The unusual encounters with manta rays in Mallorca continue with a new sighting in Cala Mondragó, where swimmers and divers enjoying the waters off the beach reported seeing the animal, which appeared to be lost. According to reports received by Ultima Hora , the Palma Aquarium and Marineland have been notified so that they can study the case.
This is the third time that a manta ray has been spotted off the coast in less than five days. This is a completely extraordinary phenomenon, as these animals, which are already rare in Mediterranean waters, usually live in the open sea and very rarely approach the coast, and when they do, it is usually because they are disoriented.
As Aniol Esteban, a biologist at the Marilles Foundation, explained, ‘nothing like this has ever happened before. It’s strange and we don’t yet know what is causing it.’ Although the causes have not yet been identified, the expert points out that ‘our hypothesis is that a bacterium or virus is causing a disease that affects their orientation. We still don’t know for sure what is happening to them.’
If you encounter these pelagic animals during a visit to the beach, the authorities recommend that you do not handle the animal, as this could cause serious injury and prevent it from being studied properly. It is also essential to call 112 immediately and notify Palma Aquarium.
Manta rays are large rays belonging to the genus Mobula (formerly its own genus Manta). The larger species, M. birostris, reaches 7 m (23 ft) in width, while the smaller, M. alfredi, reaches 5.5 m (18 ft). Both have triangular pectoral fins, horn-shaped cephalic fins and large, forward-facing mouths. They are classified among the Myliobatiformes (stingrays and relatives) and are placed in the family Myliobatidae (eagle rays). They have the largest brain-to-body ratio of all fish, and can pass the mirror test.
Mantas are found in warm temperate, subtropical and tropical waters. Both species are pelagic; M. birostris migrates across open oceans, singly or in groups, while M. alfredi tends to be resident and coastal. They are filter feeders and eat large quantities of zooplankton, which they gather with their open mouths as they swim. However, research suggests that the majority of their diet comes from mesopelagic sources. Gestation lasts over a year and mantas give birth to live pups. Mantas may visit cleaning stations for the removal of parasites. Like whales, they breach for unknown reasons.
Both species are listed as vulnerable by the International Union for Conservation of Nature. Anthropogenic threats include pollution, entanglement in fishing nets, and direct harvesting of their gill rakers for use in Chinese medicine. Manta rays are particularly valued for their gill plates, which are traded internationally. Their slow reproductive rate exacerbates these threats. They are protected in international waters by the Convention on Migratory Species of Wild Animals, but are more vulnerable closer to shore. Areas where mantas congregate are popular with tourists. Only a few public aquariums are large enough to house them.