08-April-2008 SEARCA RDD News Release
Growing a number of aquatic species, such as shrimp, milkfish, crab, and seaweed, in irrigated rice farms has long been widely adapted in many countries around the world. Farmer-adapters attest to their technical feasibility, economic attractiveness, and environment-friendliness. As such, farmers have always been on the lookout for new and improved variations of these integrated farming systems.
With SEARCA’s Seed Fund for Research and Training (SFRT) support in 2005-2006, a team of aquaculture scientists led by Dr. Tran Ngoc Hai of Cantho University in Vietnam simultaneously evaluated for the optimal stocking density of tilapia and shrimps in integrated rice farming systems, and measured changes in paddy water quality in Hong Dan district, Bac Lieu province.
The team found that water quality did not significantly differ across the treatments with different stocking density combinations of tilapia and shrimps. However, high stocking densities of either tilapia or shrimp reduced shrimp yields. The best stocking density combination of five shrimps and 0.25 tilapia per square meter gave the highest species yields of about 388 kg/ha of shrimps and 722 kg/ha of tilapia, and highest net income of about USD 282/ha/crop. As such, rice-based tilapia-shrimp polyculture show very promising results. (Bobbie Gerpacio, RDD)
