CPUE standardization of Neon flying squid caught by the Chinese squid jigging fishery up to 2022 in the Northwest Pacific Ocean

The catch per unit effort (CPUE) of a species is an important proxy for fish abundance and is influenced by a number of factors, including environmental variables. The effects of these factors may alter the assumed proportionality between observed CPUE and stock abundance. Predicting accurate CPUE assists managers in assessing the status and trends of O.bartramii. Based on the neon flying squid fisheries data in the Northwest Pacific Ocean squid fishery from the Chinese mainland, generalized additive model (GAM) and Xtreme gradient boosting model (XGB) were used to standardize CPUE of O.bartramii for Chinese squid-jigging fishery. We used the variance inflation factors (VIF) to screen out the factors with low multicollinearity. The performance differed between models and cohorts. The performance of the XGB is better than that of the GAM. The trends for the nominal CPUE and the standardized CPUEs were generally consistent with each other, and the standardized CPUEs are more stable than the nominal CPUE for the two cohorts.