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Yellowfin Tuna |
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Family: Scombridae (Mackerel and Tunas) |
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| Description: The body of the yellowfin tuna tapers at both ends
(cigar-shaped), and the head is conical. The color is dark brownish blue
to dark yellow on the back becoming gray or whitish below. Identifying
tunas can be difficult, especially when yellowfin and bigeye tuna are
involved. In most cases, the length of the pectoral fins can distinguish
each species. The yellowfin has pectoral fins which do not extend past the
anal fin; while in bigeye, the pectoral fins extend well past the anal
fin. Tuna which cannot be distinguished by external characteristics can be
positively identified by liver characteristics. The surface of a
yellowfin's liver is smooth while the liver of the bigeye is striated,
containing many with small blood vessels along the trailing edge. Range: Widely distributed in the Pacific Ocean. In the eastern Pacific, yellowfin tuna occur from Chile to Point Buchon, California. They occasionally enter California waters when ocean temperatures are warm. They usually are not taken in waters less than 70° F with best catches occurring in waters above 74° F. Natural History: The diet of the yellowfin tuna includes juvenile fishes, crustaceans, and squid. They are opportunistic feeders taking whatever is most available in the area. Yellowfin tuna do not spawn off the coast of California; however, they do spawn further south in the eastern Pacific. Some spawning takes place during every month of the year, but off Central America it peaks during January and February. Young fish grow very rapidly and by the time they are 1.5 years old they weigh around 7.5 pounds. At 4 years old they weigh approximately 150 pounds. The largest yellowfin tuna taken are 10 or more years old. These larger fish sometimes have an elongated second dorsal fin. Fishing Information: Yellowfin tuna are fished in much the same manner as albacore; jigs are used to locate the schools, and live anchovies are chummed to keep the fish around the boat. Most yellowfin tuna taken in California weigh 30 to 50 pounds, fish over 200 pounds are occasionally landed. The smaller fish are 1 to 2 years old while the larger ones may be over 10 years of age. Other Common Names: Allison tuna, ahi, Pacific yellowfin. Largest Recorded: No length recorded; 239 pounds (California); weight to 450 pounds. Habitat: Pelagic Environment Source: Marine Sportfish Identification, California Department of Fish and Game, 1987 |
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AUSTRALIA |
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| Also known as Allison Tuna and Ahi
(Hawaii) The caudal fin of the yellowfin tuna is distinctly notched in an "M" chape at the centre of its fork. Behind the second dorsal fin and the anal fin, the body profile of the yellowfin tuna is somewhat flat. The ventral surface of the liver is smooth and the right lobe is longer than the central lobe. Yellowfin tuna adults are distinguished by having a moderately long pectoral fin that is one third to one quarter the body fork length. In juveniles there are about 20 broken pale lines crossing the lower sides. In large fish, the second dorsal and anal fins may be exceedingly elongated and bright yellow. Yellowfin tuna less than 75cm fork length (10kg whole weight) may be difficult to distinguish from small bigeye tuna. A beautiful and colourful tuna. Blue to steel black above, silver to silvery gold on the flanks, silvery white below. In fresh fish a band of bright gold or iridescent blue (sometimes both) runs along the upper flank, separating the dark back from the lighter belly area. The stomach area sometimes carries oval, colourless patches and vague broken vertical bars of white. These are more obvious in juveniles. The yellowfins fins are bright yellow. The finlets, in particular are canary yellow with black margins. In Australian waters fish of between 2 and 80kg are common with some specimens reaching 100kg. In other countries Yellowfin have been recorded in excess of 150kg. Yellowfin is a very good eating fish. It is extremely good as sashimi (raw fish). Yellowfin Tuna are found close inshore, in clean warm currents, but are more common on the Continental Shelf areas. They prefer clean water with water temperatures of 17-27ºC. They rarely venture into dirty, discoloured areas. Yellowfin feed both on the surface, and well down in the water column. Small yellowfin (2-12kg) will take trolled and cast lures, small live baits and sometimes freely drifted pilchards or cut flesh strips. Larger yellowfin take small and medium live baits, up to and including live frigate mackerel, bonito and striped tuna weighing as much as 5kg plus. A favoured Australian technique for taking large yellowfin involves the use of unweighted flesh strip baits or pilchards used in conjunction with a berley trail of fish 'cubes' Yellowfin are extremely powerful and demand the best in tackle and gaffs!
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EQUADOR |
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| Yellowfin Tuna - Thunnus albacares Family: SCOMBRIDAE Vernacular names: Es: Rabil, Fr: Albacore, En: Yellowfin tuna Local names: Colombia: Albacora, Atún
tropical de aleta amarilla, Costa Rica: Atún de aleta amarilla, Chile:
Atún de aleta amarilla, Ecuador: Albacora, Atún de aleta amarilla,
Yellowfin, Tuna, Mexico: Atún de aleta amarilla, Nicaragua: Atún de aleta
amarilla, Panama: Atún de aleta amarilla, Peru: Atún, Atún de aleta
amarilla, Tuno, Tuno de aleta amarilla Geographical distribution: Its distribution
goes from 32° 43' N to 37° 00' S in the Eastern Pacific Ocean. |
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