Bigeye Trevally, Caranx sexfasciatus
The Bigeye Trevally, Caranx sexfasciatus, whose common Spanish name is jurel voraz, is a member of the Jack or Carangidae Family, known collectively as jureles and pámpanos in Mexico. Globally, there are seventeen species in the genus Caranx, nine of which are found in Mexican waters, three in the Atlantic and five in the Pacific and one in both oceans.
The Bigeye Trevallies have moderately compressed deep elongated bodies with a depth that is 24 to 28% of standard length. They are iridescent blue-brown dorsally and transition to silvery-white ventrally. They have a small black spot near the upper end of their gill covers and their dorsal fin lobe has a white tip. Their scutes are yellowish-black. They have a rounded head profile with disproportionately large eyes, after which they are named. They have 15 to 19 gill rakers and 27 to 36 strong scutes. Their lateral line has a pronounced and relatively long anterior arch. Their anal and dorsal fins have long lobes and their pectoral fins are longer than the head. Their caudal fin is widely forked. Their body is covered with small scales.
The Bigeye Trevallies are a nocturnal pelagic schooling species found at depths up to 315 feet that aggregate adjacent to reefs during the day. They reach a maximum length of 1.2 meters (3 feet 11 inches) and 14.3 kg (31.5 pounds) in weight. Juveniles are known to frequent estuaries and fresh water environments. They are opportunistic predators feeding on benthic and pelagic fish as well as squid and crustaceans. They are a favorite prey of sea lions.
In Mexican waters the Bigeye Trevally are found in all waters of the Pacific with the exception that they are absent from the northern half of the Sea of Cortez.
The Bigeye Trevally is most likely confused with the Pacific Crevalle Jack, Caranx caninus (wider body; dark spot at base of pectoral fin) and the Black Jack, Caranx lugubris (dark fins; dark lateral line).
In some parts of the world such as the Eastern Pacific and the Indian Ocean (including the eastern, northern, and western coastal waters of Australia), the Bigeye Trevallies are popular and prized game fish for recreational anglers. They are abundant at certain times of the year on the Cabo Pulmo Reef, Baja California Sur, where they are seen in massive schools and are of keen interest to scuba divers. They are considered marginal as food fish.
Bigeye Trevally, Caranx sexfasciatus, juvenile. Fish caught from shore at Los Barriles, Baja California Sur, December 2017. Length: 13.2 cm (5.2 inches). Catch courtesy of Mike Rousseau, Maple Ridge, British Columbia, Canada. Photo courtesy of Brad Murakami, Surrey, British Columbia, Canada. Note that the juvenile is virtually identical to the Pacific Jack Crevally but lacks the prominent black spot on the gill cover and has black scutes.
Bigeye Trevally, Caranx sexfasciatus. Fish caught pre-dawn from the shore at Los Barriles, Baja California Sur, December 2017. Length: 46 cm (18 inches). Catch and photo courtesy of Brad Murakami, Surrey, British Columbia, Canada.
Bigeye Trevally, Caranx sexfasciatus. Underwater photo taken in coastal waters off Buena Vista, Baja California Sur, June 2017. Length: 66 cm (26 inches). Photo courtesy of Bob Hillis, Ivins, UT.
Bigeye Trevally, Caranx sexfasciatus. Fish caught from coastal waters off the Gordo Point, Baja California Sur, November 2003. Length: 76 cm (30 inches). Weight: 6.8 kg (15 pounds). Catch courtesy of by Dr. William Inboden, III, Washington, D.C.