Dorado Fish: Mahi-Mahi, Golden Dorado or Sea Bream?

Dorado almost always means the mahi-mahi, Coryphaena hippurus, a fast, brilliantly coloured fish of the open ocean. Wikipedia explains the three names: mahi-mahi is Hawaiian for 'very strong', dorado is Spanish for 'golden', and dolphinfish is the English name, used to avoid confusion with dolphins, which are mammals. Central America Fishing adds that Atlantic anglers tend to say dolphin, Pacific anglers mahi-mahi and Latin American anglers dorado.

Two other fish share the word, which is why people ask whether dorado is the same as sea bream:

• Golden dorado, Salminus brasiliensis: a freshwater predator of the Paraguay, Paraná and Uruguay river basins in South America, golden as an adult with a large head and sharp teeth. Wikipedia gives the largest recorded at 1.3 m and 34 kg
• Dorada, the gilt-head bream Sparus aurata: a Mediterranean and eastern Atlantic sea bream with a golden bar between the eyes, up to 70 cm but usually 35 cm, and mostly farmed, with Turkey and Greece the leading producers (Wikipedia)

So dorado on a menu in Mexico or Costa Rica is usually mahi-mahi, while dorada in Spain is sea bream. They are not the same fish.

• Colour: brilliant golden sides with bright blues and greens; Central America Fishing calls it the most colourful fish in the sea
• Colour change: out of water the colours shift quickly, then fade to a muted yellow-grey after death (Wikipedia). Photograph the fish as soon as it is landed if you want to record its colour
• Head shape: mature males, called bulls, have a tall, blunt, almost vertical forehead; females, called cows, have a rounded head (Wikipedia, Central America Fishing). Bulls usually outweigh cows
• Look-alike: the pompano dolphinfish is the only other member of the family (Wikipedia), and it is much smaller

The FishLens app identifies a mahi-mahi from a side-on photo.

Wikipedia gives typical catches of 7 to 13 kg (15 to 29 lb) at about a metre long; fish over 15 kg are uncommon and over 18 kg exceptional. Central America Fishing puts typical catches at 10 to 30 lb, says mature adults can pass 50 lb, and lists the world record as 87 lb, caught in Costa Rica in 1976.

They grow fast and die young. Wikipedia says they mature within their first year, at 4 to 5 months, females spawn two to three times a year with 80,000 to 1,000,000 eggs each time, and the maximum lifespan is five years. Central America Fishing gives a lifespan of 6 to 7 years and growth of up to two inches a week in the first year. The sources differ on lifespan; both describe a short-lived, fast-breeding fish.

Mahi-mahi is a widely eaten food fish. Wikipedia describes the flesh as grey-white when raw, cooking to white with a clean, mild flavour, and the US Food and Drug Administration lists mahi-mahi as a 'Good Choice' in its advice on eating fish, one category below 'Best Choices'.

The risk to know about is scombroid poisoning, also called histamine fish poisoning. The Minnesota Department of Health lists mahi-mahi among the fish that cause it: bacteria turn a natural substance in the flesh into histamine when the fish is not kept cold. Histamine is not destroyed by cooking or canning. Its advice is to keep fish at 41 F or colder from capture until cooking and to avoid fish that smell bad. Symptoms, which can start within minutes to a few hours, include tingling or burning around the mouth, a flushed face, sweating, nausea, vomiting, headache, a racing heart and rash. Contact a doctor if symptoms are severe.

Central America Fishing names Costa Rica and Panama as the best places, on both coasts, and says November and December bring the largest adults, while May to September gives good numbers of smaller fish. Methods it lists include trolling ballyhoo, rigged naked or with skirts, circle hooks, and casting poppers and stick baits at floating debris, where dorado gather. They feed on squid, flying fish, small bonito and mackerel, and Wikipedia records swimming speeds of up to 50 knots.