Yellowfin have a dark blue back with a yellow lateral band on the upper sides. The lower sides and belly are silvery-gray, often with chains of white vertical lines and spots. The 2nd dorsal and anal fins are yellow, and the finlets are yellow with a narrow black margin. A warm-water species, yellowfin is the most tropical species of tuna, and is abundant in tropical waters throughout the Atlantic. Young are known to form large schools near surface.
Adults inhabit fairly deep water but also live near the surface.
Yellowfin are often found mixed with other species, especially skipjack and bigeye. Distinctive Characteristics Albacore can be distinguished from other tunas by a long pectoral fin that may reach to a point beyond the anal fin. The pectoral fin in juvenile albacore may be similar to that of yellowfin or bigeye. A swimbladder is present, but is poorly developed and not evident in individuals smaller than about 25-32 gill rakers on the first gill arch. Albacore lack any stripes or spots on the lower flanks and belly.