Status (1993-1994) of the Endangered Fish Himalayan Mahseer Tor putitora (Hamilton) (Cyprinidae) in the Mountain Reaches of the River Ganga

Abstract

The status of Himalayan mahseer was assessed during 1993-94 in the foothill section of river Ganga and the upstream tributary Nayar where brooders migrate from the Ganga to spawn during peak monsoon. Fishes measured to range from 14.5 to 98 cm, comprised 1+ to 9+ age groups in the foothill section of river Ganga while the largest fish of 128 cm (13+) was recorded from the Nayar. Males beyond 5+ age groups were rare. Lower age classes 2 to 4+ comprising immature and maturing stages accounted for more than 70% of total popula-tion. Observations on the oocyte growth revealed only maturing individuals (IIIrd stage of maturity) in the river Ganga and sexually mature from the river Nayar suggesting matura-tion during ascending migration (February-June). The sex ratio was male oriented in the lower age classes and female predominance in the higher age classes. Mahseer accounted for only 10-15% of total fish catch in the foothill section, compared with 29.44% in 1978 (Jammu) 39.2% in 1964 (Himachal), 40.5% in early 80's (Kumaun Lakes) and 63% in 1969 (Gobindsagar reservoir).