Coupling 3D hydraulic simulation and fish telemetry data to characterize the behavior of migrating smolts approaching a bypass

• Published in: Journal of Ecohydraulics
• Main Authors: Ben Jebria, Noor, Carmigniani, Rémi, Arthur, Drouineau, Hilaire, de Oliveira, Eric, Tétard, Stéphane, Capra, Hervé
• Other Authors: Laboratoire National d’Hydraulique et Environnement (EDF R&D LNHE), EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), École des Ponts ParisTech (ENPC), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Laboratoire d'Hydraulique Saint-Venant / Saint-Venant laboratory for Hydraulics (LHSV), École des Ponts ParisTech (ENPC)-Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema)-EDF R&D (EDF R&D), Ecosystèmes aquatiques et changements globaux (UR EABX), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Pôle OFB-INRAE-Institut Agro-UPPA pour la gestion des migrateurs amphihalins dans leur environnement (MIAME), Université de Pau et des Pays de l'Adour (UPPA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Office français de la biodiversité (OFB)-Institut Agro Rennes Angers, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), RiverLy - Fonctionnement des hydrosystèmes (RiverLy)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2023
• Subjects: Computational fluid dynamics; Salmo salar; fish behaviour; downstream migration; swim path; [SDV.EE]Life Sciences [q-bio]/Ecology; environment; [SDE.IE]Environmental Sciences/Environmental Engineering
• Online Access: https://hal.inrae.fr/hal-03368959; https://hal.inrae.fr/hal-03368959/document; https://hal.inrae.fr/hal-03368959/file/Drouineau-2023.pdf; https://doi.org/10.1080/24705357.2021.1978345

International audience Human-induced river fragmentation is a major threat to migratory fish species. Restoringriver connectivity requires the construction of fish passage solutions, such as fishways forupstream and downstream migration. While many studies focussed on the upstream migra-tion of diadromous fishes, and especially of adult Atlantic salmons (Salmosalar), we analyzejuvenile behaviour under different hydraulic conditions at reservoir to improve the develop-ment of effective bypass systems for downstream passage of salmon smolt.Based on coupling three-dimensional (3D) computational fluid dynamics (CFD) simulationsto smolt positions tracked by two-dimensional (2D) telemetry, the present study aimed toexplore smolt behaviour in relation to hydraulic cues. More specifically, we explored howhydraulic conditions influence fish behaviour and how fish navigate depending on thisbehaviour. In 2017, 23 smolts were tracked in the reservoir of Poutes (Allier River, France),associated with different turbine discharge rates. 3D CFD simulations were performed andvalidated against field measurements in the reservoir upstream of the hydropower plant.The study of fish displacements in relation to flow conditions provided new insights withthe use of thrust force, swimming orientation and direction as means to precisely character-ize smolt behaviour, which can help in the design of downstream migration passage facili-ties. At Poutes dam, flow velocity, flow acceleration and turbulent kinetic energy are verylow and therefore can lead to fish disorientation. However, results underlined that having aminimum flow velocity of 20cm/s in reservoirs is sufficient to prevent delay and allowfish navigation;