Transcript:

Today on Animal Fact Files we’re discussing the mahi mahi. These fish are also known as dolphinfish, however that common name can be misleading. They're in no way related to the similarly named mammals called dolphins. In fact, no one is entirely sure why they got the common name dolphinfish. Perhaps it's their speed, like a swimming dolphin, perhaps it's their blue sheen or their tendency to stay near the surface, especially close to floating objects. In whatever case, dolphinfish are not mammals.

The name mahi mahi is Hawaiian in origin and means "strong." There are technically two mahi mahi species, the common dolphinfish and the pompano dolphin. The pompano dolphin's body depth, which is the measurement between the highest point on their back and lowest point on their body, is more than 25% the fish's body length, in common dolphinfish this measurement is less than 25%. Of course, if you don't feel like pulling out a ruler, you can always just look in their mouth. These fish have tooth patches on their tongue. The common dolphinfish has a small, oval tooth patch, while the pompano dolphinfish has a broad, rectangle tooth patch.

Mahi mahi are pelagic fish meaning they spend most of their time out at sea. They're most often found in tropical and subtropical marine waters around the world. They're attracted to floating objects, such as large swaths of sargassum, which is a type of seaweed. Although they're most often away from shore, they don't dive deep. These fish are almost exclusively found no deeper than 280 feet (85 km) below the waves. They prefer to stay near the ocean's surface where there's light and plenty of food. These fish eat small fish and juveniles of larger fish such as tunas. They also consume crustaceans and cephalopods!

Mahi mahi are fast, agile swimmers capable of reaching speeds over 50 miles per hour (80 km/h), but even this isn't fast enough to keep them away from predators such as tunas and marlins. It's not uncommon to find a mahi mahi speared by a marlin's pointed snout! Mahi mahi are also eaten by sharks, seabirds, and porpoises. Considering they average about 3 feet in length (91 cm) and 30 pounds (14 kg) in weight– although record fish were double these metrics– mahi mahi make a great meal for oceanic predators and humans alike.

Smaller mahi mahi travel in shoals of up to 50 individuals, however the largest members are solitary or travel in pairs. They have a single dorsal fin that extends the length of the back to their forked tail fin. Male dolphinfish can be told apart from females by the large, bony crest that forms on their head. A female's head profile is more round. These fish are colorful, displaying a metallic shimmer of blues, greens, and yellows. Juveniles may even display bars along their side, however these fade with age. They're short-lived fish with an approximately four year long lifespan. 

Mahi mahi most frequently spawn during the warmest parts of the year, although in tropical climates they may breed year round. They find floating debris as a means to congregate, and their eggs and larvae are on their own from birth. Fertilization is external, and the fry float through the water column as they grow. It only takes about 4 to 5 months for mahi mahi to reach reproductive maturity. They begin spawning once they're only about 8 inches (20 cm) long! These are far-moving fish who can travel upwards of 1,800 miles (3,600 km) in a single month!

For more facts on mahi mahis, check out the links below. Give a thumbs up if you learned something new today. Thank you to our Patrons SpikeSpiegel93, Dad, and everyone else for their support of this channel! And thank you for watching Animal Fact Files!