What Divers Should Know About Yellowfin Tuna

Gliding through the open blue, one might suddenly encounter the striking form of a Yellowfin tuna, easily identified by its namesake bright yellow second dorsal fin, anal fin, and finlets. Its main body presents a sleek, very dark metallic blue, fading to silver on the belly, which often displays about 20 vertical lines. These magnificent fish primarily inhabit the pelagic waters of tropical and subtropical oceans worldwide.

Yellowfin tuna are among the larger tuna species, reaching weights over 180 kg (400 lb) and lengths up to 2.4 meters (7 ft 10 in). Primarily epipelagic, they mostly range within the top 100 meters (330 ft) of the water column, making them accessible in many recreational diving areas. While typically found in deep offshore waters, they can approach mid-ocean islands or even continental shelves when conditions are suitable and baitfish are abundant, offering unique encounters.