Abstract
Introduction: The entry and accumulation of fish inside the suction tubes of hydroelectric power plants can pose risks to these animals. To protect ichthyofauna, repulsion systems employing diverse methodologies have been developed. Objective: The main objective of this study was to investigate the dissuasive effectiveness of a bubble and light barrier on ichthyofauna. Methodology: The experiment consisted of video recording in three stages, performed in triplicate: before activating the barrier, while the barrier was active, and after deactivating it. The movement of five juvenile Amazonian species (Cichlasoma amazonarum, Dianema urostriatum, Pimelodus blochii, Brycon spp., and Colossoma macropomum) was analyzed across the three stages by counting individuals in specific sectors every 15 s. A total of 30 specimens of each species were used, with 10 individuals allocated to each aquarium. Results: Barrier activation induced repulsion in Pimelodus blochii, Brycon spp., and Colossoma macropomum, but attraction in Cichlasoma amazonarum and Dianema urostriatum. The study reveals that the tested species respond dissimilarly to stimuli from the behavioral barrier. Conclusions: These findings address a research gap regarding native species′ responses to behavioral barriers. They underscore the importance of understanding regional ichthyofauna behavior for designing optimized bubble and light barrier systems to enhance method efficacy. The observed effectiveness highlights the potential of this robust, low-cost technology for ichthyofauna protection in hydroelectric plants.
Author Contributions
Conceptualization, M.V.d.M.N. and L.F.Z.; methodology, É.S.J.; software, M.A.B.; validation, É.S.J., M.A.B. and L.F.Z.; formal analysis, M.V.d.M.N., L.F.Z.; investigation, M.V.d.M.N.; resources, L.F.Z. and É.S.J.; data curation, M.V.d.M.N.; writing—original draft preparation, M.V.d.M.N., L.F.Z.; writing—review and editing, E.B.P.d.S. and M.V.d.M.N.; visualization, E.B.P.d.S.; supervision, L.F.Z.; project administration, M.V.d.M.N.; funding acquisition, L.F.Z. All authors have read and agreed to the published version of the manuscript.
Funding
This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001.
Institutional Review Board Statement
The animal study protocol was approved by the Research Ethics Committee of the National Institute for Amazonian Research (INPA) (protocol code no. 024/2021, SEI 01280.00912/2021-88 and approval date was 07/29/2021).
Informed Consent Statement
Not applicable.
Data Availability Statement
The data presented in this study are available on request from the corresponding author.
Conflicts of Interest
The authors declare no conflicts of interest.
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