During the field visits, it was observed that the western river, Yenne Hole is mainly dominated with the native species (Refer Tables 7 and 8). Fishes like Cirhina reba and Labea jimbriatus dominate the fish catch supported by species like Ompak bimaculatus, and Mystus species. Tor species were found in Hallibylu region of the river system. Thus, generally in this locality, the season-wise species composition remains more or less the same. Further, the south western part again shows similar trends of Yenne Hole. But here the Tor species were not recorded during sampling. In both the cases, the natural terrain is a series of hills and in between the hills the valley. These valleys being shallow areas are excellent localities for the indigenous monsoon breeders and thus large number of such fishes can be found in this river system.

The deeper regions like Holebagilu, Hasaramakki and Medenur have major fish catch of introduced species during monsoon season. As the monsoon season ends the catch of introduced species reduces and indigenous species dominate. This condition prevails until there is water inflow into the reservoir due to rainfall. The checklist of the fishes of linganamakki reservoir with their geo­graphical distribution is given in Table 9 .