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Not just a huge collection of Shark Pictures: Elasmodiver.com contains images of sharks, skates, rays, and a few chimaera's from around the world. Elasmodiver began as a simple web based shark field guide to help divers find the best places to encounter the different species of sharks and rays that live in shallow water but it has slowly evolved into a much larger project containing information on all aspects of shark diving and shark photography.

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MANTA RAY

View all available Manta Ray Pictures in the Shark Pictures Database

Common Names: Manta Ray, Pacific or Atlantic Manta ray, Devil ray.

Latin Name: Manta birostris

Family: Mobulidae

Identification: Immense size (the largest of all the rays). Terminal mouth has well developed, flexible cephalic lobes. Single dorsal fin anterior to tail. Small bump at trailing edge of dorsal. Tail thin and less than body length.

Black Manta colour variation: Dorsum completely black. Cephalic lobes black. Ventrum black or mostly black with brilliantly contrasting white central patch.

White Manta colour variation: Predominantly black dorsum with symmetrical white patches sometimes forming a chevron across the shoulders. Wing tips sometimes fade to white. Ventrum white or pale often with dark symmetrical patches that also sometimes form a chevron pattern.

Size: Maximum width 7m. Disc width at birth 1.2m. Unsubstantiated reports stretch up to 9m.

Habitat: Oceanic offshore waters. A regular visitor to sea mounts and off shore islands where plankton is forced to the warmer surface layers.

Abundance and distribution: Circumtropical and less commonly circumtemperate. I have one report from as far north as Vancouver island in Canada from the 1960's. 

Behavior: Manta rays are often seen where plankton is concentrated. They unroll their cephalic lobes and use them to channel plankton into their mouths. Occasionally they can be seen barrel-rolling in the water column when feeding. They may also breach; perhaps to rid themselves of parasites. Seen singly or in aggregations where food (plankton) is abundant. "Warm blooded" i.e. able to sustain higher temperatures within their bodies and chondocraniums (brains) relative to the ambient water temperature. This may be a tool for maintaining constant muscle function whilst moving in and out of thermoclines. Has been known to travel long distances and congregate for coral and fish spawning events.

Reproduction: Ovoviviparous. Gives birth to one or two pups.

Conservation Status: Considered 'Vulnerable' by the IUCN.  Quote: "Currently this species has a high value in international trade and directed fisheries exist that target this species in what is certain to be unsustainable numbers. Artisanal fisheries also exist that target this species for food and medicine. Individuals are also taken as bycatch in everything from large-scale fisheries to shark control programs/bather protection nets.
The rate of population reduction appears to be high in several regions, as much as 80% over the last three generations (approximately 75 years), and globally a decline of 30% is strongly suspected. Sustained pressure from fishing (both directed and bycatch) has been isolated as the main cause of these declines. Certain monitored subpopulations appear to have been depleted, such as in the Philippines, Indonesia, and parts of Mexico and are believed to be decreasing in other areas such as India and Sri Lanka as a result of sustained pressure from fishing. Of particular concern is the targeting of this species at critical habitats or well-known aggregation sites where numerous individuals can be targeted with relatively low catch-per-unit-effort."

Citation: Marshall, A., Bennett, M.B., Kodja, G., Hinojosa-Alvarez, S., Galvan-Magana, F., Harding, M., Stevens, G. & Kashiwagi, T. 2011. Manta birostris. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>.

Photographs: Revillagigedo Archipelago (Isla San Benedicto and Isla Socorro), Mexican Pacific.

Similar species: Manta birostris was once thought to be split into many regional species. There are currently just two valid species but more may eventually be described. Manta alfredi is visibly identical to Manta birostris but it lacks the small bump at the back of its dorsal fin. It also has a smaller maximum size of 5.5m

Reaction to divers: Curious, often approaching divers and in some areas allowing contact (belly rubbing) which it seems to enjoy. Will sometimes play (somersault) in the divers bubbles. Moves away when pursued. Will tolerate riding for short periods but this behaviour from divers is not condoned! Mantas come to plankton rich seamounts to feed and if stressed and forced to leave this impacts on their ability to get the sustenance they need. 

Diving logistics: This is a commonly seen ray in various locations around the tropics and subtropics. It can be reliably encountered at Socorro and San Benedicto Islands south of Baja in the Revillagigedo Archipelago. This is an excellent area to observe and interact with giant oceanic mantas because the water is relatively clear and the mantas are exceptionally friendly. Contact bigfishexpeditions.com for information about trips to Socorro.

Probably, the largest aggregations of mantas can be found in the Maldives although the visibilty in the area where the mantas congregate can be very rich in plankton.

Other diving locations submitted by readers:

Further reading:

       Reef Sharks and Rays of the World. Scott W. Michael. Sea Challengers.

       Sharks and Rays - Elasmobranch Guide of the World. Ralf M. Hennemann. IKAN.  

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