Updated information on catch and effort of yellowfin tuna (Thunnus albacares) from Indonesian tuna longline fishery

Yellowfin tuna (Thunnus albacares) is one of the main targets for Indonesian tuna longline fishery in the Eastern Indian Ocean. There were two types of data used in this study; first was the skipper’s “logbook” data from the state-owned commercial tuna longline vessels based in Benoa Port (1978-1995), and the later was the scientific observer data conducted by Research Institute for Tuna Fisheries (RITF) from 2005 to 2018. Both data then combined to produce nominal catch per unit of effort (CPUE) (no. fish/100 hooks). The result showed that the catch rates of yellowfin tuna is declining over the years. The highest CPUE recorded was in 1982 (0.94), while the lowest was in 2015 (0.03). Efforts distributed mainly within 0-35 oS and 75 – 130 oE. While high average CPUE areas mainly occurred between 5-10 oS and 80-130 oE. We are still in progress of completing the skipper’s “logbook” data entry in a hope of presenting the appropriate yellowfin tuna standardized CPUE in the future.