Study on species composition and abundance of pelagic fishes in flooding season in An Giang province

Abstract

Study on fish compositon and abundance of pelagic fishes in flood season was conducted for 6 months from June to November, 2022 in An Giang province. The fish samples were collected by using bag net in river/canal and long fence trap in rice field. The river water level rises from June and reaches its peak from October to November. The results showed that 42 species belonging to 13 families and 6 orders were identified. The most abundance oder containing 23 species (54.76%) was Cypriniformes, followed by Siluriformes with 12 species (28.57%). Cyprinidae was the highest number of species with 20 spcies (47.62%), followed by Pangasiidae with 6 species (14.29%). Beside that, the distribution of species variation based on different habitats and times. A total of 39 species were recorded in rivers/canals (92.8%), while 33 species were identified in filed (78.5%). The lowest number of fish species recorded in both water bodies in June with 22 species and the highest number of fish species were collected in October with 33 species. The results also indicated that catch per unit effort (CPUE) was relatively low and fluctuated through the sampling sites and times. CPUE increased from June (0.00199 kg/m3 in river/canal and CPUE = 1.5kg/day/net in the rice field) to October (0.0027 kg/m3 in the river and 6.5kg/gear/day in the rice field). Some of high value fish such as Henicorhynchus siamensis, Cirrhinus jullieni, Syncrossus helodes, Yasuhikotakia modesta, Pangasianodon hypophthalmus, Pangasius bocourti were captured and kept for culturing to increasing value.