The fish assemblage and diversity in relation to water quality of three coastal rivers Sita, Swarna and Varahi of Udupi district, Karnataka, India was studied.71 species representing 7 orders, 20 families and 41 genera were recorded from 21 sites along the three rivers.Species composition varied longitudinally in relation gotrax handlebar to the environmental factors of the habitat.The downstream change in the three aptamil allerpro rivers indicates that fish assemblage changed with increasing loss of riparian canopy cover and increasing agricultural land-use.
The richness and abundance of fishes were correlated with land-use type, canopy cover, pH and turbidity.Diversion of water, discharge of domestic sewage and agricultural runoff were prominent among the disturbances that alter the habitat quality.