Standardized CPUE of Chub mackerel (Scomber japonicas) caught by the China’s lighting purse seine fishery up to 2019

Chub mackerel (Scomber japonicas) is key economic and ecological specie in the Northwest Pacific Ocean. Most of the Chub mackerel catch is harvested by the lighting purse seine fishery in China. In this paper, we standardized catch per unit fishing effort (CPUE) using generalized linear model (GLM) and generalized additive model (GAM). Four groups of independent variables were considered in the CPUE standardization: spatial variables (latitude and longitude), temporal variables (year and month), vessel length and environmental variables (SST, SSH and Chl-a). Log-CPUE was treated as the dependent variable and its error was assumed to follow normal distribution in each model. The model selections of GLM and GAM were based on the BIC. From the results, Higher Spearman’s correlation and lower mean squared error were observed by GAM. Besides, the standardized CPUE trend of GAM model is similar with that of nominal CPUE. Therefore, we prefer to choose the best GAM model to estimated standardized CPUE of Chub mackerel fishery.