Economic evaluations of introducing the direct sales of oysters Crassostrea gigas with shells in Miyagi Prefecture

Abstract

The direct sales of oysters Crassostrea gigas with shells reduces the burden of shucked oysters. It is also expected to improve management as a result of high profitability and the reduction of the physical burden on fishermen and employees. This study used the Net Present Value (NPV) method to identify the production volume of the direct sales of oysters with shells after Miyagi oyster fishermen invested in an oyster washing machine, which should be sold to secure profitability. The production of oysters with shells amounts to 23,300 kg annually. The results show that the amount of direct sales of oysters with shells must be more than 4,600 kg. In other words, it is necessary for the fishermen to sell oysters with shells at an average of about 117 boxes (4.4 kg/box) a month in nine months. Therefore, it is important for oyster fishermen to mainly ship shucked oysters as a conventional practice, before acquiring new customers for the direct sales of oysters with shells. Further, oyster fishermen should aim to reduce investment in oyster washing machines by making joint purchases.