- Although the flesh of the almaco jack is considered quality table fare, the species has been associated with ciguatera poisoning, a seldom fatal stomach irritation.
- The almaco jack is susceptible to tapeworm parasites in the caudal peduncle area, but the meat can be eaten safely if affected portions are cut away.
Yellowfin tuna (Thunnus)
Yellowfin tuna have a muscular, streamlined body and, like all tuna, are extremely fast swimmers. Coloration is dark metallic blue to black on the back and tail fin, yellow and silver on the side and belly. The second dorsal and anal fins are yellow and very long in older fish. Finlets run down the back and belly from these two fins to the tail fin and are a bright, canary yellow with black edges. The belly often has as many as 20 vertical, broken lines that are more pronounced in young yellowfin tuna than in adults.
The yellowfin’s diet varies depending upon forage available in a given area. Various baitfish, crustaceans and squids make up the bulk of their diet. The feed most often at or near the surface and are often active at night.
Yellowfin tuna are found worldwide in tropical and some subtropical waters. These bodies of water include all three warm oceans (Pacific, Atlantic, Indian) and all warm seas except the Mediterranean.
Though they can withstand cooler water, yellowfin tuna prefer warm water and are found mainly in waters between 62 and 80 F. Yellowfin tuna, particularly young fish, usually school below the surface but over deep water, often several hundred feet. They avoid depths because of their intolerance for low concentrations of oxygen.
Adults often form schools with other tuna species, mainly bigeye and skipjack tuna. They school primarily by size and larger fish will also school with porpoises. Though yellowfin tuna are sometime found near shore, this only occurs when forage suddenly becomes abundant there, and for the most part they can stay around the edges of continental shelves.
� The Hawaiian name for yellowfin tuna, “ahi,” is the Hawaiian word for “fire.”
� At one point, extremely large yellowfin tuna with very long second dorsal and anal fins were thought to be a separate species.
� The IGFA record is 388 pounds, 12 ounces landed off of Mexico in 1977.