Standardization of albacore CPUE by Japanese longline fishery in the Indian Ocean

Standardization of albacore CPUE by Japanese longline fishery in the Indian Ocean was conducted using the Generalized Linear Model (GLM) with lognormal or delta lognormal error structure. Cluster analysis was conducted before standardization, and cluster number was used for main effect as well as year, quarter, vessel ID and five degree latitude/longitude block and several interactions. Area definition is the same as that for 2019 IOTC albacore stock assessment. CPUEs slightly increased from early 1990s to early 2010s, and the trend was different among areas after that. The trend of CPUE was usually similar to that in the previous study.