Cluster Management to Prevent Transmision of White Spot Syndrome Virusin Extensive Giant Tiger Shrimp Farming

White spot syndrome virus (WSSV) has become epidemic in Indonesia and affecting shrimp production lost in shrimp farm. Virus has transmitted from one to other ponds, mostly by crustacean, but more often transmit through water from affected pond. A cluster model, consist of two and three ponds surrounded by non-shrimp growing pond as biosecurity has developed. The model aim to prevent white spot virus transmission in giant shrimp extensive pond. The study was conducted in two sites at Demak district, Central Java province. Cluster consist of three shrimp ponds in site I, and cluster consist of two shrimp ponds, each surrounded by non-shrimp growing ponds. As control we also compare to 5 extensive shrimp ponds in site I and other three shrimp grow out ponds in site II, with neither no cluster system nor surrounded by non-shrimp pond as biosecurity. Result of the study shown that cluster of shrimp ponds surrounded by non-shrimp pond harvested at DOC 105,6±4,5 days significantly longer than that of control that harvested at 60,9±16,0 days because of outbreak, survival rate at 77,6±3,6 %, significantly higher than that of control at 22,6±15,8 % and shrimp production of 425,1±146,6 kg.ha^-1 significantly higher than that of control at 54,5±47,6 kg.ha^-1. These results suggest that implementation of Better Management Practices (BMP) by arranging shrimp ponds in cluster and surrounding by non-shrimp ponds proven effectively prevent WSSV transmission from traditional shrimp ponds in surrounding area.