![]() Overfishing has the real potential to wipe out large numbers of giant oceanic mantas due to the fact that they live so long and reproduce so little. ![]() Their size make them particularly susceptible to entanglement in fishing nets even when they are not voluntarily fished out. Their gills is still in high demand mostly by the traditional chinese medecine market. The Manta Trust and Marine Megafauna foundations are both working globally to research and protect the mobulae family and their habitats. The International Union for Conservation of Nature (IUCN) declared manta rays as ’vulnerable’ in 2011. All of this combined make their reproduction quite slow! ![]() The mother will usually have two years elapse between pregnancies. Manta-mums usually carry only one pup, but 2 pups have already been recorded. They are born independent after a 12-13 months gestation period. One can only speak of regional populations, which are monitored separately.Manta rays can live as long as 50 years and are ovoviviparous, which means that they start development in an egg and hatch within the mother's body. The exact number of giant oceanic manta rays is unknown and difficult to estimate. However, there is no global programme to protect the species or to prevent its extinction. Since 2011, the giant oceanic manta rays have been listed as one of the most vulnerable species. There’s evidence that they rarely reach depths of over 1,000 metres. They are most often found in shallow waters at depths of 1 to 40 metres near coastlines or coral reefs that are rich in food, but they have also been seen at depths of over 120 metres. Occasionally, giant oceanic manta rays invade shallow bays and estuaries. They live mostly near continents and islands, such as the coast of South Africa, around Madagascar, between the coasts of southern California and northern Peru, from the coast of North Carolina in the US to the south of Brazil, anywhere in the Gulf of Mexico, but can also be seen offshore. Giant oceanic manta rays occur in the tropical seas and oceans of the world from 35 degrees north latitude to 35 degrees south latitude. The rear of the body has a long thorn-shaped tail without a sharp needle at the end. There are also dark spots on the body that are different for each specimen. The ray’s belly is of milky white colour that acts as a disguise when viewed from below. The fins are remarkably elastic on both sides, allowing a maximum grip. The giant oceanic manta rays swim by moving their two fins, resembling a flying bird. The head is at the front of the body with a pair of eyes that can observe single objects independently of the other eye behind the cheeks. The giant oceanic manta ray’s body has a hydrodynamic shape that reduces water resistance to movement. There are only minor differences between the sexes. Large specimens live for about 20 to 25 years, although the maximum life span is not yet known. The maximum registered weight is 1,400 kg. Thus, giant oceanic manta rays are broad rather than long. They grow to about 3 to 5 metres in length, with a disc size of about 7 metres, but specimens with a range of more than 9 metres have been observed. Giant oceanic manta rays, like sharks, do not have a solid skeleton but bones consisting of flexible cartilage.
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