Community-Based Stock Enhancement and Fisheries Management of the Japanese Flounder in Fukushima, Japan

Abstract

In Fukushima Prefecture, one million hatchery-reared juvenile Japanese flounder Paralichthys olivaceus have been released annually in the stock enhancement program since 1996. A community-based management system is used for this flounder fishery, where fishers pay 5% of their annual landings to operate the stock enhancement program. Also, since 1993, fishers have consented not to catch flounder < 30 cm total length to maximize economic gains from the investment in stock enhancement. Our fish market surveys revealed that released flounder annually contributed an additional 30–90 tons to the catch. However, the economic efficiency of stocking has reduced since 1996, which has been largely attributed to a decline in fish price and recapture rate. Another problem is that the population dynamics of wild flounder have never been considered during implementation of the stock enhancement program. The occurrence of a dominant year-class of wild flounder causes a dramatic increase in landings and removes the need to release hatchery-reared juveniles. However, the program cannot be easily terminated because it plays important roles in having fishers recognize the importance of fishery management. It is a difficult but important realistic problem concerning how to make the stock enhancement program more flexible and effective.

Keywords:

• community-based system
• dominant year-class
• Japanese flounder
• stocking effectiveness
• wild population dynamics

ACKNOWLEDGMENTS

We are greatly appreciative to Shuichi Kitada for the encouragement to write this manuscript. We thank the staff of Fukushima Prefectural Fisheries Experimental Station for their help in fish market surveys. We also thank the staff of Ishikawa-Seisho-maru for their support in the collection of wild juvenile flounder.

Notes

*Landed value divided by the cost of seed production (see text).