Recently, the total yield of the scallop Patinopecten yessoensis cultivation has amounted to more than 80 thousand tons at the Oshima substation in Hokkaido. The price of the cultivated scallop has been declining because of an increase in the yield and hence its cultivation is in a critical condition. In order to overcome this, this paper shows that the total yield must be decreased to the optimum one proposed here. In addition, we allocate the optimum total yield to the Oshamanbe, Yakumocho, Otoshibe, Mori and Sahara fishery cooperative associations, using three methods of allocation under the cooperative game. We recommend the CG principle, which is one of the three allocation methods under the cooperative game, for the following reason. If the optimum total yield is less than a certain level, the allocated amount is the same, independent of the vested rights in the CG principle. If the optimum total yield is more than a certain level, the allocated amount is proportional to the vested rights. If the optimum total yield is between the two levels, the allocated amount is not proportional to the vested rights and is not independent of the vested rights.
