Polyculture of seabass with tilapia for the utilization of brown fields in the coastal areas of Cox's Bazar, Bangladesh

Abstract

Disease outbreak in shrimp culture sector has abandoned the vast coastal areas of Bangladesh. These abandoned areas treated as ‘brown fields’ could be utilized for finfish culture using low cost inputs. This type of culture practice has the potential to be successful in the coastal waters due to having seasonally fluctuating salinity of 0 to 15 ppt. The present study was conducted to determine the growth and survival of seabass (Lates calcarifer) and tilapia (Oreochromis niloticus) using different stocking ratios without giving any supplementary feed to seabass. Tilapia was stocked at 1 individual/m2. Tilapia fry was expected to provide food for seabass in the selected culture ponds. The stocking ratio of tilapia and seabass were 4:1, 5:1 and 6:1 in ponds with three replicates for each treatment. During 3 months culture period, the highest harvest weight of seabass and tilapia was recorded as 74.3 and 49.1 g/m2, respectively and the highest survival rate of seabass and tilapia was recorded as 78.3 and 61.9%, respectively. The highest growth rate of seabass was recorded as 14.67 g/day and the highest biomass of seabass and tilapia (collectively) was found as 116.9 g/m2. The present study reveals that seabass-tilapia polyculture may be a good solution to utilize the coastal brown fields of Cox’s Bazar, Bangladesh. Key words: Polyculture, seabass (Lates calcarifer), tilapia (Oreochromis niloticus), brown fields.