An Estimation of Fish Biomass and Attached Organisms beneath Oyster Rafts in Hiroshima Bay, Japan

Hiroshima Bays is top production approximately 60% of oyster in Japan. For cultivate oyster, fishermen use hanging rafts. A thousand raft during 2-3 years the bay. Large-scale culture may change ecosystem structure and material cycles bay through filtration particulate matter by oysters other associated animals. This study described community marine organisme terms fishes surrounding animal attached on Field observation was carried out from 2016 to 2019 at farming Bay. Oyster provisioning for fish habitat were also evaluated placing underwater video cameras beneath The result showed that black seabream high biomass it shelf bigger bioyster raft. number individual, mussel most abundance attach with ratio 9:1 than oyster. Maintaining important not only maintaining production, but enhancing paths food chains Bay under oligotrophic conditions.