Dolphinfish, Coryphaena hippurus
The Dolphinfish, Coryphaena hippurus, whose common Spanish name is dorado, is a species in the family Coryphaenidae, the Dolphinfish, known collectively as dorados in Mexico. This fish is also known by its Hawaiian name, mahi-mahi. Globally, there are only two species in the genus Coryphaena, both found in all Mexican waters of the Atlantic and the Pacific.
The Dolphinfish have elongated compressed bodies with a maximum depth that is less than 25% of standard length. They are a brilliant metallic blue-green dorsally transitioning to golden yellow ventrally with scattered iridescent blue green spots covering their head and body. These striking colors quickly fade to uniform silver upon death. Their anal, caudal, and pelvic fins are yellow and their dorsal fin is blue-green. Juveniles are golden with twelve dark bars on their sides; their caudal fin has white tips and their pelvic fins are black. Adults are sexually dimorphic with males featuring a bony crest on their forehead and a near vertical front snout profile. Females have rounded heads. They have large mouths with numerous small teeth in bands on their jaws and a patch of small oval teeth on their tongue. Their anal fin has a long base with 25 to 31 rays and a concave anterior outer edge extending nearly to the caudal fin. Their dorsal fin has a long base with 55 to 65 rays extending from the nape to almost the caudal fin. Their anal and dorsal fins have no spines or isolated finlets toward the caudal fin. Their caudal fin is deeply forked; their pectoral fins are greater than 50% of the head length; and their pelvic fins are short. Their lateral line is sharply arched over the pectoral fins. They are covered with small smooth scales.
The Dolphinfish are an oceanic pelagic species found predominantly on the surface but also at depths up to 840 feet. They reach a maximum length of 2.3 meters (6 feet 11 inches) and weight of 39.6 kg (87 pounds), the current IGFA angling record caught in Costa Rica waters in 1976. They prefer water temperatures between 21oC and 30oC frequently found in inshore waters. They are voracious predators in search of smaller fish focusing on flyingfish, herrings, jacks, mackerels, mullets, small tuna, and squid. In turn they are preyed upon by marlins, sailfish, sharks, swordfish, tuna, and sea birds. They are known to congregate under floating objects. Reproduction is oviparous and occurs year-round in open waters with each female releasing 58,000 to 1.5 million eggs two or three times a year. They are an exceedingly fast growing species with a lifespan of only four years.
The Dolphinfish is fairly easy to identify due to the coloration and shape of its body, however, it is similar to the Pompano Dolphinfish, Coryphaena equiselis (body depth greater than 25% of standard length; pectoral fins less than half the head length).
The Dolphinfish are one of the major tropical sportsfish of North America. They are routinely caught by recreational anglers on rapidly trolled jigs near the surface or on live fly-lined sardines. Smaller fish travel in schools of up to fifty individuals; if you catch one you can usually catch several. They are inquisitive party animals and will follow hooked comrades to the boat where they too can be caught. Larger Dolphinfish travel as individuals or in pairs. They are considered an excellent food fish for human consumption and a target of commercial fishermen who utilize longlines and purse seine. They are caught globally at a level of 60,000 tons per annum with notable declines recently in the Eastern Pacific. They are sold fresh or frozen with increasing demand and at elevated prices. When sold commercially they are most likely known as mahi-mahi. They have fairly recently been the subject of a series of new conservation measures. In Mexico they are covered by new commercial regulations with area closures, a ban on the use of purse seines, and the recent implementation of a two-fish per day limit for recreational anglers. Note. A small Dolphinfish caught on lightweight tackle on a fly-lined sardine is perhaps one of the most exciting experiences in all of sportsfishing due to the spectacular aerial acrobatics of this fish.
Length versus Weight Chart: A Dorado Weight from Length Conversion Table has been included in this website to allow the accurate determination of a fish’s weight from its length and promote its rapid and unharmed return to the ocean (strongly recommended).