Manta birostris; "manta" is from a Spanish word meaning blanket

Description

The largest member of the ray family, the giant manta is up to 22 feet across and weighs up to 3,500 pounds. Aside from its size, it can be distinguished from other rays by its large triangular pectoral "wings" and paddle-like lobes extending in front of the mouth. There are no caudal fins, and a small dorsal fin. It has a short, whip-like tail that, unlike many rays, has no sharp barb. The eyes are on the sides of the head, and the gills are on the underside of the body.

Manta rays vary in color from black to grayish blue along the back, and have a white underside with grayish blotchs that have been used to identify individual rays. There are also large white "shoulder patches" on the back that are usually triangular- or chevon-shaped, and there may also be white patches on the tips of the pectoral fins.

Distribution and Habitat

Manta rays are found in tropical, sub-tropical, and temperate waters worldwide. They tend to stay stay closer to shore in the warmer waters where food is more abundant, but can be found in the open ocean. Although capable of diving to depths of over 3,000 feet, they spend most of their time at depths of less than 390 feet.

Manta rays are highly migratory, and commonly travel across thousands of miles of open ocean in search of food sources.

Diet

Manta rays filter water through their gills and organisms in the water are trapped by a filtering device, which consists of plates in the back of the mouth that are made of pinkish-brown tissue that span between the support structures of the gills. Plankton make up the vast majority of the diet, but small fish and crustaceans are also taken. The manta's teeth serve no function during feeding.

Reproduction

Courtship can last for days, with several males following a single female, competing for the right to mate. Eggs are fertilized and develop internally, with one or two pups being born after about twelve months.

Pups are able to fend for themselves almost immediately, and may double in size within their first year. Sexual maturity is reached at about five years, and average lifespan in the wild is over forty years.

Behavior

Manta rays are generally solitary, but loose groups will form where there is abundant food, as well as for mating.

Manta rays can leap up to seven feet out of the water. Whether this is done for fun, to get rid of skin parasites, or both, is unknown.

Although they are generally leisurely swimmers, especially when feeding, manta rays are capable of achieving great speed.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class Chondrichthyes
order Rajiformes
family Mobulidae
genus & species Manta birostris

Questions or comments about this page?