A case study of the phenotypic variations in barilius bendelisis (Hamilton) from a Perennial stream and a fish pond of Garhwal Himalayan region of Uttarakhand, India

Abstract

A comparative study on the morphometric and meristic variables of Barilius ben-delisis (Ham.) from two different water bodies, i.e., Khanda Gad, a perennial spring fed stream and fish pond in the Garhwal Himalayan region of Uttarakhand was made during the present study. A total of 100 specimens were analysed for 26 different morphometric variables and 14 meristic counts. All morphometric variables showed linear relationship when expressed in relation to total length and head length (except for caudal length in Khanda Gad’s fishes). As observed by meristic counts for different length of fishes, it remained constant with increasing body length. Standard length was found to be the highly correlated character in samples from both sites. Principal Component Analysis of 10 significant morphometric variables yielded three compo-nents accounting for 73.38% of the total variation. Principal Component Analysis of 3 meristic variables yielded single component accounting for 62.3% of total variation. Principal Component Analysis plots show that characters like, base of caudal fin, least height of caudal peduncle, pre-orbital distance, post-orbital distance, eye diameter, inter orbital distance, numbers of dorsal fin ray, scales from lateral line to pelvic fin and scales from lateral line to anal fin distinguishes the fish stock from fish pond and Kanda Gad. Discriminant Function Analysis for morphometric and meristic variables showed that 98% and 83% of individuals were allocated into their original populations respectively. The cluster analysis for morphometric characters showed of fish populations from both sites formed two major clades, thus significantly differentiating the two stocks of fish population. These morphometric variations could be attributed to the difference in the ecological and the rearing condition of fish stock from the stream and pond. The information on phenotypic variation between the natural stream and hatchery reared fish would be important for development of aquaculture.