Report of the Fifth IOTC CPUE Workshop on Longline Fisheries

A Workshop assessing CPUE trends and techniques used by the IOTC was held in Keelung from May 28th to June 1st, 2018. The aim of the meeting was to validate and improve the methods of collaborative CPUE analysis for tropical and temperate tuna species for main longline distant water fishing fleets operating in the Indian Ocean, to develop joint standardised CPUE indices for yellowfin and albacore tuna,  and to develop standardised indices for the national fleet, including Japanese, Taiwanese,  Korean, and Seychelles Longline fleet. A hands-on tutorial with a focus on the use of the generic R code was given covering all aspects of the joint analysis including the preparation of the data, descriptive analysis on catch and effort, the clustering analysis, and the CPUE standardizations for individual fleet. The 2018 Joint CPUE analysis included the data from the Japanese (1952-2017), Korean (1971-2017), Taiwanese (2005-2017), and Seychelles (2000-2016).