Fish Assemblage Structure and Environmental Correlates in Nepal’s West Rapti River, Banke

Abstract

The spatial and temporal variations of fish assemblages in rivers and streams of Nepal are poorly understood. So, the present study aimed to explore the spatial and temporal variations of fish assemblage structure in Nepal’s West Rapti River. The data were collected during autumn, winter and spring seasons, from October 2018 to April 2019. Fish samples were collected using cast net of 12 mm mesh size. A total of 28 species belonging to 7 orders, 10 families and 19 genera were recorded during the study. The analysis of similarity (ANOSIM) showed no significant difference among the stations and seasons. Based on cluster analysis, two major clusters were observed. The similarity percentage (SIMPER) analysis delineated that Cabdio morar (C14, 13.63%), Barilius bendelensis (C11, 10.32%), Gogangra viridescens (C22, 7.85%), Salmostoma phulo (C17, 7.74%), Labeo gonius (C5, 7.53%), Gagata cenia (C23, 6.45%), Garra gotyla (C6, 5.87%) and Labeo dyocelius (C2, 5.62%) were the most contributing species. The Canonical Correspondence Analysis (CCA) distinctly showed that the environmental variables dissolved oxygen, pH, carbon-dioxide, and water temperature play an essential role in shaping the fish assemblage structure of West Rapti River.

Correlation of fish assemblages with habitat and environmental variables in the Phewa Khola Stream of Mangsebung Rural Municipality, Ilam, Nepal

“…The most diverse order and family sampled were the Cypriniformes and Cyprinidae, respectively. This result is consistent with the findings of several previous studies (Shrestha et al, 2009;Mishra and Baniya, 2016;Shrestha, 2016;Subba et al, 2017;Yadav, 2017;Limbu et al, , 2019aLimbu and Gupta, 2019;Punam and Limbu, 2019;Chaudhary et al, 2020;Limbu and Prasad, 2020;Prasad et al, 2020) and the fact that the majority of freshwater fish are in the order Cypriniformes and family Cyprinidae (Nelson, 2006).…”

Fish Diversity and Water Quality Parameters of Mechi River, Jhapa, Province No. 1, Nepal

“…The results of this study showed that species of fishes belonging to order Cypriniformes were abundant during the winter season at station B, which lies at base of hilly area thus serves as overlapping niche for both warm and cold water fishes. This result matches with the findings by Edds (1986), Chaudhary et al (2020), and Limbu et al (2018aLimbu et al ( , 2018b, which might be due to the same elevation patterns of the rivers investigated and the similar water quality parameters of the rivers. The possible reason could be due to the availability of sufficient volume of water which is comparatively less disturbed as compared to other sites.…”