English: Yellowfin Tuna 
Latin: Thunnus albacares
Size + Weight:  Today about 40-180 cm abt 5-20 kg
Biggest Angled Fish:  175 kgs, Mexico 1977 by Curt Wiesenhutter
Catching Areas:  25% Eastern Pacific, 35% Western Pacific, 25 % Indian Ocean , 15% Atlantic Ocean
Catching Methods:  Mostly purse seining, also long-line 
Share of all Tuna Caught:  About 35% or 1.100.000 m/t
Main Production Areas: Thailand, Philippines, Indonesia, Mexico, Venezuela, Ecuador, Colombia, Spain, Italy
Life Cycle:  About 4-7 years 
Major Markets:  Japan, Western-Europe, United States
Popular Product Forms:  Canned, Fresh (whole fish), Frozen Loins , Fresh Fillets, Smoked
More Detailed Description:  Easily to recognize by the sickle-shap of their anal and second dorsal fins.Yellowfin is the second tuna species is terms of volume and popularity. They are found between 45oN and 40oS. They cover enormous distances around the globe, and all stocks mingle. It is a big fish, which can swim at very high speed, which may be one of the reasons why in some areas, dolphins and large full-grown yellowfin swim together. Through extensive measures from the side of the tuna industry, and the creation of some very good monitoring programs. Fortunately the volume by-catch of dolphins has become insignificant now in relation to the its natural mortality, and was below 500 dolphins on a global basis.
Product Characteristics: In cooked form the yellowfin meat tends to have a to very light yellow/brown color. The structure of the meat is quite firm, and the taste is mild. If the fish gets larger then 10-15 kgs the meat tends to become slightly darker and somewhat dryer. The large size of the yellowfin make it well fit for solid pack in cans.
Future Supply: Scientific analyses suggest that yellowfin is exploited to its optimum in the Eastern Pacific ocean, and also in the Western Pacific there will not be any significant growth in volume for the future. In the Indian Ocean exploitation leaves little space for increase. The general concerns on yellowfin is that due to increased catches of baby-yellowfin (especially in the Atlantic, Indian Ocean and Western Pacific), the stocks might suffer on the long term.

Habitat :
The Yellowfin tuna is an epipelagic, oceanic fish, able to live above and below the thermocline, at temperatures of 18 to 31°C.  Most of them can generally be found in the upper 100 m of the water column.
Distinctive Features:
The Yellowfin is the second largest tuna species. Its body is strongly fusiform shaped, and is deepest under its first dorsal fin and tapering considerably towards the caudal peduncle. There are two dorsal fins present. In mature fishes the second dorsal fin and the anal fin (directly below the second dorsal) are very long, and they will become relatively longer in larger individuals. The pectoral fin is also quite long compared to other species, reaching beyond the space between the dorsal fins. The caudal peduncle is very slender and consists of three sets of keels. There are seven to ten dorsal and ventral finlets present. A band of large scales form a circle around the body behind the head, and scales are lacking behind the corselet. The Yellowfin tuna have small eyes and conical teeth. A swim bladder is present in this tuna species.

Their bodies have a metallic dark blue or greenish color in the upper part, while the belly and lower sides are silvery white and they are crossed by many vertical interrupted lines. Perhaps the most distinctive is a golden stripe that runs along the sides. The second dorsal, anal fins and finlets have bright yellow color, and the finlets are bordered by a narrow band of black.
Size, Age, and Growth :
The maximum length reported for Yellowfin tuna is 280 cm total length and the maximum weight is 400 kg. The all-tackle record recognized by the International Game Fish Association (IGFA) is 176.4 kg. The latter also indicates the more common maximum size for this species.
The size of Yellowfin tuna at maturity varies by region, and could also vary between individuals found near- and offshore. Yellowfin reach the status of mature by the time they reach a length of 120 cm in fork length at an age of about 2 to 3 years; however there are some exceptions where fish become mature at the size of 50 to 60 cm in fork length at an age of about 12 to 15 months. The sex ratio is approximately 1:1 in juvenile fishes and adults up to 140 cm.
The reproduction of Yellowfin tuna occurs all year-round, but is most frequent during the summer months in each hemisphere. In the tropical waters of Mexico and Central America, it has been determined that Yellowfin spawn at least twice a year. It is believed that 26°C is the minimum temperature for spawning and each female spawns several million eggs per year.
Among the tuna species, the larval of Yellowfin tuna can be identified by a lack of pigment on the tail and by the presence of a single spot of black pigment under the chin.
The Yellowfin juveniles grow quickly, weighing approximately 3.4 kg at 18 months and 63.5 kg at 4 years.

Stock Status of Yellowfin Tuna:
Regional Management Organization
State of Stock
Last Edited
Atlantic Ocean
Fully exploited
Year 2008
Indian Ocean
Year 2007
Eastern Pacific Ocean
Fully exploited
Year 2008
Western and Central Pacific Ocean
Fully exploited
Year 2008

The Yellowfin tuna is currently listed of having a low risk and least concern in the redlist of World Conservation Union (IUCN).


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