Abstract
We developed a population model considering the biological characteristics of Aetobatus flagellum, for the conservation of bivalves and the reduction of ecological damage to Ariake Bay. On the basis of the numerical model developed, we studied an effective method of A. flagellum extermination and calculated the impact of carrying it out in the bay to reduce predation damage to bivalves. The populations of A. flagellum calculated using the model were in agreement with those observed by field study. The calculation result of current A. flagellum extermination projects being performed from June to October revealed that more than 40% of the damaged bivalves were reduced as compared with the amount when extermination had not been performed. In addition, our model revealed that the reduction in the population of damaged bivalves could be more effective if the extermination is carried out in the northern head area of Ariake Bay, within Fukuoka and Saga Prefectures, during the spawning season in June and July.
