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Author Rifflet, A.; Tene, N.; Orivel, J.; Treilhou, M.; Dejean, A.; Vetillard, A. pdf  url
openurl 
  Title Paralyzing Action from a Distance in an Arboreal African Ant Species Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS ONE  
  Volume 6 Issue 12 Pages (down) e28571  
  Keywords  
  Abstract Due to their prowess in interspecific competition and ability to catch a wide range of arthropod prey (mostly termites with which they are engaged in an evolutionary arms race), ants are recognized as a good model for studying the chemicals involved in defensive and predatory behaviors. Ants' wide diversity of nesting habits and relationships with plants and prey types implies that these chemicals are also very diverse. Using the African myrmicine ant Crematogaster striatula as our focal species, we adopted a three-pronged research approach. We studied the aggressive and predatory behaviors of the ant workers, conducted bioassays on the effect of their Dufour gland contents on termites, and analyzed these contents. (1) The workers defend themselves or eliminate termites by orienting their abdominal tip toward the opponent, stinger protruded. The chemicals emitted, apparently volatile, trigger the recruitment of nestmates situated in the vicinity and act without the stinger having to come into direct contact with the opponent. Whereas alien ants competing with C. striatula for sugary food sources are repelled by this behavior and retreat further and further away, termites defend their nest whatever the danger. They face down C. striatula workers and end up by rolling onto their backs, their legs batting the air. (2) The bioassays showed that the toxicity of the Dufour gland contents acts in a time-dependent manner, leading to the irreversible paralysis, and, ultimately, death of the termites. (3) Gas chromatography-mass spectrometry analyses showed that the Dufour gland contains a mixture of mono- or polyunsaturated long-chain derivatives, bearing functional groups like oxo-alcohols or oxo-acetates. Electrospray ionization-mass spectrometry showed the presence of a molecule of 1584 Da that might be a large, acetylated alkaloid capable of splitting into smaller molecules that could be responsible for the final degree of venom toxicity.  
  Address  
  Corporate Author Thesis  
  Publisher Public Library of Science Place of Publication Editor  
  Language Summary Language Original Title  
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  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 376  
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Author Dejean, A.; Cereghino, R.; Carpenter, J.M.; Corbara, B.; Herault, B.; Rossi, V.; Leponce, M.; Orivel, J.; Bonal, D. pdf  url
openurl 
  Title Climate change impact on neotropical social wasps Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS ONE  
  Volume 6 Issue 11 Pages (down) e27004  
  Keywords  
  Abstract Establishing a direct link between climate change and fluctuations in animal populations through long-term monitoring is difficult given the paucity of baseline data. We hypothesized that social wasps are sensitive to climatic variations, and thus studied the impact of ENSO events on social wasp populations in French Guiana. We noted that during the 2000 La Niña year there was a 77.1% decrease in their nest abundance along ca. 5 km of forest edges, and that 70.5% of the species were no longer present. Two simultaneous 13-year surveys (1997-2009) confirmed the decrease in social wasps during La Niña years (2000 and 2006), while an increase occurred during the 2009 El Niño year. A 30-year weather survey showed that these phenomena corresponded to particularly high levels of rainfall, and that temperature, humidity and global solar radiation were correlated with rainfall. Using the Self-Organizing Map algorithm, we show that heavy rainfall during an entire rainy season has a negative impact on social wasps. Strong contrasts in rainfall between the dry season and the short rainy season exacerbate this effect. Social wasp populations never recovered to their pre-2000 levels. This is probably because these conditions occurred over four years; heavy rainfall during the major rainy seasons during four other years also had a detrimental effect. On the contrary, low levels of rainfall during the major rainy season in 2009 spurred an increase in social wasp populations. We conclude that recent climatic changes have likely resulted in fewer social wasp colonies because they have lowered the wasps' resistance to parasitoids and pathogens. These results imply that Neotropical social wasps can be regarded as bio-indicators because they highlight the impact of climatic changes not yet perceptible in plants and other animals. © 2011 Dejean et al.  
  Address INRA – Nancy, UMR EEF, Champenou, Nancy, France  
  Corporate Author Thesis  
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  ISSN 19326203 (Issn) ISBN Medium  
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  Notes Export Date: 29 November 2011; Source: Scopus; Art. No.: e27004; doi: 10.1371/journal.pone.0027004; Language of Original Document: English; Correspondence Address: Dejean, A.; CNRS – UMR 8172, Écologie des Forêts de Guyane (Ecofog), Campus Agronomique, BP 709, Kourou, France; email: alain.dejean@wanadoo.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 372  
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Author Hibert, F.; Sabatier, D.; Andrivot, J.; Scotti-Saintagne, C.; Gonzalez, S.; Prévost, M.-F.; Grenand, P.; Chave, J.; Caron, H.; Richard-Hansen, C. pdf  url
openurl 
  Title Botany, genetics and ethnobotany: A crossed investigation on the elusive tapir's diet in French guiana Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS ONE  
  Volume 6 Issue 10 Pages (down) e25850  
  Keywords  
  Abstract While the populations of large herbivores are being depleted in many tropical rainforests, the importance of their trophic role in the ecological functioning and biodiversity of these ecosystems is still not well evaluated. This is due to the outstanding plant diversity that they feed upon and the inherent difficulties involved in observing their elusive behaviour. Classically, the diet of elusive tropical herbivores is studied through the observation of browsing signs and macroscopic analysis of faeces or stomach contents. In this study, we illustrate that the original coupling of classic methods with genetic and ethnobotanical approaches yields information both about the diet diversity, the foraging modalities and the potential impact on vegetation of the largest terrestrial mammal of Amazonia, the lowland tapir. The study was conducted in the Guianan shield, where the ecology of tapirs has been less investigated. We identified 92 new species, 51 new genera and 13 new families of plants eaten by tapirs. We discuss the relative contribution of our different approaches, notably the contribution of genetic barcoding, used for the first time to investigate the diet of a large tropical mammal, and how local traditional ecological knowledge is accredited and valuable for research on the ecology of elusive animals. © 2011 Hibert et al.  
  Address INRA, Université de Bordeaux, UMR1202 BIOGECO, Cestas, France  
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  ISSN 19326203 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 21 October 2011; Source: Scopus; Art. No.: e25850; doi: 10.1371/journal.pone.0025850; Language of Original Document: English; Correspondence Address: Hibert, F.; Direction Etudes et Recherches Guyane, Office National de la Chasse et de la Faune Sauvage, Kourou, French Guiana, France; email: fabricenz@gmail.com Approved no  
  Call Number EcoFoG @ webmaster @ Serial 343  
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Author Devault, D.A.; Beilvert, B.; Winterton, P. url  doi
openurl 
  Title Ship breaking or scuttling? A review of environmental, economic and forensic issues for decision support Type Journal Article
  Year 2017 Publication Environmental Science and Pollution Research Abbreviated Journal Environ. Sci. Pollut. Res.  
  Volume 24 Issue 33 Pages (down) 25741-25774  
  Keywords Artificial reef; Diving; Ship recycling; Ship Recycling Facilities; Shipbreaking; Tourism; Working conditions; Wrecks; artificial reef; coastal erosion; coastal zone management; cost-benefit analysis; decision support system; developing world; economic impact; environmental economics; environmental impact assessment; environmental issue; facility location; health and safety; invasive species; profitability; recycling; shipping; tourism; working conditions; wreck; analysis; decision support system; economics; international cooperation; pollution; prevention and control; procedures; recycling; ship; statistics and numerical data; Decision Support Techniques; Environmental Pollution; Internationality; Recycling; Ships  
  Abstract In a globalized world, the world trade fleet plays a pivotal role in limiting transport costs. But, the management of obsolete ships is an acute problem, with most Ship Recycling Facilities (SRF) situated in developing countries. They are renowned for their controversial work and safety conditions and their environmental impact. Paradoxically, dismantlement is paid for by the shipowners in accordance with international conventions therefore it is more profitable for them to sell off ships destined for scrapping. Scuttling, the alternative to scrapping, is assessed in the present review to compare the cost/benefit ratios of the two approaches. Although scrapping provides employment and raw materials – but with environmental, health and safety costs – scuttling provides fisheries and diving tourism opportunities but needs appropriate management to avoid organic and metal pollution, introduction of invasive species and exacerbation of coastal erosion. It is also limited by appropriate bottom depth, ship type and number. The present review inventories the environmental, health, safety, economic, and forensic aspects of each alternative. © 2016, Springer-Verlag Berlin Heidelberg.  
  Address Département Langues et Gestion, Université Toulouse III – Paul Sabatier, 118 route de Narbonne, Toulouse cedex 09, 31062, France  
  Corporate Author Thesis  
  Publisher Springer Verlag Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 09441344 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 869  
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Author Dejean, A.; Orivel, J.; Azémar, F.; Herault, B.; Corbara, B. pdf  url
doi  openurl
  Title A cuckoo-like parasitic moth leads African weaver ant colonies to their ruin Type Journal Article
  Year 2016 Publication Scientific Reports Abbreviated Journal Sci. Rep.  
  Volume 6 Issue Pages (down) 23778  
  Keywords  
  Abstract In myrmecophilous Lepidoptera, mostly lycaenids and riodinids, caterpillars trick ants into transporting them to the ant nest where they feed on the brood or, in the more derived 'cuckoo strategy', trigger regurgitations (trophallaxis) from the ants and obtain trophic eggs. We show for the first time that the caterpillars of a moth (Eublemma albifascia; Noctuidae; Acontiinae) also use this strategy to obtain regurgitations and trophic eggs from ants (Oecophylla longinoda). Females short-circuit the adoption process by laying eggs directly on the ant nests, and workers carry just-hatched caterpillars inside. Parasitized colonies sheltered 44 to 359 caterpillars, each receiving more trophallaxis and trophic eggs than control queens. The thus-starved queens lose weight, stop laying eggs (which transport the pheromones that induce infertility in the workers) and die. Consequently, the workers lay male-destined eggs before and after the queen's death, allowing the colony to invest its remaining resources in male production before it vanishes.  
  Address Université Clermont Auvergne, Université Blaise Pascal (LMGE), Clermont-Ferrand, France  
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  Notes Export Date: 22 April 2016 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 674  
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Author Piponiot, C.; Sist, P.; Mazzei, L.; Peña-Claros, M.; Putz, F.E.; Rutishauser, E.; Shenkin, A.; Ascarrunz, N.; de Azevedo, C.P.; Baraloto, C.; França, M.; Guedes, M.; Honorio Coronado, E.N.; d'Oliveira, M.V.N.; Ruschel, A.R.; da Silva, K.E.; Doff Sotta, E.; de Souza, C.R.; Vidal, E.; West, T.A.P.; Herault, B. pdf  url
doi  openurl
  Title Carbon recovery dynamics following disturbance by selective logging in Amazonian forests Type Journal Article
  Year 2016 Publication eLife Abbreviated Journal  
  Volume 5 Issue Pages (down) e21394  
  Keywords  
  Abstract When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach, calibrated on a network of 133 permanent forest plots (175 ha total) across Amazonia, we link regional differences in climate, soil and initial biomass with survivors' and recruits' C fluxes to provide Amazon-wide predictions of post-logging C recovery. We show that net aboveground C recovery over 10 years is higher in the Guiana Shield and in the west (21{plus minus}3 MgC ha-1) than in the south (12{plus minus}3 MgC ha-1) where environmental stress is high (low rainfall, high seasonality). We highlight the key role of survivors in the forest regrowth and elaborate a comprehensive map of post-disturbance C recovery potential in Amazonia.  
  Address  
  Corporate Author Thesis  
  Publisher eLife Sciences Publications, Ltd Place of Publication Editor Trumbore, S.  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-084x ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 702  
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Author Roux, O.; Cereghino, R.; Solano, P.J.; Dejean, A. pdf  openurl
  Title Caterpillars and Fungal Pathogens: Two Co-Occurring Parasites of an Ant-Plant Mutualism Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 6 Issue 5 Pages (down) e20538  
  Keywords  
  Abstract In mutualisms, each interacting species obtains resources from its partner that it would obtain less efficiently if alone, and so derives a net fitness benefit. In exchange for shelter (domatia) and food, mutualistic plant-ants protect their host myrmecophytes from herbivores, encroaching vines and fungal pathogens. Although selective filters enable myrmecophytes to host those ant species most favorable to their fitness, some insects can by-pass these filters, exploiting the rewards supplied whilst providing nothing in return. This is the case in French Guiana for Cecropia obtusa (Cecropiaceae) as Pseudocabima guianalis caterpillars (Lepidoptera, Pyralidae) can colonize saplings before the installation of their mutualistic Azteca ants. The caterpillars shelter in the domatia and feed on food bodies (FBs) whose production increases as a result. They delay colonization by ants by weaving a silk shield above the youngest trichilium, where the FBs are produced, blocking access to them. This probable temporal priority effect also allows female moths to lay new eggs on trees that already shelter caterpillars, and so to occupy the niche longer and exploit Cecropia resources before colonization by ants. However, once incipient ant colonies are able to develop, they prevent further colonization by the caterpillars. Although no higher herbivory rates were noted, these caterpillars are ineffective in protecting their host trees from a pathogenic fungus, Fusarium moniliforme (Deuteromycetes), that develops on the trichilium in the absence of mutualistic ants. Therefore, the Cecropia treelets can be parasitized by two often overlooked species: the caterpillars that shelter in the domatia and feed on FBs, delaying colonization by mutualistic ants, and the fungal pathogen that develops on old trichilia. The cost of greater FB production plus the presence of the pathogenic fungus likely affect tree growth.  
  Address [Roux, Olivier; Dejean, Alain] CNRS, Ecol Forets Guyane UMR 8172, Kourou, France, Email: olivier.roux@ird.fr  
  Corporate Author Thesis  
  Publisher Public Library Science Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000291097600091 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 322  
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Author Brouard, O.; Le Jeune, A.H.; Leroy, C.; Cereghino, R.; Roux, O.; Pelozuelo, L.; Dejean, A.; Corbara, B.; Carrias, J.F. pdf  openurl
  Title Are Algae Relevant to the Detritus-Based Food Web in Tank-Bromeliads? Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 6 Issue 5 Pages (down) e20129  
  Keywords  
  Abstract We assessed the occurrence of algae in five species of tank-bromeliads found in contrasting environmental sites in a Neotropical, primary rainforest around the Nouragues Research Station, French Guiana. The distributions of both algal abundance and biomass were examined based on physical parameters, the morphological characteristics of bromeliad species and with regard to the structure of other aquatic microbial communities held in the tanks. Algae were retrieved in all of the bromeliad species with mean densities ranging from similar to 10(2) to 10(4) cells/mL. Their biomass was positively correlated to light exposure and bacterial biomass. Algae represented a tiny component of the detrital food web in shaded bromeliads but accounted for up to 30 percent of the living microbial carbon in the tanks of Catopsis berteroniana, located in a highly exposed area. Thus, while nutrient supplies are believed to originate from wind-borne particles and trapped insects (i.e., allochtonous organic matter), our results indicate that primary producers (i.e., autochtonous organic matter) are present in this insectivorous bromeliad. Using a 24-h incubation of size-fractionated and manipulated samples from this plant, we evaluated the impact of mosquito foraging on algae, other microorganisms and rotifers. The prey assemblages were greatly altered by the predation of mosquito larvae. Grazing losses indicated that the dominant algal taxon, Bumilleriopsis sp., like protozoa and rotifers, is a significant part of the diet of mosquito larvae. We conclude that algae are a relevant functional community of the aquatic food web in C. berteroniana and might form the basis of a complementary non-detrital food web.  
  Address [Brouard, Olivier; Le Jeune, Anne-Helene; Corbara, Bruno; Carrias, Jean-Francois] Univ Clermont Ferrand, CNRS, Lab Microorganismes Genome & Environm, LMGE,UMR 6023, Aubiere, France, Email: j-francois.carrias@univ-bpclermont.fr  
  Corporate Author Thesis  
  Publisher Public Library Science Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000290720200066 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 319  
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Author Dejean, A. pdf  openurl
  Title Prey Capture Behavior in an Arboreal African Ponerine Ant Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 6 Issue 5 Pages (down) e19837  
  Keywords  
  Abstract I studied the predatory behavior of Platythyrea conradti, an arboreal ponerine ant, whereas most species in this subfamily are ground-dwelling. The workers, which hunt solitarily only around dusk, are able to capture a wide range of prey, including termites and agile, nocturnal insects as well as diurnal insects that are inactive at that moment of the Nyctemeron, resting on tree branches or under leaves. Prey are captured very rapidly, and the antennal palpation used by ground-dwelling ponerine species is reduced to a simple contact; stinging occurs immediately thereafter. The venom has an instant, violent effect as even large prey (up to 30 times the weight of a worker) never struggled after being stung. Only small prey are not stung. Workers retrieve their prey, even large items, singly. To capture termite workers and soldiers defending their nest entrances, ant workers crouch and fold their antennae backward. In their role as guards, the termites face the crouching ants and end up by rolling onto their backs, their legs batting the air. This is likely due to volatile secretions produced by the ants' mandibular gland. The same behavior is used against competing ants, including territorially-dominant arboreal species that retreat further and further away, so that the P. conradti finally drive them from large, sugary food sources.  
  Address [Dejean, Alain] CNRS, Ecol Forets Guyane UMR 8172, Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher Public Library Science Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000290483600033 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 316  
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Author Dejean, A.; Corbara, B.; Leroy, C.; Delabie, J.H.C.; Rossi, V.; Cereghino, R. pdf  openurl
  Title Inherited Biotic Protection in a Neotropical Pioneer Plant Type Journal Article
  Year 2011 Publication PLoS One Abbreviated Journal PLoS One  
  Volume 6 Issue 3 Pages (down) e18071  
  Keywords  
  Abstract Chelonanthus alatus is a bat-pollinated, pioneer Gentianaceae that clusters in patches where still-standing, dried-out stems are interspersed among live individuals. Flowers bear circum-floral nectaries (CFNs) that are attractive to ants, and seed dispersal is both barochorous and anemochorous. Although, in this study, live individuals never sheltered ant colonies, dried-out hollow stems – that can remain standing for 2 years – did. Workers from species nesting in dried-out stems as well as from ground-nesting species exploited the CFNs of live C. alatus individuals in the same patches during the daytime, but were absent at night (when bat pollination occurs) on 60.5% of the plants. By visiting the CFNs, the ants indirectly protect the flowers – but not the plant foliage – from herbivorous insects. We show that this protection is provided mostly by species nesting in dried-out stems, predominantly Pseudomyrmex gracilis. That dried-out stems remain standing for years and are regularly replaced results in an opportunistic, but stable association where colonies are sheltered by one generation of dead C. alatus while the live individuals nearby, belonging to the next generation, provide them with nectar; in turn, the ants protect their flowers from herbivores. We suggest that the investment in wood by C. alatus individuals permitting still-standing, dried-out stems to shelter ant colonies constitutes an extended phenotype because foraging workers protect the flowers of live individuals in the same patch. Also, through this process these dried-out stems indirectly favor the reproduction (and so the fitness) of the next generation including both their own offspring and that of their siblings, all adding up to a potential case of inclusive fitness in plants.  
  Address [Dejean, Alain; Leroy, Celine] CNRS, Ecol Forets Guyane UMR CNRS 8172, Kourou, France, Email: alain.dejean@wanadoo.fr  
  Corporate Author Thesis  
  Publisher Public Library Science Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000289057200023 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 306  
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