Bull. Jpn. Soc. Fish. Oceanogr. 74(sp), Page 90-93, 2010   Considerations of reproductive characteristics for fisheries management Akihiko Yatsu National Research Institute of Fisheries Science, Fisheries Research Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan e-mail: yatsua@fra.affrc.go.jp Among reproductive characteristics of commercially exploited fishes, only age at maturity is currently taken into account in calculating spawning stock biomass (SSB), which is one of the standard biological reference points in the traditional single-species fisheries management. Recent studies on the Atlantic cod and fishes in the California Current suggested importance of diversity in age structure of spawners, and fishing would elevate stock variability under fluctuating environmental conditions, mainly through “longevity overfishing”. Therefore, in addition to SSB, conservations of biodiversity including age compositions, local sub-stocks and reproductive characteristics of spawners, coupled with marine protected areas, are necessary for a robust management. This can be viewed within a framework of the Ecosystem Approach to Fisheries. Key words: fisheries management, age structure, maternal effects, biodiversity, ecosystem approach