Tuna, Vietnam Yellowfin
Yellowfin tuna is a species of tuna found in waters of tropical and subtropical oceans worldwide.
The yellowfin tuna is one of the largest tuna species, reaching weights of over 300 pounds but is significantly smaller than the Atlantic and Pacific bluefin tunas that can reach over 1,000 pounds and slightly smaller than the bigeye tuna and the southern bluefin tuna.
The second dorsal fin as well as the finlets between those fins and the tail, are bright yellow, giving this fish its common name.
Although mainly found in deep offshore waters, yellowfin tuna may approach shore when suitable conditions exist. Mid-ocean islands in the Western Pacific, Caribbean and Maldives islands Indian Ocean, as well as the volcanic islands of the Atlantic such as Ascension Island often harbor yellowfin feeding on the baitfish these spots concentrate close to the shoreline. Yellowfin may venture well inshore of the continental shelf when water temperature and clarity are suitable and food is abundant.
Yellowfin tuna often travel in schools with similarly sized companions. They sometimes school with other tuna species and mixed schools of small yellowfin and skipjack tuna, in particular, are commonplace. They are often associated with various species of dolphins or porpoises, as well as with larger marine creatures such as whales and whale sharks.
Yellowfin tuna prey include other fish, pelagic crustaceans, and squid. Like all tunas their body shape is evolved for speed, enabling them to pursue and capture fast-moving baitfish such as flying fish, saury and mackerel.
Yellowfin tuna is widely used in raw fish dishes, especially sashimi. This fish is also excellent for grilling. Yellowfin is often served seared rare.
Yellowfin buyers recognize two grades, "sashimi grade" and "other", although there are variations in the quality of "other" grades.
Yellowfin is becoming a popular replacement for the severely depleted supplies of southern bluefin tuna.