Distribution pattern, endemism, threat status and conservation measures of fishes in the Tunga and Bhadra rivers of Western Ghats, India

This study documents the distribution patterns, endemism and uniqueness (species richness) of fishes in the Tunga and Bhadra rivers of Western Ghats, India. We recorded 77 species represented by 7 orders, 16 families and 44 genera, of which 36 species are endemic to Western Ghats, 12 species endemic to India and 26 species endemic to the Indian Subcontinent. Based on our analysis on the distribution patterns, the Tunga River is richer in diversity and higher in endemism than the Bhadra. We calculated the similarity of the species composition among sites within these two rivers using the Jacquard index. The similarity index between the sampling sites of these rivers revealed that the similarity decreases with increasing distance between the sampling sites. Of the 77 fish species we collected, 8 species (11.1%) are in the Critical category, 10 species (13.8%) are in the High Risk category, 36 species (50%) are in the Moderate category and the remaining 18 species (25%) are at lower risk. The threat status of fishes found in the Tunga and Bhadra rivers strongly suggests the need for effective conservation measures to conserve the fish species richness of these rivers.