Corresponding Author Affiliation*:  Northwestern University, Vietnam

Abstract:

Son La Hydroelectric dam is the largest hydroelectric work in the South East in the upstream of Da River at It Ong Commune, Muong La District, Son La, Vietnam. This is the multi-objective work with great role for national power production and economic development, water regulation for Red River Delta. However, the construction of Son La Hydroelectric dam has drastically reduced the diversity of fish species here. Pursuant to the data comparison and analysis from previous researches and result of field surveys in 2019 and 2020, the research indicated clearly the effects of the construction and operation of hydroelectric dam to the diversity of fresh – water fishes in Son La Hydroelectric dam. The result showed that the composition of fresh-water fishes here has decreased by 30% compared to before the construction of hydroelectric dam. The current composition of fish species in this area is identified as 69 species and 1 subspecies belonging to 20 families, 9 orders and showing a high degree of diversity in both order and family level. In this area, 53 species are listed in IUCN Red List, 6 species in VU Vulnerable, 2 species in NT Near-threatened, 26 species in LC Least Concern, 19 species in DD Data Deficient. In particular, the research added Truong Giang Drift fish (Prochilodus argenteus Spix & Agassiz, 829) and channel catfish (Ictalurus punctatus Rafinesque, 1818) to the list of Da River fish in Son La area. This is the first research on the composition of fish species in Son La Hydroelectric dam after the construction and coming into operation in 2012. Through the research, we proposed measures to preserve the diversity of composition of fresh-water fish species in the research area.

Keywords: Son La Hydroelectric Dam, Da River, Composition of Fish Species

DOI: https://doi.org/10.37227/IJEKM-2021-05-928