CPUE standardization of Pacific saury (Cololabis saira) for the Chinese Taipei’s stick-held dip net fishery in the Northwestern Pacific Ocean from 2001-2018

The catch and effort data of Pacific saury for the Chinese Taipei’s stick-held dip net fishery in the Northwestern Pacific Ocean were collected from 2001 - 2018. Two alternative approaches, generalized linear models (GLMs) and generalized additive models (GAMs), were applied to standardize the catch per unit effort (CPUE) of Pacific saury, with an assumption of lognormal error distribution. In this study an updated version (incorporating 2018 data) of the previous year’s CPUE standardization data set derived from fishing logbooks was used. Most of the main explanatory variables and interaction terms used in the modeling analyses were statistically significant. The results derived from both approaches, GLMs and GAMs, were almost identical. Standardized CPUE of Pacific saury for the Chinese Taipei’s stick-held dip net fishery in the Northwestern Pacific Ocean showed a general oscillating trend with a slight increase observed from 2001 - 2010, followed by a sharp increase through to 2014, a sharp decline until 2017, and then a dramatic increase in 2018.