[ABNJ Ocean Partnerships] Current Knowledge, Key Uncertainties and Future Research Directions for Defining the Stock Structure of Skipjack, Yellowfin, Bigeye and South Pacific Albacore Tunas in the Pacific Ocean (Workshop Report)
Tuna are the focus of significant fisheries in the Pacific Ocean, with landings of four species (skipjack tuna, yellowfin tuna, bigeye tuna and albacore tuna) constituting approximately 70% of the global tuna catch. Stock assessments for skipjack, yellowfin, bigeye and South Pacific albacore tunas in the Pacific Ocean currently assume eastern and western stocks, a split that reflects historical development of fishery management in the region rather than biological considerations. There is widespread agreement that uncertainties surrounding the stock structure of the four main target species could have important impacts on population dynamics models used to assess stock status and inform management options. Improved knowledge of stock structure is also essential to modelling the effects of climate change on the distribution and abundance of tuna species. This paper reviews current knowledge and understanding of the stock structure of skipjack, yellowfin, bigeye and South Pacific albacore tunas in the Pacific Ocean, through an exploration of available literature relating to movement, connectivity, and spatial dynamics. Informed by an expert workshop, key questions were outlined that need to be addressed to determine the stock structure for each species, and propose some potential sampling designs by which future studies may address these uncertainties and improve understanding of stock structure of the four tuna species in the Pacific.
[ABNJ Ocean Partnerships] Current Knowledge, Key Uncertainties and Future Research Directions for Defining the Stock Structure of Skipjack, Yellowfin, Bigeye and South Pacific Albacore Tunas in the Pacific Ocean (Workshop Report).pdf
