There are two species of manta rays. Giant manta rays live in tropical coastal waters near southern Africa, the western and eastern coasts of North America, northern Peru and southern Brazil. Reef manta rays inhabit the Pacific and Indian Oceans close to Japan, Australia, Hawaii, South Africa and Thailand. They tend to stay near coral reefs. Manta rays mainly feed on zooplankton, although giant manta rays also eat fish and crustaceans. Manta rays can live up to 40 years in the wild.
Scientific & Common Names
Manta alfredi is commonly called reef manta ray, Prince Alfred’s ray, inshore manta ray, coastal manta ray and resident manta ray. Manta birostris is commonly called giant manta ray, oceanic manta ray, Pacific manta ray, Pelagic manta ray and chevron manta ray. Recent scientific investigation has found that the two manta rays, traditionally in the genus Manta, should actually be included in the genus Mobula with their close relatives, the devil rays.
Giant manta rays have scaly black or bluish-gray upper bodies and white bellies. Reef manta rays have black upper bodies and white bellies. Both manta ray species have large pectoral fins that resemble wings, fins near their heads that look like horns and a thin tail that does not have a barb. Adult giant manta rays weigh up to 5,300 pounds and measure up to 25 feet long. Adult reef manta rays weigh up to 3,000 pounds and measure up to 15.5 feet in length.
Giant manta rays breed between December and April, while reef manta rays breed between October and January. Females of both species gestate for 12 to 13 months before giving birth to one or two pups. They typically breed once every two to three years. The pups receive no parental care once they are born.
Manta rays are slow swimmers, and they do not maintain their own territories. They are not usually social, although reef manta rays sometimes feed in groups. They use their gills to filter water and trap prey. Giant manta rays leap out of the water and land on the surface, possibly to get rid of parasites on their skin. Both species migrate, but giant manta rays travel greater distances.
Manta rays have been called sea devils or devilfish since the 1800s due to their horn-like fins. They are descended from ancient stingray species, although they lost the tail barb feature long ago.
Giant manta rays and reef manta rays are listed as vulnerable mainly due to fishing. Their slow speed makes them easy to catch, while their slow reproductive rate makes it harder for both species to maintain abundant populations. Manta rays are protected by fishing regulations and bans in certain areas.