOri) in ways that varied between indices. Furthermore, FSpe and FOri were significantly correlated with Total Nitrogen. Non-native fish were a major component of the taxonomic and functional structure of fish communities, raising concerns about potential misdiagnosis between invaded and environmentally-degraded river reaches. Such misdiagnosis was evident in a regional fish index widely used in official monitoring programs. We recommend the application of FSpe and FOri to extensive clatasets from monitoring programs in order to generate valuable cross-system information about the impacts of non-native species and habitat degradation, even in species-poor systems. Scoring non-native species apart from habitat degradation in the indices used to determine ecosystem health is essential to develop better management strategies. (C) 2013 Elsevier B.V. All rights reserved.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0048-9697 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2309  
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Auteur Villeger, S.; Grenouillet, G.; Brosse, S. url  doi
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  Titre (up) Functional homogenization exceeds taxonomic homogenization among European fish assemblages Type Article scientifique
  Année 2014 Publication Revue Abrégée Global Ecology and Biogeography  
  Volume 23 Numéro 12 Pages 1450-1460  
  Mots-Clés beta-diversity; exotic species; functional diversity; Non-native species; taxonomic dissimilarity; translocation  
  Résumé Aim Human activities and the consequent extirpations of native species and introductions of non-native species have been modifying the composition of species assemblages throughout the world. These anthropogenic impacts have modified the richness of assemblages as well as the biological dissimilarity among them. However, while changes in taxonomic dissimilarity (i.e. accounting for species composition) have been assessed intensively during the last decade there are still few assessments of changes in functional dissimilarity (i.e. accounting for the diversity of biological traits). Here, we assess the temporal changes in both taxonomic and functional dissimilarities for freshwater fish assemblages across Europe. Location Western Palaearctic, 137 river basins. Methods The Jaccard index was used to quantify the changes in both taxonomic and functional dissimilarity. We then partitioned dissimilarity to extract its turnover component and measured the changes in the contribution of turnover to dissimilarity. Results Functional homogenization exceeded taxonomic homogenization six-fold. More importantly, we found only a moderate positive correlation between these changes. For instance, 40% of assemblages that experienced taxonomic differentiation were actually functionally homogenized. Taxonomic and functional homogenizations were stronger when the historical level of taxonomic dissimilarity among assemblages was high and when a high number of non-native species were introduced in the assemblages. Moreover, translocated species (i.e. non-native species originating from Europe) played a stronger role than exotic species (i.e. those coming from outside Europe) in this homogenization process, while extirpation did not play a significant role. Main conclusions Change in taxonomic diversity cannot be used to predict changes in functional diversity. In addition, as functional diversity has been proven to be a better indicator of ecosystem functioning and stability than taxonomic diversity, further studies are required to test the potential effects of functional homogenization at the local scale.  
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  Volume de collection Numéro de collection Edition  
  ISSN 1466-8238 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1178  
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Auteur Mouillot, D.; Parravicini, V.; Bellwood, D.R.; Leprieur, F.; Huang, D.; Cowman, P.F.; Albouy, C.; Hughes, T.P.; Thuiller, W.; Guilhaumon, F. doi  openurl
  Titre (up) Global marine protected areas do not secure the evolutionary history of tropical corals and fishes Type Article scientifique
  Année 2016 Publication Revue Abrégée Nat. Commun.  
  Volume 7 Numéro Pages 10359  
  Mots-Clés Biodiversity; conservation; extinction risk; functional diversity; management; patterns; phylogenetic diversity; reef fisheries; species richness; vulnerability  
  Résumé Although coral reefs support the largest concentrations of marine biodiversity worldwide, the extent to which the global system of marine-protected areas (MPAs) represents individual species and the breadth of evolutionary history across the Tree of Life has never been quantified. Here we show that only 5.7% of scleractinian coral species and 21.7% of labrid fish species reach the minimum protection target of 10% of their geographic ranges within MPAs. We also estimate that the current global MPA system secures only 1.7% of the Tree of Life for corals, and 17.6% for fishes. Regionally, the Atlantic and Eastern Pacific show the greatest deficit of protection for corals while for fishes this deficit is located primarily in the Western Indian Ocean and in the Central Pacific. Our results call for a global coordinated expansion of current conservation efforts to fully secure the Tree of Life on coral reefs.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 2041-1723 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1506  
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Auteur Parravicini, V.; Villeger, S.; McClanahan, T.R.; Arias-Gonzalez, J.E.; Bellwood, D.R.; Belmaker, J.; Chabanet, P.; Floeter, S.R.; Friedlander, A.M.; Guilhaumon, F.; Vigliola, L.; Kulbicki, M.; Mouillot, D. url  doi
openurl 
  Titre (up) Global mismatch between species richness and vulnerability of reef fish assemblages Type Article scientifique
  Année 2014 Publication Revue Abrégée Ecology Letters  
  Volume 17 Numéro 9 Pages 1101-1110  
  Mots-Clés Vulnerability; biodiversity; biodiversity loss; conservation; coral-reefs; extinction; fisheries; functional diversity; hotspots; macroecology; marine; patterns; protected areas; risk assessment; sensitivity  
  Résumé The impact of anthropogenic activity on ecosystems has highlighted the need to move beyond the biogeographical delineation of species richness patterns to understanding the vulnerability of species assemblages, including the functional components that are linked to the processes they support. We developed a decision theory framework to quantitatively assess the global taxonomic and functional vulnerability of fish assemblages on tropical reefs using a combination of sensitivity to species loss, exposure to threats and extent of protection. Fish assemblages with high taxonomic and functional sensitivity are often exposed to threats but are largely missed by the global network of marine protected areas. We found that areas of high species richness spatially mismatch areas of high taxonomic and functional vulnerability. Nevertheless, there is strong spatial match between taxonomic and functional vulnerabilities suggesting a potential win-win conservation-ecosystem service strategy if more protection is set in these locations.  
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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 1461-023x ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 630  
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Auteur Manna, L.R.; Villeger, S.; Rezende, C.F.; Mazzoni, R. doi  openurl
  Titre (up) High intraspecific variability in morphology and diet in tropical stream fish communities Type Article scientifique
  Année 2019 Publication Revue Abrégée Ecol. Freshw. Fish  
  Volume 28 Numéro 1 Pages 41-52  
  Mots-Clés approach reveals; assemblages; body-size; community ecology; competition; ecology; functional diversity; functional traits; habitat use; originality; plasticity; rainforest stream; savannah stream; specialisation; specialization; traits  
  Résumé Functional diversity of fish communities has been measured according to (a) interspecific variability, assuming that intraspecific variability is negligible, or (b) morphological differences, as good descriptors of complex functions, such as diet. These two assumptions have been scarcely tested on the individual level, especially in species-rich tropical ecosystems. Here, we adapted intraspecific specialisation (ISpe) and intraspecific originality indices (IOri) to assess complementary components of intraspecific variability. Next, we applied these indices to evaluate the intra- and interspecific variability of morphological and diet traits in two contrasting Brazilian stream-dwelling fish assemblages (rainforest and savannah). We also compared correlations between morphology and diet at the individual and species level to test whether accounting for intraspecific variability increases the predictability of diet due to morphological differences. Significant contributions of intraspecific variability to differences between fish were revealed for morphology and diet. Intraspecific variability in the diet was higher than that in morphology in both assemblages. The ISpe was positively correlated to IOri in the diet of both ecosystems. The morphological-dietary relationships were significant but weak at both individual and species levels. Our findings highlight the importance of measuring individual variability and accounting for complementary components of the intraspecific variability (ISpe and IOri). Importantly, we showed that the variability in morphology does not predict diet variability at both intra- and interspecific levels. Thus, high intraspecific variability in morphology and diet challenges the use of functional traits measured at the species level to describe the functional diversity of different fish assemblages.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
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  ISSN 0906-6691 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2472  
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