Multispecies fisheries management in Japan’s offshore waters: the case of Hokkaido Pacific offshore trawl

Abstract

Japan is currently implementing its reformed fisheries policy. The new Fisheries Act passed by the Diet in 2018 stipulates that output control through Total Allowable Catch (TAC) is the principle for fisheries resource management. This is a turning point for Japan, which has traditionally managed fish stocks primarily through input control and voluntary management by fishermen. TACs will be set to individual stocks using a harvest control rule, pre-determined through stakeholder dialogue. Japan lands a wide variety of fish and faces a difficult task of managing multispecies fisheries while balancing ecological, social, and economic objectives. This research aims to gain insight into the multispecies fisheries management under the new fisheries policy using a case study of the Hokkaido Pacific offshore trawl, which has a traditional Japanese-style co-management system and is scheduled to introduce TAC for cod. First, this study assessed the current co-management system using the Fishery Performance Indicator. The results showed that the fishery was performing high in the community aspect, especially regarding the "human" aspect, suggesting that Japan's co-management system can work effectively in the complex environment of a multispecies fishery and return the benefits to the local community. Meanwhile, the ecology and economy performed moderately. This study then simulated the effects of various harvest scenarios with a multispecies bioeconomic model. It revealed that achieving a stock recovery policy for decreased cod would lead to a significant socioeconomic loss. The new fisheries policy in Japan expects to improve ecological performance by strengthening the management of individual stocks. However, the key to success will be better understanding the impact of new management systems on fishermen's behavior and facilitating discussions with stakeholders by showing what would be improved and what risks are involved in not acting.