They swim alone or in very loose aggregations. They are frequently found basking at the surface, airing their first dorsal fin. Boaters report this to be a beautiful sight, as is the powerful jumping for which the species is known.
Found in warm temperate waters of the Atlantic, Pacific and Indian Oceans, this schooling, pelagic, seasonally migratory species is suspected of making rather extensive migrations. Schools bigeye tuna generally run deep during the day.
Known as ahi in Hawaii, yellowfin fillets and steaks have developed quite a following across the U.S. Tuna is graded for sale, with sashimi as the number one grade indicating a good color and high fat content. In good tuna, the bloodline should glow like fresh blood. Tuna should be chilled on ice quickly. Yellowfin is more perishable than bigeye or albacore and requires extra care when handling.