Methylmercury effects on migratory behaviour in glass eels (Anguilla anguilla) : an experimental study using isotopic tracers

• Published in: Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology
• Main Authors: Claveau, Julie, Monperrus, Mathilde, Jarry, Marc, Baudrimont, Magalie, Gonzalez, Patrice, Cavalheiro, Joana, Mesmer-Dudons, Nathalie, Bolliet, Valérie
• Other Authors: Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP), Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), The project was partly supported by funding from the European Union within the framework of the ORQUE SUDOE project (SOE3/P2/F591), the Conseil Général des Pyrénées Atlantiques within the framework of the EXPLOR project and by the University of Pau (BQR MIRA)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2015
• Subjects: isotopic tracer; antioxidative defence; migratory behaviour; glass eel; anguillidae; methylmercury; traceur isotopique; pollution; déméthylation; comportement migratoire; anguilla anguilla; méthyle mercure; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Anguilla anguilla
• Online Access: https://hal.archives-ouvertes.fr/hal-01901354; https://doi.org/10.1016/j.cbpc.2015.03.003

International audience The effect of methylmercury (MeHg) on glass eels' propensity to migrate, mitochondrial activity and antioxidative defence systems was investigated. Marine glass eels were first sorted in an experimental flume according to their response to dusk. Fish responding to the decrease in light intensity by ascending in the water column and moving with or against the flow were considered as having a high propensity to migrate (migrant). Glass eels still sheltering at the end of the 24 h catching period were considered as having a low propensity to migrate and were called non-migrant. Migrant and non-migrant glass eels were then individually tagged and exposed to isotopically enriched 201MeHg (50 ng L− 1) for 11 days. The effect of contamination was studied on muscle fibre structure, and the expression level of genes involved in mitochondrial activity and antioxidative defence systems. To investigate the effect of MeHg on glass eel behaviour, migrant and non-migrant glass eels were sorted again and the bioaccumulation of 201MeHg and its demethylation product (201Hg(II)) were determined for each individual. MeHg exposure increased activity in non-migrant glass eels but not migratory behaviour. Contamination affected mitochondrial structure and metabolism and suggests a higher oxidative stress and activation of antioxidative defence systems in non-migrant glass eels. Overall, our results suggest that exposure to MeHg might induce an increase in energy expenditure and a higher vulnerability to predation in non-migrant glass eels in the wild