Yesterday was World Manta Day. A day to remind you about the fascinating creatures that glide through the worlds oceans.
Lets dive in and explore the world of the Manta. The Manta is a type of ray belonging to the genus Mobula. There are two species, the larger M. birostris and the relatively diminutive M. alfredi. Manta rays are dorsally flattened cartilaginous fish, meaning they are distantly related to sharks while being flat like other rays and skates. The larger M. birostris can have a "wing-span" of up to 7m (23ft) while the smaller M. alfredi only gets to about 5.5m (17ft) "wing-span" from pectoral fin tip to pectoral fin tip. Mantas are generally black on top and white on the bottom but they do have some white marking on the top to help break up their outline. There have also been reports of some all black Mantas and there is even one official report of a pink Manta near the Great Barrier Reef.
Mantas are unable to swim backwards are unlike most other rays, are unable to pump water over their gills, meaning they must keep moving or else they suffocate. Even when visiting a cleaning station, like some fish do to have parasites removed, they only stop moving for a few minutes before they have to start moving again. They move through the water by using their pectoral fins in a similar manner as birds use their wings.
Mantas are born live, meaning they leave their mother as live individuals rather than as eggs. Gestation takes around 12-13 months and the young are left to fend for themselves with no more protection from either parent. Mantas seem to reach maturity at different times depending on their location but it seems to be when they reach between 3 and 4 meters in size.
A fascinating feature about the Manta ray is that they have the largest brain-to-body size ratio of any other fish. They have also passed the mirror test, which shows a basic level of self-awareness.
They are found in all the worlds tropical and subtropical oceans. The furthest north they have been discovered is off the coast of North Carolina while the furthest south they have been spotted is off the coast of New Zealand.
The greatest threat that the Manta rays face currently is over fishing. Due to the fact that they have such a long gestation period, Manta rays generally don’t breed every year and it can be 2 or 3 years later that they have another brood of 2 or 3 young. Since their breeding rate is so low and most pockets of populations have less than a thousand individuals, fishing can have a large impact. That is why both species have been listed as “vulnerable” on the IUCN list since 2011.