Feeding and reproductive biology of a freshwater catfish, Rita rita (Hamilton, 1822) from the river Ganga

Rita rita, a freshwater catfish from the Bagridae family is facing threats of extinction due to over-exploitation and the loss of breeding grounds owing to anthropogenically-driven ecological changes in their native habitat. River Ganga is one of the most important rivers of India, which is affected by industrial and urban waste disposal, unsanitary rituals, and other anthropogenic activities. Therefore, the present study was undertaken to assess the feeding and reproductive biology of R. rita which is native to India and Asian countries. A total of 260 R. rita samples were collected from the Narora site of River Ganga on a monthly basis. Data on feeding habits, feeding intensity, Gonadosomatic index, and maturity stages based on macroscopic and histological studies, fecundity, and sex- ratio were examined. The gut contents of R. rita were composed mainly of molluscs, fishes, insects, crustaceans, annelids, and detritus. RGLs varied significantly with fish size but stayed within the omnivore feeding category. From the month of May to July, females and males had higher GSI values. The fecundity of the sampled R. rita specimens ranged from 9464-72,678 in different size classes. Fecundity was found to be linearly related to body length, body weight, and ovarian weight. The average male-to-female ratio was found to be 1:2.6.