Stock assessment of Neon flying squid in the Northwest Pacific using JABBA model up to 2024
This study provides an updated stock assessment for two seasonal cohorts (winter-spring and autumn) and the stock-wide population through 2024, using JABBA (Just Another Bayesian Biomass Assessment). Abundance indices were derived from the Chinese squid-jigging fishery, including nominal CPUE, GAM-standardized CPUE, and RF-standardized CPUE. Annual catch data were obtained from the official NPFC compilation “NPFC-2025-AR-Annual Summary Footprint - Squids”, aggregating reported catches from all members. A total of nine assessment scenarios were conducted, covering three stock units × three abundance indices. The scenario based on RF-standardized CPUE for the stock-wide population was designated as the base case. All models converged successfully, and residual diagnostics confirmed satisfactory model fit. Retrospective analysis showed negligible bias (Mohn’s ρ < 0.1). The results consistently indicated that in 2024, none of the stock units were overfished (B/BMSY > 1) and overfishing was not occurring (F/FMSY ≤ 1). Short-term projections further confirmed the stock’s resilience to catch levels within the recent historical range. These findings provide a scientific basis for considering the current exploitation of neon flying squid as sustainable under the NPFC management framework.