Improving eel pass efficiency: The role of crest shape and water flow in facilitating upstream juvenile eel migration.

ABSTRACT: River connectivity is crucial for the European eel (Anguilla anguilla) to complete its complex life cycle, which is vital for upstream recruitment to the declining population of this critically endangered catadromous fish. Eel passes, or ladders, are frequently installed on riverine structures, such as dams and weirs, to mitigate barrier effects and restore connectivity for upstream migrating eel. Efforts to optimise the effectiveness of passes have previously focused on the ascent section, quantifying the effects of climbing substrate, longitudinal slope, lateral slope and flow rate. However, conditions at the pass crest also impact the rapidity and success of upstream movements. Using controlled experiments and custom-built eel passes with contrasting crest shapes (curved vs. sloped) and

SUBMITTER: Williamson MJ 

PROVIDER: S-EPMC12360135 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature