Food and feeding habits of threatened Notopterus notopterus in Gomti river, Lucknow (India)

Abstract

Food of the threatened Notoperus notopterus in Gomti river, Lucknow consisted mainly of shrimps, teleosts, insects and their larvae followed by items of lesser importance like plant matter, organic detritus and fish scales and diatoms, the percent composition of which varied during pre-monsoon, monsoon and post-monsoon period. An unusual feature observed was the occurrence of pebbles in stomach of 70% fish examined. When fluctuation in feeding activity of all the age groups viewed together, December recorded the maximum feeding while lower temperature of January appears to retard the rate of digestion, thereby declining appetite of the fish ultimately reducing food intake. The moderate temperature of February-April improves feeding, onset of breeding season (May-July) reduced it while the spent fishes resorted to vigorous feeding in the subsequent months which was reflected in constantly increasing gastrosomatic index value.