Review of fishery data used in the benchmark stock assessment for North Pacific shortfin mako in 2018

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This working paper reviews the fishery data used in the stock assessment for North Pacific shortfin mako, Isurus oxyrinchus, in 2018. The stock assessment was conducted using the Stock Synthesis 3 with three kinds of fishery data for 1975- 2016 which includes catch data, CPUE data, and size frequency data. Catch data comprises of annual catches of 18 fleets provided by four countries (Chinese Taipei, Japan, Mexico, and United States) and two Tuna-Regional Fisheries Management Organization (Western and Central Pacific Fisheries Commission, and Inter-American Tropical Tuna Commission). CPUE data comprises of annual abundance indices of 9 fleets and size frequency data comprises of 11 fleets provided by the above four countries. Finally, several recommendations are given for updating/revising the fishery data for the next stock assessment in 2024.