Yellowfin tuna is considered a single population in the western and central Pacific Ocean (WCPO) for stock assessment purposes (Vincent et al. 2020 and references cited therein), although there is still uncertainty about the stock structure along the Pacific Ocean.

The Parties to the Nauru Agreement (PNA) is an Oceania subregional agreement between the Federated States of Micronesia, Kiribati, Nauru, Palau, Papua New Guinea, Solomon Islands, Tuvatu, and the Marshall Islands. The PNA coordinates the implementation of management measures with a view to enhancing economic benefits from the fishery. Member countries of the PNA have adopted and implemented distinct Vessel Day Schemes for the longline and purse seine fisheries, whereby they allocate fishing days to a country which are sold to the highest bidder. The PNA unassociated (free school) fishery was MSC certified in 2011. All the PNA parties are Members of the WCPFC.

The Japanese tuna longline fishery includes an offshore fleet, distant water fleet and small coastal fleet. The distant and offshore longline fishery caught 6,915 t of yellowfin tuna in 2012, the small offshore longline fishery caught 2,157 t and coastal longline fishery caught 1,701 t of yellowfin tuna in 2012 {uosaki et al. 2013}.