The PIRO International Fisheries Division provides policy advice on and technical and administrative support for, international fisheries agreements and related issues in the western and central Pacific Ocean (WCPO).

The need for international cooperation in fisheries management is driven by the highly migratory nature of many of the targeted and bycatch species and the exploitation of common resources outside areas of national jurisdiction, on the high seas. The high seas are regarded as global commons, accessible to anyone. With open access and no defined mechanism for regulating the use of the resources, the result can be overexploitation such as overfishing.

The term "highly migratory species" (HMS) derives from Article 64 of the United Nations Convention on the Law of the Sea Annex I to the Convention lists species considered highly migratory by parties to the Convention. In general, these species (such as tuna and billfish) have a wide geographic distribution, both on the high seas and inside the Exclusive Economic Zones (EEZ) of many nations, and undertake migrations of significant but variable distances. They are pelagic species, which means they do not live near the sea floor, and mostly live in the open ocean, although they may spend part of their life cycle in nearshore waters. These species are harvested by domestic and foreign fishing fleets. The U.S. accounts for a relatively small fraction of the HMS caught in the WCPO. Click here for a table of tuna catches in the WCPO by nation.

Many bycatch species of concern (e.g. various marine mammals, seabirds, sea turtles and sharks) possess similar attributes to target fish species, such as having wide geographic distribution and undertaking significant migrations.

The primary international regional fisheries management organization (RFMO) for HMS in this region is the Western and Central Pacific Fisheries Commission (WCPFC). Some Hawaii-based vessels also conduct limited fishing to the east of 150° west and therefore enter the area of competence of another RFMO, the Inter-American Tropical Tuna Commission (IATTC). The participation of the U.S. purse seine fleet operating in the western Pacific is governed by the Treaty on Fisheries Between the Governments of Certain Pacific Island States and the Government of the United States of America (South Pacific Tuna Treaty- SPTT), which provides for U.S. vessels to fish in the EEZs of certain Pacific Island countries.

Overfishing and habitat damage particularly from deep-sea trawling on the high seas is prompting the initiation of multilateral agreements to address this problem in the north and south Pacific Ocean. The South Pacific Regional Fisheries Management Organisation (SPRFMO) was created to manage resources in the South Pacific and adopted the Convention on the Conservation and Management of the High Seas Fishery Resources of the South Pacific Ocean in Auckland, New Zealand on 14 November 2009.

In 2006 delegations from Japan, Korea, Russia, and the United States, met in Tokyo to discuss the management of north western Pacific Ocean high seas bottom trawl fisheries. Participants recognized that creation of any formal arrangement would be a lengthy process and that, pending development of any such arrangement, more urgent action is needed in respect to these fisheries. They adopted revised interim measures in 2009 and agreed to continue discussions on this issue on an accelerated basis. The most recent meeting, which included discussion of a draft Convention, and included Japan, Korea, Russia, and the United States, as well as Canada, China, Chinese Taipei and Faroe Islands, was held in Yuzhno-Sakhalinsk, Russia in September 2010. The next meeting to discuss the draft Convention text is scheduled to be held in Vancouver, Canada in February 2011.

The American Samoa port sampling program has been collecting data and sampling fish at the canneries since the mid to early 1960s when the NMFS Honolulu Laboratory sent personnel down to sample and collect data from Asian longline vessels offloading at the canneries in Pago Pago. In 1980 a full time Port Sampler was hired by the Honolulu Lab to collect logsheets and sample Asian longliners, U.S. purse seine vessels, and troll (jigboat) vessels unloading to the two canneries. In the early years of the program, logsheets and sampling on vessels unloading at the canneries was strictly voluntary and vessels had the option of refusing to allow the port sampler to sample the fish and submit data. Although most vessels opted to sample their catch (fork lengths), logsheet collection was very sporadic and mainly consisted of obtaining general fishing area information. In June 1988, the SPTT was signed and data collection and length frequency sampling of the catch became mandatory for the U.S. purse seine fleet. In the early 1990s a fleet of U.S. longline vessels began fishing in American Samoa on a regular basis which gave way to the American Samoa Longline Limited Entry Permit Program. Since the closing of one of the two canneries in American Samoa in September 2009 landings have declined with vessels transshipping in other regional ports. Despite all the changes in 2009, the U.S. SPTT and the American Samoa longline fleet port sampling program still remains as the main source of data and sampling for the region.