Length-Weight Relationship, Condition Factor and Stomach Content Analysis of Eutropiichthys murias (Hamilton,1822) from Narayani River, West Nawalparasi, Nepal

Abstract

Eutropiichthys murius is the major fish of the riverine ecosystems in Narayani River. The primary goal of this study is to investigate the length-weight relationship, condition factor, and stomach content analysis of Eutropiichthys murius. A total of 200 fish samples were collected seasonally from June 2022 to November 2022 with the help of local fishermen by the using cast and hook net. The overall length ranged from 8.5 cm to 39.2 cm, with weights ranging from 7.4g to 395.6g. For the Summer and Autumn seasons, the length-weight relationship was W= 0.218 x TL 2.607 (R 2 = 0.879) and W = 0.0096 x TL 2.960 (R 2 = 0.9105), respectively, indicating a negative allometric growth pattern in E. murius. In E. murius, the values of b for the summer and autumn seasons were 2.607 and 2.960, respectively, indicating a negative allometric growth pattern. The length and weight of this fish did not significantly correlate with one another in two seasons. The condition factor (K) range between 0.33 to 3.06 with mean value 0.77 indicated that the river’s fish population was not prospering. From the total number (200) of fishes, 138 (69%) stomach were observed with food and remaining 62 (31%) were empty. Insects, aquatic plants, and detritus constitute the majority of the food items found in the stomach of the fish. Polyrhachis spp, Acridida spp, Caribidi spp, Leptocorisa spp, Stipa tenacissima, Hydrilla verticella, water beetles, zooplanktons, miscellaneous items and non-biotic matters constitute the majority of this fish’s basic diet. In conclusion, E. murius was omnivorous and displayed negative allometric growth.