Updated information on catch and effort of albacore tuna (Thunnus alalunga) from Indonesian tuna longline fishery

Albacore tuna (Thunnus alalunga) is one of the main targets for Indonesian tuna longline fishery in the Eastern Indian Ocean. The fishery has begun since early 1980’s, when deep longline introduced. 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 2017. Both then combined to produce nominal catch-per-unit-of-effort (CPUE) (no. fish/100 hooks). The result showed that the catch rates of albacore tuna was very low at the start of the series (1978-1995) which below 0.2/100 hooks, but higher at the recent decade (2005-2017), which around 0.2-0.4/100 hooks. Efforts were geographically distributed within the area bordered by 5 – 35oS and 75 – 130oE.  High CPUE mainly occurred in sub area between 25oS and 35oS. We are still in progress of completing the skipper’s “logbook” data entry in a hope of presenting the appropriate standardized CPUE in the future.