Food is an important factor in the biology of fishes, which governing their growth, feeding and migratory movements. The basic function of an organism is growth, development and reproduction andit takes place at the expense of energy which enters the organism in the form of its food. The present study aims on diet composition and feeding dynamics of Bombayduck, Harpodonnehereus along Sunderban area by employing ‘points method’ for an one year duration from August, 2008 to July, 2009. Non- penaeid prawns are the main food item, contributing maximum percentage were noticed during the November (54.80%) and lowest during the August (20.90%). Juveniles of Bombay duck formed the second important gut content of Harpodonnehereus, which indicates the cannibalistic feeding behavior. The percentage of Bombay duck juveniles ranged from 15.49% (November) to 41.63% (May). Small pelagic fishes recorded in gut contents ranged from 7.70% (October) to 24.29% (February) mainly Coiliadussumieri. Plant matter,zooplankton, sand and mud and miscellaneous items are also noticed in guts, but they are less quantities when compare to previous food items. Non penaeid prawns are the major diet for the Bombayduck fisheries. So, based on the shoalsofnon penaeidprawns, Bombay duck migrations can be traced out. The proximate composition of fish varies with feeding conditions and levels of food supply, reported changes in proportion to muscle biochemical constituents viz., protein, lipid, ash, moisture and energy contents were examined group wise i.e.immature and mature group. Proximate composition values of Harpodonnehereus was found to bemoisture 86.72%, protein 7.10%, fat 1.73% and ash 1.48% for immature group & 88.64% of moisture, 7.43% of protein, 2.0% of fat and 1.52% of ash for mature group. In the present study, the mature fish group exhibited relatively more values in terms ofbiochemical constituents than immature group. It might be due to fundamental nitrogen required for maturation, high lipids and proteins are required for liver during pre-spawning stage.
