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Seasonal and diel changes in fish distribution in a tropical hydropower plant tailrace: evidence from hydroacoustic and gillnet sampling
Author(s) -
Loures R. C.,
Pompeu P. S.
Publication year - 2015
Publication title -
fisheries management and ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.693
H-Index - 55
eISSN - 1365-2400
pISSN - 0969-997X
DOI - 10.1111/fme.12116
Subject(s) - abundance (ecology) , nocturnal , hydropower , fishery , sampling (signal processing) , environmental science , diel vertical migration , dry season , fish <actinopterygii> , wet season , ecology , biology , filter (signal processing) , computer science , computer vision
Hydropower plant operation can lead to direct impacts on fish near the dam, causing injuries and death. In B razil, it is more common to observe these impacts in the tailrace. To understand temporal and spatial variations in fish abundance in the tailrace, to assist plant operation management, surveys were performed in T rês M arias H ydropower P lant using hydroacoustics and multimesh gillnets. Data were collected in the tailrace backwater over 1 year, during 18 field trips, each covering a 24‐h cycle with six sampling intervals. A greater abundance of fish was found in the tailrace during the wet season, mainly explained by total discharge. More fish were detected by hydroacoustics and gill nets during night sampling. Siluriformes, which are known to exhibit nocturnal habits, were the predominant species in both dry and wet seasons. Thus, damaging operational procedures for fish should be planned in the dry season, low‐abundance period.