The Hawaiian name for dolphinfish—mahi-mahi—means strong. The mahi-mahi is difficult to reel in when caught, making it a favorite of sport fishermen. It is also a tasty fish, it is called dorado from the Spanish word for gold.
There are two species of dolphinfish that are so similar that the both are referred to by their more popular common name mahi-mahi. The common dolphinfish (Coryphaena hippurus) and pompano dolphin (Coryphaena equiselis) can be difficult for non-experts to differentiate, with the primary difference being that pompano dolphin are smaller in depth and length and the larger dolphinfish. Adding to the confusion, both species tend to live in the same habitats meaning that where you find one, you will likely also find its closest relative.
The larger of the two dolphinfish, the common dolphinfish, can grow to up to 6 feet in length and weight between 80 to 90 pounds. Dolphinfish are bright in color, often displaying brilliant greens and blue colorations. They also are known for their blunt, flat head.
No one knows exactly how the mahi mahi got the name dolphinfish. It may be because mahi mahi are often seen swimming with dolphins. Like the larger dolphin, flat-headed dolphinfish tend to jump out of the water when chasing their prey. Another reason may be that after death, dolphinfish lose their bright colors, turning gray, similar in color to the dolphin. Early fishermen may have misidentified the dead fish when they were brought onto boats.