Deepali Rana, Ganesh Datt Bhatt
The study of fish diversity of Eastern and Western Doon Valley streams (2010-2012) viz., Baldi, Song and Suswa in East and Tons and Asan in West has revealed it to be represented by 56 species belonging to 5 Orders, 13 Families and 30 Genera. The present findings are the outcome of FactorAnalysis tool applied on 30 genera, fractionated into 2 categories viz., frequent (28 genera) and infrequent genera/species (2 genera + 12 species), with a view to find out determinants of associations amongst various genera. Four Factor groups (represented by 23 frequent genera + 1 set of infrequent genera/species) were obtained through oblique rotation of principal axes, factored from the number of individual’s data matrix of 480 collections, with heavy loadings of ≥ 0.70. The sake of convenience and easy understanding, various Factors have been named on the basis of genus/species showed the highest loading on each Factor. The distribution of fish genera according to their loading values in different Factors showed a specific pattern of association and vis-a-vis highlights meaningful interpretations about the ecological habitat characteristics of various genera.