Study of habitat preference of Garra rufa in Dinorab River, Karkheh River basin

Since the selected habitat indexes provide a description of the habitat characteristics of a species, this study was conducted to investigate the habitat preference of Garra rufa in Dinorab River (Kermanshah Province), a tributary of the Karkheh River basin. For this purpose, the habitat characteristics, including water depth, water velocity, river width, potamal area width, predominant type of bedrock cover, pH, temperature, electrical conductivity (EC), total dissolved solids (TDS) were measured and recorded in 18 sub-stations belonging to six main stations from downstream to upstream. The used and selected habitat ranges were obtained according to the availability of each habitat unit for each variable. The results showed that the most preferred water depth is 26-30 m with a suitability index (SI) of 0.779, river width of 6-7.2 m with SI of 0.7, the water velocity 0.24-0.31 m/s with SI of 0.38, bed structure with medium diameter of 5-5.5 cm with SI of 1, water temperature 18-19 °C with SI of 0.618, pH 7.32-7.44 with SI of 0.545, EC 290-310 with SI of 0.767, TDS in the range of 580-610 ppm with SI of 0.712 and potamal width 4.8-6 with SI of 0.634. The results showed that the Dinorab River is a moderately suitable habitat for Garra rufa.