PRINCIPAL MARKET TUNAS

Historical evolution
The global production of the principal market tunas increased relatively steadily from less than 0.2 million tonnes in the early 1950s to a peak of 4.3 million tonnes in 2003, declining slightly in 2004 (Figure 1). In the early 1950s, most catch (about 80 percent) was taken in the Pacific. Between 1970 and 1978, catches increased significantly as a result of the expansion of fisheries in the eastern Atlantic and the development of new offshore fishing grounds in the eastern Pacific. Between 1978 and 1984, many vessels moved to the western Pacific and the western Indian Ocean, developing new fisheries there. In the mid-1980s, catches of the principal tunas increased to 2.4 million tonnes. By 1994, they had increased to 3.4 million tonnes with better oceanographic conditions after the transfer of vessels. The development of FAD fishing also contributed to these increases.

By species
Skipjack, which is used mostly for canning, accounts for the greatest proportion of the world catches of tuna (Figure 1). Catches tended to increase over the entire period of its exploitation. In 2003, the skipjack catch was about 2.2 million tonnes (the highest on record), representing about half of all the principal market tuna landed. In the early 1980s, catches of skipjack increased steadily as a result of expansion of fishing effort into the tropical western and central Pacific (Figure 3) and the western Indian Ocean (Figure 4). These increases continued in the following years. The development of purse seine fisheries on FADs in the 1990s contributed to further increases in catches of tropical tuna species including skipjack. In the Atlantic, catches of skipjack peaked at 0.24 million tonnes in 1991, decreasing to 0.19 million tonnes in 2004 (Figure 5) and thus contributing relatively little to the global catches of the species.

Yellowfin is commercially the second most important species of tuna by weight. Most yellowfin is used for canning, but more and more of the catches are being sold in fresh fish markets (and also as frozen fish). Similarly as with skipjack, for the same reasons, catches of yellowfin have tended to increase up to now, reaching 1.3 million tonnes in 2004 (Figure 1). Catches in the Atlantic peaked at 0.19 million tonnes in 1990 and then tended to decrease to 0.12 million tonnes in 2004 (Figure 5). Catches from the Indian Ocean increased to 0.49 million tonnes in 2004 (Figure 4). Catches of yellowfin from the Pacific reached a peak at 0.86 million tonnes in 2002, decreasing to 0.70 million tonnes in 2004 (Figure 3).

Bigeye, the third most important species in terms of landed weight (Figure 2) is similar in appearance to yellowfin. However, unlike yellowfin, bigeye tunas are primarily creatures of the deep, spending most of their lives in cold waters below the upper mixed layer of the ocean where they used to be traditionally captured mainly by longline gear. Their high fat content (for insulation from the cold water) makes them desirable for the Japanese sashimi market. The rapid and substantial increase in catches in the mid-1970s resulted from modifications of longline gear which enabled it to be used in much deeper water than previously. However, more recently the longline catches of large bigeye tunas have been declining, while purse seine catches of smaller bigeye, particularly in association with FADs, increased rapidly in the 1990s, resulting in continuous large increases of total catches for the species to a maximum of 493 000 tonnes in 2000, declining slightly from that level in subsequent years. The increases of bigeye purse seine catches around FADs resulted in complications for fisheries management and allocations among participants in the fisheries harvesting bigeye.

World production of albacore, used mostly for canning, increased from 1950 to the late 1960s. It has fluctuated without a clear trend since then with catches of 220 000 tonnes in 2004 (Figure 2). During the 1980s and early 1990s, driftnet fisheries made large catches of small albacore on the high seas in the southwestern and northeastern Pacific. Even with the termination of these fisheries, the total albacore catch in the Pacific significantly increased from the level before 2001, peaking at 172 000 tonnes in 2002 (Figure 3).

Atlantic, Pacific and southern bluefin contribute relatively little in terms of volume to the total catches of principal market tunas (Figure 2), but their individual value is high because of their use for sashimi. The catch of these species peaked at about 150 000 tonnes in 1961, following a steep decline in the late 1960s as a result of decreased catches of southern bluefin.

Catches of Atlantic bluefin tended to decline from the early 1950s to the early 1970s. During the next decade and a half, catches fluctuated without trend. In the early 1990s, reported catches increased rapidly to 53 000 tonnes in 1996 probably as a result of improved reporting in the Mediterranean Sea. Catches declined after 1996 and have stabilized at about 35 000 tonnes in the last period. The catch reported in 2004 (34 500 tonnes) was slightly over the total allowable catch (TAC) of 32 000 tonnes, but scientists at the International Commission for the Conservation of Atlantic Tunas (ICCAT) estimated it to be about 50 000 tonnes.

The catch of Pacific bluefin peaked at 32 000 tonnes in 1966 and 1981. The smallest catch was 8 000 tonnes in the early 1990s. Catches have fluctuated upwards since then, in the order of 29 000 tonnes in 2000, but decreasing to 22 000 tonnes in 2004.

Catches of southern bluefin increased steeply from 800 tonnes in 1952 to 81 000 tonnes in 1961. They fluctuated without a trend between 41 000 tonnes and 66 000 tonnes until 1974. Catches of the species decreased steeply and steadily from 45 000 tonnes in 1980 to 13 700 tonnes in 1991. The reported catches have remained between 13 000 tonnes and 20 000 tonnes since then, with 13 500 tonnes reported in 2004. Recently, a possibility of substantial under-reporting of southern bluefin catches over the last ten to 20 years was identified.

Catches from individual stocks of the principal market tunas are shown and discussed in the context of the status of these stocks (see the Tuna and tuna-like species - Global factsheet).

Figure 3 Catches of principal market tunas in the Pacific (‘000 tonnes)

Figure 4 Catches of principal market tunas in the Indian Ocean ('000 tonnes)

Figure 5 Catches of principal market tunas in the Atlantic ('000 tonnes)

By ocean
Historically, the largest proportion of principal market tunas has always been taken from the Pacific Ocean (Figure 6). Between 1998 and 2002, the annual catch of these species in the ocean remained quite stable at about 2.5 million tonnes. This represents approximately 65 percent of global annual catch of the principal market tunas. Skipjack and yellowfin contribute about 86 percent of the total catch in the Pacific.

Until the mid-1980s, catches of the principal market species in the Atlantic and the Mediterranean Sea were greater than those in the Indian Ocean but around the mid-1980s, the Atlantic catches became smaller than those in the Indian Ocean. The transfer of some vessels from the Atlantic to the Indian Ocean contributed to this change. Catches in the Atlantic continued to increase until 1994 when the maximum annual catch of 0.63 million tonnes was taken, representing almost 18 percent of global landings of the principal market tunas. In 2004, Atlantic landings were 428 000 tonnes. Bigeye, skipjack and yellowfin contribute about 70 percent of the total catches of principal market species there.

Prior to the 1980s, the catch from the Indian Ocean accounted for less than about 8 percent of world production of the principal market tunas. As a result of the expansion of tuna fishing operations in the ocean, catches of skipjack and yellowfin increased rapidly in the 1980s. Consequently, catches of the principal market tunas in the Indian Ocean surpassed those in the Atlantic Ocean, accounting for about 26 percent of global landings of the principal market tunas in 2004 (i.e. around 1.1 million tonnes). At present, skipjack and yellowfin contribute about 86 percent of the total catches of the principal market tunas from the Indian Ocean.

Figure 6 Catches of principal market tunas by ocean (‘000 tonnes)

By country/entity
The principal market tuna catches of Japan and Taiwan Province of China are now the largest (more than 0.5 and 0.4 million tonnes caught in 2004, respectively) of all countries (Figure 7). Other important tuna fishing countries include Indonesia (341 948 tonnes), the Philippines (278 000 tonnes), Spain (268 585 tonnes), Republic of Korea (231 320 tonnes), Papua New Guinea (206 678 tonnes), France (165 767 tonnes), Ecuador (157 293 tonnes), Mexico (141 871 tonnes), Maldives (135 919 tonnes), Islamic Republic of Iran (105 247 tonnes), United States of America (99 917 tonnes), Seychelles (87 990 tonnes), Bolivarian Republic of Venezuela (81 432 tonnes), Sri Lanka (73 910 tonnes), Colombia (69 068 tonnes), China (64 410 tonnes), Vanuatu (63 439 tonnes), Panama (59 291 tonnes) and Ghana (55 681 tonnes).

Particularly off Southeast Asia, in both the Indian and Pacific Oceans, tuna fisheries are growing, including the artisanal sector catching mostly small tunas, skipjack and yellowfin. This sector’s growth has also been significant in the entire Indian Ocean. Further information on fishing countries/entities is given in Table 1 - Catches of principal market tunas in 2004 by stock, fishing gear and country (tonnes)

Figure 7 Catches of principal market tunas by ocean (‘000 tonnes)

OTHER TUNA AND TUNA-LIKE SPECIES

The catches of tuna and tuna-like species other than the principal market tunas also significantly increased from about 0.5 million tonnes in the early 1970s to nearly 5.2 million tonnes in 2004, fluctuating significantly since the late 1980s. Historical trends of catches of these species divided into billfishes, bonitos, mackerels, seerfishes and small tunas (tunas other than the principal market tunas) are presented in Figure 8.

Less than 10 percent of these catches are composed of billfishes, taken mainly in the Pacific and Atlantic. In terms of weight (catches in 2004), the most important species of tunas and tuna-like species other than the principal market tunas are chub mackerel (2 017 276 tonnes), Atlantic mackerel (708 710 tonnes), Indian mackerel not specified (498 124 tonnes), Japanese Spanish mackerel (427 990 tonnes), frigate and bullet tunas (295 385 tonnes), Indian mackerel (218 676 tonnes), narrow-barred Spanish mackerel (196 483 tonnes), longtail tuna (143 329 tonnes), kawakawa (133 903 tonnes) and swordfish (109 622 tonnes).

Figure 8 Catches of billfishes, bonitos, mackerels, seerfishes and smll tunas (other than the principal market tunas) (‘000 tonnes)