Reef Manta Ray, Manta alfredi

The reef manta ray is found in shallow coastal waters around the Indo-West Pacific, The Red Sea, South Africa, Thailand and Western Australia. It can also be found around the southern islands of Japan and from Eastern Australia to French Polynesia, including the Hawaiian Islands. It will normally stay within a few miles of the shoreline around coral and rocky reef areas.

The reef manta ray is the second largest of the ray family, reaching a maximum length of up to 16.4 feet and maximum wingspan of 18 feet, typically the reef manta ray has a wingspan of 9.8 – 11.5 feet. Generally this species of ray is wider than it is long and can weigh up to 1.5 tons. The female of this species is larger than the male.

The wings are triangular in shape attached to the body from just behind the head to the slender whip-like tail and extend outward to a point. This species has no spine or cartilage at the base of the tail as with most other species of ray; however some will have a small hump while others will have a slight depression.

The mouth of the reef manta ray is rectangular and contains 6 – 8 rows of small cusped teeth on the bottom jaw with a total tooth count of 900 – 1500 teeth, while the top jaw is lacking rows of large teeth. Extending down from each side of the mouth are large paddles for guiding food into the mouth as it swims. The eyes are set on the side of the head and large gills are located on the bottom side of the ray.

There are many different color variations of the reef manta ray but it is mainly black backed with a white underside. A white “Y” shaped patch extends from the top of the head fading into the black back, and several dark blotches are on the underside.

The reef manta ray will gather in groups to feed on tiny plankton that is filtered through sponge-like tissues between the gills. Often a fish called remoras will attach itself to the ray and collect food fragments which fall as the manta ray eats.

Males will compete for the attention of the female reef manta by chasing her around the reef and the victor will often grab the female by the left wing. Mating is done belly to belly with internal fertilization. After the egg is fertilized, it will develop for a year before it will hatch inside the female; the young is born live, rarely more than one, with at least two years between births.

The reef manta ray species is declining in numbers, so it has been put on the endangered species list as vulnerable. Some countries have banned the fishing of the reef manta ray, including Hawaii, Maldives, and The Philippines. Western Australia protects the ray in marine parks, and in the western Pacific Ocean around the isle of Yap, a designated protection area has been established.

Kingdom: Animalia

Phylum: Chordata

Class: Chondrichthyes

Subclass: Elasmobranchii

Order: Rajiformes

Suborder: Myliobatidae

Family: Mobulidae

Image Caption: Manta ray (Manta birostris) at the Fushivaru Thila cleaning stations, Lhaviyani Atoll in the Maldives. Credit: asands/Wikipedia (CC BY-SA 2.0)