Factors determining survival of European eels in two unexploited sub-populations

• Published in: Freshwater Biology
• Main Authors: Boulenger, Clarisse, Acou, Anthony, Gimenez, Olivier, Charrier, Fabien, Tremblay, Julien, Feunteun, Eric
• Other Authors: Écologie et santé des écosystèmes (ESE), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Fish Pass, Unité d'Ecologie et Ecotoxicologie Aquatiques (UEEA), Institut National de la Recherche Agronomique (INRA), Pôle Gest'Aqua, Institut National de la Recherche Agronomique (INRA)-Office national de l'eau et des milieux aquatiques (ONEMA), Ministère de l'écologie, du développement durable et de l'énergie-Ministère de l'écologie, du développement durable et de l'énergie, MAVA Foundation
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: European eel; Life-history characteristics; sex ratio; survival; anguilla-anguilla l; [SDV]Life Sciences [q-bio]; Anguilla anguilla
• Online Access: https://hal.science/hal-01602451; https://doi.org/10.1111/fwb.12759

Boulenger, Clarisse Acou, Anthony Gimenez, Olivier Charrier, Fabien Tremblay, Julien Feunteun, EricRegion Bretagne; MAVA Foundation; Bretagne Grands MigrateursThis study was funded by the 'Region Bretagne', the MAVA Foundation, and 'Bretagne Grands Migrateurs'. The surveys and sampling were organised and operated by the company FISH PASS and the association 'Coeur Emeraude' in the Fremur River, and the INRA-Rennes and ONEMA in the Oir River. We are especially grateful to Frederic Marchand (INRA), Julien Tremblay (INRA), Richard Delanoe (ONEMA), Virgile Mazel (FISH PASS), Sebastien Quinot (FISH PASS) and all the people that helped with sampling and data gathering. We are also grateful to ORE PFC for the salmonid data.Wiley-blackwellHoboken Estimating accurate age-specific survival probabilities and understanding the processes (density dependent or independent) that regulate this demographic parameter are fundamental to propose sustainable management options for the endangered European eel (Anguilla anguilla). In the present study, we used extensive mark-recapture data sets (13 and 17years) on eel >150mm to estimate accurate natural survival probabilities of two eel sub-populations, from the Oir and Fremur rivers, western France, and then we analysed survival probabilities in relation to density-independent (temperature) and density-dependent factors to identify those causing survival variability. The Fremur and Oir rivers are two small (<100km(2)) river systems in close proximity (65km apart). The Fremur River is a small river obstructed by dams with medium water quality, high eel recruitment and density (0.37eelm(-2)), and a male dominant population; whereas, in the Oir River, low densities of eels were observed (0.04eelm(-2)) and the sex ratio was skewed towards females. Furthermore, previous research suggested that the lotic habitats of the Fremur River have reached carrying capacity, whereas habitats in the Oir River are below habitat saturation. In the Fremur River, there were significant spatial and ...