The Min River Estuary and its adjacent waters, connecting to the East China Sea, is one of the most important fishing grounds in Fujian Province, southern China; however, stock assessments have not yet been conducted. In the present study, the length-based Bayesian estimation method was applied for the first time to assess 20 single-species fishery stocks in the region. Catches of eight fish species from the Class Actinopterygii and 12 shrimp species from the Class Malacostraca were obtained from two commercial demersal trawlers, operated in the Min River Estuary and its adjacent waters, in February, May, August, and November of 2017 and 2018, covering all four seasons. The results showed that eight species were overexploited with an estimated B/B MSY (i.e., the current exploited biomass relative to the biomass producing the maximum sustainable yield) < 0.8 (range from 0.26 to 0.71). Three overexploited fish species (Gray's grenadier anchovy Coilia grayii, the big head croaker Collichthys lucidus, and the Trevavas croaker Johnius trewavasae) are commercially important food species in the region. All four overexploited shrimp species (the shrimp Parapenaeopsis cultrirostris, the Japanese snapping shrimp Alpehus japonicus, and the Caridean shrimps Palaemon annandalei and Palaemon carinicouda) are small-sized and have low commercial value. The threelined tongue sole Cynoglossus abbreviates, a commercially important species, was classified as fully exploited (0.8 ≤ B/B MSY ≤ 1.2). Osbeck's grenadier anchovy Coilia mystus and the Japanese mantis shrimp Oratosquilla oratoria, both commercially important food species in the region, had non-fully exploited statuses (B/B MSY > 1.2). The results revealed that some commercially important food fishes are overexploited in the region and that small-sized, non-commercial food species can also be overexploited. There is an urgent need for local and national fisheries authorities to focus on coastal fishery management.

The CMSY and Bayesian Schaefer model (BSM) methods were applied to assess datalimited fishery stocks in the Japan Sea and surrounding areas of the Northwest Pacific. Ten stocks including 4 fish species and 5 cephalopod species were assessed; the CMSY method was used in 3 stocks with catch data only, and the BSM method in 7 stocks with both catch time series and catch per unit effort (CPUE) data available. The two methods estimated the maximum intrinsic rate of population increase (r) and carrying capacity of each stock, which allowed the computation of maximum sustainable yield (MSY), and exploited biomass relative to the biomass at maximum sustainable yield (B/B MSY ). All 10 stocks were overfished, if to a different extent, and one, the spear squid (Heterololigo bleekeri) has collapsed. The reference points estimated here may be used as indicator for fishery management in this ecoregion.

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