Greater amberjacks, Seriola dumerili, are the largest of the jacks. They usually have dark stripes extending from nose to in front of their dorsal fins. They have no scutes and soft dorsal bases less than twice the length of the anal fin bases. They are usually 40 pounds or less, and are found associated with rocky reefs, debris, and wrecks, typically in ten to 40 fathoms.
Lesser amberjacks, Seriola fasciata, have a proportionately larger eye and deeper body than the greater amberjack. They are olive green or brownish-black with silver sides and usually have a dark band extending upward from their eyes. Juveniles have split or wavy bars on their sides. The adults are usually under ten pounds. They are found deeper than other jacks, commonly 30 to 70 fathoms.
Amberjacks feed on squid, fish, and crustaceans, and are thought to spawn offshore throughout most of the year.
Two United States Navy submarines have been named USS Amberjack.
The MC 109 manned offshore oil platform operated by British Petroleum is named "Amberjack." It is 13.3 miles from shore at 28°51'27"N, 88°55'51"W in 1100 feet of water.