Using LBB Tools to Assess Miter Squid Stock in the Northeastern South China Sea

Based on length frequency data of miter squid ( Uroteuthis chinensis ) collected in the northeastern South China Sea 1975–1977, 1997–1999, and 2018–2019, asymptotic length, optimal at first capture, relative mortality, biomass stock were estimated using length-based Bayesian estimation (LBB). The LBB-estimated for 2018–2019 was smaller. Optimal lengths capture later far exceeded average catches because a major increase fishing intensity. Between 1975 1977, total mortality Z / K low, but it increased latter two periods, while natural M showed downward trend. Relative biomasses B 0 msy indicated that close to unexploited between they declined levels 6% 4% which correspond growth horsepower. Indeed, by 2018, horsepower nearly four times level. analysis suggests has been overfished since mid-1980s is now under heavy pressure. To recover stock, imperative reduce intensity enforce size-at-first-capture regulations.