Background Information
- Stock Condition
Albacore tuna (Thunnus alalunga) is a single species, but fisheries scientists treat the North Pacific and South Pacific populations as two separate management “stocks” because distinct oceanographic barriers, migration patterns, and minimal mixing create functionally self-contained units. By incorporating each stock’s unique biology into their assessments, such as growth rates, spawning seasons, and movement corridors, managers can build more accurate population models and design tailored harvest strategies that keep both stocks sustainable.
Responsibility for managing albacore in the Pacific Ocean is shared across regional fisheries management organizations (RFMOs). The Inter-American Tropical Tuna Commission (IATTC) manages the eastern Pacific portion of the South Pacific albacore stock, while the WCPFC manages the western Pacific portion, underscoring the need for cooperative, Pacific-wide approaches to sustainable albacore fisheries governance. In further recognition of the importance of joint management, the IATTC and WCPFC are working toward establishment of a Joint Working Group that will ensure coordinated management of this important tuna fishery.
The Pacific Community (SPC), as the WCPFC's Scientific Services Provider (SSP), conducts the south Pacific-wide stock assessment on South Pacific albacore across the IATTC and WCPFC Convention Areas. The last stock assessment on South Pacific albacore was conducted in 2024.
Current fishery status
The South Pacific albacore fishery is currently undergoing a major transition in its management framework, moving from limits on the number of fishing vessels to a more dynamic, science-based approach. While the stock itself is not overfished and overfishing is not occurring, fishery participants, particularly some domestic fleets in Pacific Island nations, have raised concerns about declining catch rates and economic viability. Work is underway to finalize a harvest strategy or management procedure that would enable responsive adjustments to fishing pressure. Vessel numbers in the southern Convention Area are capped at early-2000s levels under the existing conservation and management measure, but catch limits have not yet been established.
In a significant policy milestone, Members of the Pacific Islands Forum Fisheries Agency (FFA) agreed in July 2025 to allocations that will form the basis of a binding agreement under the FFA Allocation Framework for South Pacific albacore among southern hemisphere EEZs, laying the groundwork for more equitable and enforceable zone-based management. However, IUU fishing remains a persistent threat to the integrity of the fishery, with several thousand tonnes of albacore estimated to be taken illegally in recent years. The next few months are critical, as the Commission is expected to consider adoption of a Management Procedure and begin discussions on applying controls to high seas areas. Overall, the fishery is stable biologically but still maturing institutionally, with key decisions ahead that will shape its sustainability and economic future.
Importance of the fishery
The South Pacific albacore fishery is a key component of economic security for many Pacific Island countries and territories. It supports domestic longline fleets that provide employment, government revenue, and foreign exchange through licensing and exports, particularly for canning-grade tuna sold to global markets. The fishery also underpins local processing industries and contributes to national development goals in the Pacific Islands.
Science
- Stock assessment
Recent scientific assessments show that the South Pacific albacore population has remained fairly stable since the mid-1970s, after a sharp initial decline. Although there is some uncertainty in the most recent data, especially from 2019 to 2022, the latest analysis suggests the overall condition of the stock has slightly improved compared to the previous assessment. Adult fish are being caught at higher rates, particularly in the eastern Pacific, while younger fish are still being fished at relatively low levels. Encouragingly, there are signs of increasing numbers of young fish entering the population since the late 1990s.
Overall, the albacore stock appears to be in good shape. The current population size is well above the level needed for sustainable fishing, and fishing pressure remains well below critical limits. In fact, the stock is very close to the interim target set by regional fisheries managers. These findings confirm that the South Pacific albacore is neither overfished nor being overfished at this time, and the situation remains broadly in line with the 2021 assessment.
- Stock status and advice
South Pacific albacore tuna plays a vital role in the economies and food systems of many Pacific Island countries. To keep this fishery healthy and sustainable, the WCPFC has set an interim target to maintain the stock at 50% of its unfished level. Based on the latest scientific assessment presented in 2024, the stock is currently close to that target, which means the fishery remains in a good state.
In light of this, the WCPFC Scientific Committee has reaffirmed support for the current target level and emphasized that fishing pressure should not increase. This is especially important in areas where fishing has already grown, like the eastern Pacific. Scientists also strongly encourage the WCPFC to develop and adopt a harvest strategy, including clear rules for managing the fishery into the future. This would allow the Commission to respond more quickly and effectively to changes in the albacore population. The advice also notes the importance of ensuring fair and equitable access to the fishery, particularly for Pacific Island countries and territories, building on recent regional agreements that support more balanced and sustainable fishing.
How does the WCPFC manage South Pacific albacore?
- Current management framework
The inaugural south Pacific albacore conservation and management measure (CMM) was adopted at the 2nd Regular Session of the Commission (CMM 2005-02) and included among the first set of substantive conservation and management measures adopted by the Commission. This was replaced by CMM 2010-05 in 2010 and again in 2015 with what is now the current iteration in CMM 2015-02.
The cornerstone of CMM 2015-02 is the freeze on the number of fishing vessels fishing for South Pacific albacore south of 20°S. Each CCM must keep their number of flagged vessels that actively fished for albacore in that zone at or below its 2005 (or 2000‑2004 average) level. Small Island Developing States (SIDS) may still expand their domestic fleets, but all others remain capped. Every year, CCMs to which the measure applies must report on the number of their vessels that fished for South Pacific albacore, and their catch, which includes other species such as bigeye tuna, yellowfin tuna, swordfish, other billfish, and sharks. Additionally, CCMs are encouraged to collaborate on research that reduces uncertainty about the status of the stock, supporting long-term sustainability and economic viability.
Current reporting requirements for South Pacific albacore have changed over time, aimed at ensuring the Commission received information to clarify baselines and to support monitoring of compliance with the quantitative limits.
Historical data from 2006 to 2014 was initially required by each CCM participating in the fishery, with annual updates thereafter, and earlier data is encouraged when available. These reporting requirements allow the WCPFC to monitor fishing effort and stock status over time.
The measure is reviewed annually based on the Scientific Committee’s advice, ensuring it remains adaptive to changes in fishery dynamics and emerging scientific evidence.
- Management issues
Because the cap only limits the number of vessels, fleets have been able to fish harder with the same (or even fewer) hulls. In 2024, longline vessels set an estimated 216 million hooks, a 6.9% jump on 2023, even though vessel numbers did not rise. They landed 89,632t of albacore (97% of all gears, +7 % year‑on‑year), while the small troll fishery brought in 1,485t (+25%). About 23% of longline fishing days now occur on the high seas, with two "hotspots", one east of French Polynesia and the other just east of New Zealand, showing the highest catch‑per‑unit‑effort (CPUE).
Major fleets recorded very different catch‑rate shifts in 2024: Japan +64%, Fiji +25%, Chinese Taipei +23%, China –16%. High‑seas transhipments remain seasonally heavy (peaking around September) and, while 2024 totals are still preliminary, they continue the upward post‑2016 trend.
A review of the 2024 stock assessment at the 20th Scientific Committee (SC20) revealed that South Pacific albacore is still in good shape: the breeding population sits at roughly 48% of its natural, unfished size, comfortably above the “red‑line” of 20% and only a little below the Commission’s current goal of 50%. In other words, the stock is neither overfished nor being overfished right now.
SC20 did, however, flag two warning lights:
- Effort creep – Even though the number of longline vessels is frozen, fleets are setting more hooks and using better technology, so the actual fishing pressure on adult fish is inching upward.
- Geographic shift – More longline catch is coming from the eastern Pacific and from a few “hotspots” on the high seas, raising the risk that local pockets of albacore could be thinned out even while the overall stock looks healthy.
Because of these trends, SC20 asked the Commission to review its interim biomass target (testing a wider band of 42 – 56% of the unfished level) and to experiment with harvest control rules that would limit total catch or effort, not just the number of vessels, to keep future fishing pressure in line with stock health.
- Improving future management
CMM 2015‑02 still succeeds at holding down fleet size, and the stock remains biologically healthy; however, the latest indicators show that total hooks, total catch, and high‑seas concentration are all rising inside the vessel cap. SC20’s call to look beyond static boat numbers and toward dynamic limits on hooks, catch or high‑risk areas, reflects this reality. In other words, the measure continues to provide a stable foundation, but the fishery’s evolving footprint and fishing power suggest that future management will need to track effort and spatial patterns more closely, not just count boats, if it is to keep South Pacific albacore on its current sustainable path.