Silvercarp

Fisheries has an important role in agro-based economy of Bangladesh, contributing 63% of total animal protein intake. The population is increasing day by day and the total fish production is unable to cope up with it. Polyculture is a technique through which we get maximum out-put. It gives higher fish production than monoculture because of utilization of available natural food by fish in the pond. Silvercarp (Hypophthalmichthys molitrix) as an important species for polyculture because of its higher growth rate (Wahab et al., 1995) but the addition of this fish in mola-carp- tilapia polyculture has an impact on pond ecosystem. Again in case of silver carp, catla (Catla catla) and SIS polyculture, food competition and dietary overlap within of these species is expected. So, stocking ratio optimization of silver carp and catla in polyculture is needed to get the highest yield. Most researches in South Asian countries have focused on the biology and culture of Indian and Chinese carps, but a very few research has focused on stocking ratio optimization of these carps and their effects on pond ecology and small indigenous fish species.