![]() ![]() Average age at sexual or reproductive maturity (female).Manta ray pups are between 1.1 and 1.4 meters when they are born. ![]() Pups are born wrapped up by their pectoral fins, but soon after become free swimmers and fend for theirselves. The gestation period of Manta birostris is 13 months, after which females give birth to 1 or 2 live young. However, after the second male the female usually swims away leaving behind the other courting males. The male will then swim away rapidly and the next male will repeat this same process. The male will then insert his clasper in the cloaca of the female and insert his sperm, this usually lasting around 90-120 seconds. He arranges his body under that of the females. This courtship will last for about 20-30 minutes at which point the female decreases her swimming speed and a male will grasp one side of the female's pectoral fin by biting it. The males swim closely behind the tail of the female at faster than usual speeds (9-12km/h). Manta rays gather in large numbers during this season, where several males will court a single female. Mating takes place in tropical waters (26-29 degrees Celsius), and around rocky reef areas from 10-20 meters in depth. The mating season of sexually mature manta rays occurs from early December to late April. Manta birostris are sexually mature at 5 years of age. ( "Manta Rays", 1989 Acker (MRBH), 2001 Bigelow and Schroeder, 1954) The skin of manta rays is rough and scaly, like that of most sharks. These rays vary in color from black to grayish blue along the back, and a white underside with grayish blotchs that have been used to identify individual rays. One of the distinct features of manta rays, and of the class Chondrichthyes, is that the entire skeleton is made of cartilage, which allows for a wide range of motion. The largest ever recorded was 9.1 meters. Manta rays show little dimorphism between the sexes with wingspan in males ranging from 5.2 - 6.1 meters and females ranging from 5.5 - 6.8 meters. Atlantic manta ray pups weigh 11 kg at birth and their growth is rapid, with pups virtually doubling the body width from birth through the first year of life. Manta rays also have a short, whip-like tail that, unlike many rays, has no sharp barb. The gills are located on the underside of the body. They have two cephalic lobes that extend from the front of the head and a broad, rectangular, terminal mouth containing small teeth exclusively in the lower jaw. Manta rays are easily reconized in the ocean by their large pectoral "wings." Manta birostris have no caudal fins and a small dorsal fin. ( Acker (MRBH), 2001 Bigelow and Schroeder, 1954) Atlantic manta rays stay closer to shore in the warmer waters where food sources are more abundant, but occasionally can be found further from shore. Manta birostris, unlike most other rays, are found near the surface of the ocean and to depths of 120 meters. ( Bigelow and Schroeder, 1954 FishBase, 1999 OceanLink, 1997) Manta rays are found in tropical and warm temperate coastal regions of the world's oceans, generally between 35 degrees north and south latitude, including the coasts of southern Africa, ranging from southern California to northern Peru, North Carolina to southern Brazil, and the Gulf of Mexico. ![]()
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