Intrinsic rate of increase is 0.12 (PFMC 2003). Age at maturity is 5 years in the Atlantic and Pacific and 2 years in the Mediterranean (ICCAT 2004; PFMC 2003). Growth rate is estimated to be between 0.10 and 0.18 (IOTC 2004). Maximum age is approximately 12 years in the North Atlantic (Bard 1981) and 15 years in the South Atlantic (Lee and Yeh 1993). In the North Pacific, maximum age is approximately 10 years (PFMC 2003).

There is evidence that yearly changes in climate due to the North Atlantic Oscillation may affect recruitment and migration patterns of juvenile Albacore Tuna (ICCAT 2004). In the Pacific, low numbers of young Albacore Tuna survived their early years of life (i.e., recruitment was low) during El Niño events in the 1980s and 1990s. Recruitment to the Pacific population of Albacore Tuna also seems to track Pacific Decadal Oscillation events (SCTB 2004).

We chose not to subtract points, however, because the data do not indicate high population variability resulting from these environmental changes.

Albacore Tuna are highly fecund, broadcast spawners, and females spawn millions of eggs at a time (NMFS 1999).

Albacore Tuna are a highly migratory species found worldwide in tropical and temperate oceans (ICCAT 2004; PFMC 2003).

In general, there has been a remarkable decline in large predatory fish populations worldwide (Myers and Worm 2003). Most Albacore Tuna populations are not doing poorly relative to fishery managers’ target abundance levels (e.g., BMSY), but their populations are depleted compared to historic levels.

At last assessment in 2000, Albacore Tuna were overfished in the North Atlantic. Managers estimated that the North Atlantic population size was only 68% of the target population size, which they define as the biomass needed to produce maximum sustainable yield (BMSY). Currently, there is considerable uncertainty associated with this biomass estimate, and a new assessment is needed (Zarate, pers. comm., 2005). The South Atlantic population is doing better: a 2003 assessment placed it at 166% of BMSY, with an 80% confidence interval of 74 to 181% of BMSY. The number of spawning adults has declined substantially but also still remains above the target number (ICCAT 2004).

No estimates of current biomass, maximum sustainable yield, or fishing mortality exist for Albacore Tuna in the Mediterranean (ICCAT 2004).

In the North Pacific, managers believe that the population size of Albacore Tuna is 30% of its unexploited size (IATTC 2004). They do not have good abundance estimates, however, and levels of fishing pressure remain the best available proxy for abundance. Fisheries targeting North Pacific Albacore Tuna are currently fishing at a rate that reduces the average egg production per female to 20% of the unfished level (F20%; IATTC 2004). This level of fishing mortality is moderately high, and this population should be monitored carefully (Crone, pers. comm., 2004).

In the Eastern Pacific, Albacore Tuna are still abundant, and managers consider the impact of fisheries on the population to be low. Population size is greater than BMSY, and, in 2000, managers estimated that fishing has reduced population size by only 10% (IATTC 2004; Hampton 2002). Recent catches have not exceeded 40,000 metric tons (mt), which is much lower than the sustainable yield of 117,000 mt (IATTC 2004).

Similarly, in the Southwestern Pacific, Albacore Tuna remain relatively abundant. In 2003, managers estimated that biomass the previous year was 130% of BMSY (WPFMC 2003).

To account for the range in abundance across all regions, a medium score was awarded for Albacore Tuna.

In the North Atlantic, there has been an overall downward trend in Albacore Tuna abundance since the mid-1980s. In the South Atlantic, the number of mature adults has declined since the 1980s but remains above the number of spawners needed to produce maximum sustainable yield (ICCAT 2004). There are no biomass estimates available for Albacore Tuna in the Mediterranean; and catch data show no major trend over time, except that catches peaked in 2003 at 7,415 metric tons (mt; ICCAT 2004).

Biomass of Albacore Tuna in the North Pacific is estimated to be 510,000 mt, which is 40% higher than the 1975 biomass level. Recruitment to the population was greater in the 1990s than in the 1980s, and catch per unit effort (CPUE) for many North Pacific Albacore Tuna fisheries has increased (IATTC 2004).

Biomass in the South Pacific, however, is estimated to be 60% of the 1950s biomass level (SCTB 2004). In American Samoan longline fisheries, CPUE decreased by 36% in 2003 from the 2002 level (Ito and Hamm 2004).

CPUE data in the Indian Ocean show a sharp decline: in 1960-64, CPUE was high (10 fish/1000 hooks), but it has since declined to less than 2 fish/1000 hooks. However, managers speculate that this decline may indicate changes in targeting strategy of fishers, not changes in abundance and suggest caution when using CPUE data as a measure of Indian Ocean Albacore Tuna abundance (IOTC 2004).

Points were subtracted here to account for the greater number of declining Albacore Tuna populations than increasing populations.

The North Atlantic population of Albacore Tuna is listed as overfished, but the South Atlantic population is not (ICCAT 2004). Fishing mortality of Albacore Tuna is high in the North Pacific; however, the population is not overfished (Crone, pers. comm., 2004). Neither the South Pacific or Indian Ocean population of Albacore Tuna is listed as overfished (IOTC 2004; SCTB 2004).

To account for the range in status of all Albacore Tuna populations, we chose not to subtract points.

Pole and troll gears fish near the ocean surface and are likely to have a low impact on habitat.

In the North Atlantic, surface and longline fisheries target Albacore Tuna. The surface fleets (mainly baitboats, Spanish trollers, and French and Irish mid-water paired pelagic trawl vessels) target juveniles and sub-adults, while Taiwanese longline fleets target sub-adults and adults. In the South Atlantic, Albacore Tuna are mainly caught with South African and Namibian baitboats that mainly catch juveniles and Brazilian and Taiwanese longline fleets. The longline fleets either target Albacore Tuna or catch them incidental to Swordfish and Bigeye Tuna (ICCAT 2004).

In the Eastern Pacific, troll fisheries catch the largest proportion of Albacore Tuna, whereas in the North Pacific, longline and pole-and-line gear dominate the Albacore Tuna fishery, followed by troll gear (IATTC 2004).

In the Western and Central Pacific, longline and pole-and-line gears dominate the Albacore Tuna fishery. In the South Pacific, the majority of catches are made with longline gear, followed by troll gear (SCTB 2004).

In the Indian Ocean, pole and troll gears catch less than 2% of the annual Albacore Tuna catch (IOTC 2004).

Oceanic habitat is likely healthy enough to support robust populations of Albacore Tuna.

Effects of pole and troll gears are likely minimal.

Effects of pole and troll gears are likely minimal.

Many international agencies are involved in the research and management of tuna species and the fisheries that target them. Overall, they have only succeeded in stabilizing tuna biomass at low levels compared to historic levels (Myers and Worm 2003).

Several of these agencies have mandates to recommend management measures to member countries. They are the International Commission for the Conservation of Atlantic Tunas (ICCAT), the Inter-American Tropical Tuna Commission (IATTC) in the eastern Pacific, the Commission for the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean, and the Indian Ocean Tuna Commission (IOTC). Other organizations conduct research and population assessments and include the North Pacific Albacore Workshop, the Forum Fisheries Agency in the South Pacific, and the Standing Committee on Tuna and Billfish (SCTB).

Despite the abundance of tuna commissions, overall, there is very minimal management in place for Albacore Tuna. Quotas are in place in the Atlantic only, yet, in the North Atlantic, the Albacore Tuna population is overfished. In the South Atlantic, the Total Allowable Catch (TAC) was exceeded twice in the last 4 years. There are no ICCAT regulations managing Albacore Tuna fisheries in the Mediterranean, despite the rapid increase in landings over the last 10 years (ICCAT 2004).

Current catch levels in the Indian Ocean are not sustainable, and estimates of abundance based on catch-per-unit-effort data are unreliable. Managers do not understand the structure of the Albacore Tuna population, or even if there is significant mixing between the South Atlantic and Indian Ocean populations (IOTC 2004).

There has not been an assessment of the North Atlantic population of Albacore Tuna since 2000. Also, the status of Albacore Tuna in the Mediterranean Sea has yet to be assessed, despite recent, record-high catch levels. Uncertainty in catch-at-size data for the North and South Atlantic populations prevented managers from having confidence in the 2000 and 2003 population assessments (ICCAT 2004).

In the Indian Ocean, data on catch effort and size frequencies in several longline fisheries are unavailable (IOTC 2004).

Also, non-reported longline catches from the Atlantic, Pacific, and Indian Oceans have been increasing since the 1990s (Crowder and Myers 2001).

At last assessment in 2000, managers found that North Atlantic population of Albacore Tuna was overfished. They recommended a total allowable catch limit (TAC) of 34,500 metric tons (mt) to protect the breeding population (i.e. the spawning stock biomass). More recently, they have determined that a catch limit of 31,000 mt is necessary to rebuild the number of spawning adults to the level that will support maximum sustainable yield. 2003 catch levels were below the TAC, but it remains unclear if this catch limit is low enough to enable the population to rebuild (ICCAT 2004).

Because only one population of Albacore Tuna is listed as overfished, we chose not to subtract points here.

In the North Atlantic, where Albacore Tuna are overfished, the number of vessels in the fishery is limited to the average number of vessels that were present in the fishery from 1993 to 1995 (ICCAT 2004).

We chose not to add here, because capacity of Albacore Tuna fisheries is only controlled in one region.

Although we were not able to find quantitative estimates of bycatch for the world's pole and troll Albacore Tuna fisheries, data collected by U.S. fishery managers on domestic and international fisheries is useful. In the Atlantic, small numbers of Bluefin, Yellowfin, and Bigeye Tuna are discarded in commercial handgear fisheries that land Albacore Tuna in the Atlantic (NMFS 2003).

U.S. observer data show that Albacore Tuna pole and troll fisheries discard only minor amounts of undersized Albacore, Skipjack, Bluefin, and Yellowfin Tunas, Dorado, billfishes, and sharks. According to the Pacific Fishery Management Council, bycatch in foreign Albacore Tuna pole and troll fisheries is essentially the same as in U.S. fisheries. (PFMC 2003).

The Western Pacific Fishery Management Council also reports pole and troll fisheries are very selective for desired species and sizes. For example, catches in the Hawaiian pole-and-line fishery for Skipjack Tuna are comprised of 99.6% Skipjack Tuna (WPMFC 2002).

In the Eastern Pacific Ocean, purse-seine fisheries that target Yellowfin, Skipjack, and Bigeye Tunas also capture Albacore Tuna. Californian and Hawaiian longline fisheries discard 9.3% of the Albacore Tuna they catch (Ito and Hamm 2004). We chose not to subtract here, however, because mortality due to bycatch does not seem to be a major problem for Albacore Tuna populations.

Pole and troll fisheries have few discards and very low bycatch of threatened, endangered, and protected species. They are a model for selective fisheries.

Pole and troll fisheries have very low bycatch of non-targeted species and are a model for selective fisheries. Discarded fish, including undersized individuals, are usually in a viable condition (WPFMC 2002).

Pole and troll fisheries are a model for selective fisheries.