Skewed Sex Ratio Induced Imperilment of Himalayan Golden Mahseer Tor putitora: A Bottleneck for Captive Propagation

Getting sufficient number of female Tor putitora in wild or in captive conditions is a bottleneck for its sustainable management. In this study, presence of 84.62% male and 15.38% female in the riverine environment was observed while 85.25% male and 14.75% female were found in the lacustrine environment. There was 78.12% male and 21.88% female population in the hatchery produced siblings. Further, T. putitora fry (30 dpf) when treated with 17β estradiol (150 mg/kg feed) for 30 days resulted into production of 69.5% female while rearing it at 23 ±1 °C without any other treatment brought about 41.5% females. The skewed sex-ratio and low female populations of T. putitora has been understood to be an important factor for the imperilment of Himalayan golden mahseer and its propagation in captivity.