Dive Bali - Manta rays
Manta rays are large beautiful sea creatures that live in warm temperate waters. Their side or pectoral fins have evolved into wide triangular wings which they use to easily propel themselves through the water. With wing spans reaching over 20 feet across, manta rays are one of the largest animals in the ocean. Their broad blanket-like bodies earned them the name manta which means cloak in Spanish.
Relatives
Mantas are members of a group called batoids which include rays, skates and related fish. More specifically, manta rays are members of a larger ray group, scientifically called Myliobatiformes. Rays share common characteristics such as flattened, streamlined bodies and pectoral fins that have evolved large and wide to make up much of their bodies.
Species
Manta rays belong to the family of rays referred to as devil rays, scientifically called Mobulidae. Devil rays share the common characteristic of cephalic or head fins. When unfurled, the fins help to funnel in food and water into the mouth. To make the fins more streamlined, devil rays can roll up these flexible appendages. When furled, these fins were thought to resemble devil horns. When further broken down, manta rays belong to the genus Manta and the species name birostris. Presently, the scientific community identifies all manta rays as one species called Manta birostris. In the past, manta rays were broken into as many as nine species based on their size, coloration, and location. Researchers are working on clearing up this mystery by taking tissue samples of various animals worldwide and comparing mitochondrial DNA. This study, done by Tim Clark of the University of Hawaii, shows that manta rays are one species - Manta birostris. All previous species were shown to be invalid based on genetic sequence analysis.
Colour / Morphology
Many of what were in the past considered different spcies of manta rays are in fact simply different colors of mantas. Similar to how there are different races in humans, mantas can have different color morphologies. In Bali, we typically see mantas that are black dorsally (on their back) with white dorsal "shoulder bars". Ventrally (on their belly) they are mostly white, with a pattern of black spots. While the dorsal coloration is relatively similar in mantas world-wide, ventrally they can be very different. The most extreme difference is the "black mantas". These mantas are predominantly black on their ventral surface, with small spots or patches of white. While both black and white mantas can be seen together in some locations, the white color morphology is always more dominant. However, we know these are not different species because where they are seen together, the white mantas are genetically more similar to black mantas from that area than they are to white mantas from any other area.
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It is time to Dive with the Mantas!
Visit Nusa Penida's Manta Point during the upcoming months and you are sure to find a load of large resident manta rays just hanging out. This is an event that should not be missed.
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see the best dates for Bali Mola Mola sightings in 2007.