Assessment of health condition of the Pacific oyster Crassostrea gigas in an oil spilled area

Abstract

To assess environmental restoration and oyster productivity in an oil spilled area,we monitored the growth and physiological condition of Pacific oyster raised in asuspended long-line facility at Uihangri beach in Taean, one of the major areasdamaged by the Hebei spirit oil spill. Physiological condition was assessed usinghistology, biochemical composition analysis, and measuring reproductive effort. InDecember 2012, 15 months after placement, oysters grew 5.6 cm in shell length, 17.4 gin total weight, and 3.4 g in tissue dry weight. An enzyme-linked immunosorbent assayused to quantify egg biomass revealed that the fully ripe oysters produced a relativelysmall quality of eggs (22.9 %) of their body weight compared with adult oysters (40%),indicating that the 1-year-old oysters used in this study did not sexually mature. Thelow total carbohydrate and glycogen reserve in oyster tissue recorded in Septembercoincided with intense energy utilization due to spawning. The physiological condition ofcultured oysters was relatively better than wild oysters. In this study, we could confirmthe possibility of restoring oyster productivity in the oil spilled area by the suspendedculture system, although continuous monitoring should be carried out.r areasdamaged by the Hebei spirit oil spill. Physiological condition was assessed usinghistology, biochemical composition analysis, and measuring reproductive effort. InDecember 2012, 15 months after placement, oysters grew 5.6 cm in shell length, 17.4 gin total weight, and 3.4 g in tissue dry weight. An enzyme-linked immunosorbent assayused to quantify egg biomass revealed that the fully ripe oysters produced a relativelysmall quality of eggs (22.9 %) of their body weight compared with adult oysters (40%),indicating that the 1-year-old oysters used in this study did not sexually mature. Thelow total carbohydrate and glycogen reserve in oyster tissue recorded in Septembercoincided with intense energy utilization due to spawning. The physiological condition ofcultured oysters was relatively better than wild oysters. In this study, we could confirmthe possibility of restoring oyster productivity in the oil spilled area by the suspendedculture system, although continuous monitoring should be carried out.