Yellowfin Tuna are literally the rockets of the sea. They are among the largest tuna in the sea, and the fact that they can reach sizes as large as 400 lbs, means that they are one of the ultimate tests of your fly fishing ability. Yellowfin range along both coasts of the USA with the Pacific fish found generally south of San Diego. Yellowfin tuna are torpedo-shaped with dark metallic blue backs, yellow sides, and a silver belly. They have very long anal and dorsal fins and finlets that are bright yellow. Yellowfin can live up to six or seven years. They are highly migratory and are found throughout the Pacific, Atlantic and Indian Oceans. They form schools with other tunas like skipjack and bigeye, and are also known to associate with dolphins. Yellowfin is often marketed as ahi, from the Hawaiian ʻahi. Yellowfin tuna probably first came to the attention of sports fishermen when they appeared on the tuna grounds of Catalina Island in southern California. Yellowfin tuna were subsequently discovered by sport fishermen in Bermuda, the Bahamas and Hawaii.