Age and growth of red-spotted grouper Epinephelus akaara collected from the coastal waters of Toyama Prefecture were studied by observing transverse otolith sections. Opaque zones were confirmed to be annuli and mainly formed in August. The von Bertalanffy growth equation was estimated as: TLt = 507 (1–e-0.130(t+1.80)) for males and females, where TLt is the total length (mm) at t (year). This study is the first report of age and growth of red-spotted grouper in the Japan Sea. Our samples collected from Toyama Prefecture showed a lower growth rate than estimates from the Seto Inland Sea.
Using an online questionnaire, the membership qualifications for Japanese river fishery cooperatives were verified from data collected from 186 male respondents who wished to become cooperative members. Their responses showed that the legal conditions, comprising residential conditions and operating conditions, were greater limiting factors for joining the cooperatives than the cooperative conditions, made up of the payment contribution, paying expense, participation in fish enhancement, participation in fishery patrols, participation in cooperative meetings, and becoming a cooperative official. Between the two legal conditions, the operating conditions were a greater limiting factor than the residential conditions.