Island Jack, Carangoides orthogrammus
The Island Jack, Carangoides orthogrammus, whose common Spanish name is jurel isleño, is a very rarely seen member of the Jack or Carangidae Family, known collectively as jureles and pámpanos in Mexico. There are twenty-two global members of the genus Carangoides, four of which are found in Mexican waters, two in the Atlantic and two in the Pacific.
The Island Jacks have deep elongated oval compressed bodies with a depth that is 35 to 40% of standard length. They are overall silvery in color with pale green dorsally and white ventrally and have two to seven large elliptical yellow spots with brown borders along their body close to the mid-line. Some fish have nine or ten dark vertical crossbars that run from the head to the caudal fin. Their soft anal, soft dorsal, and caudal fins are brilliant blue and their other fins are pale green. Their color changes drastically upon death as they darken to a dusky green to gray-green dorsally and silvery-green ventrally and their yellow spots become brown. Their head profile is high and gently sloping. They have a blunt snout, eyes set at snout level, and thick lips. They have 30 to 31 gill rakers. They have short anal and dorsal fin lobes. Their spinous dorsal fin is low and their pectoral fins are long. They have 19 to 31 small scutes. The curved section of their lateral line is only slightly arched. Their body is covered with small scales.
The Island Jacks are a circumtropical pelagic species found in and around rocky reefs at depths up to 625 feet. They reach a maximum length of 75 cm (30 inches). The Island Jacks are a poorly studied species and very little is known about their behavior patterns.
The Island Jack has a wide global distribution being found in the Atlantic Ocean from East Africa to the Americas and in the Indian and Pacific Oceans. In Mexico the the Island Jack has a limited distribution being only found around the oceanic islands and the extreme southern portion of the Baja, from just into the Sea of Cortez (documented by a fish that I caught) to as far north as Todos Santos in the Pacific.
The Island Jack can be confused with the Bluefin Trevally, Caranx melampygus (blue anal, caudal, and dorsal fins; small blue and black spots on sides).
In Mexican waters the Island Jacks are exceedingly rare, therefore of limited interest to most, however, in eastern, northern, and western coastal Australia they are targeted by surf fishermen. The fish photo below of a Los Cabos fish can also be found on page 331 of a book entitled “Fil-O-Fish”, a waterproof handbook of Australian fish where this fish is known locally as the Thicklip Trevally.
Island Jack, Carangoides orthogrammus. Fish caught from coastal waters off Point Palmilla, Baja California Sur, October 2017. Length: 51 cm (20 inches).