Majestic Manta Rays have been a diver favorite for decades due to their playful and curious nature. Manta and Mobula rays both belong to the family mobulidae, a group of planktivore (plankton eating) rays. Out of the eleven ray species in the mobulidae family, there are only two types of Mantas: reef dwelling and the infamous oceanic Manta. In the past ten years, dedicated scientists have worked together to unravel the mystery of the manta, leading them to realize that Manta numbers are quickly dwindling. Asian markets are famous for advertising various rare and beautiful animal body parts as ancient medicinal cures, though there is no modern science to back their claims. Their latest victim is not one found in the ancient scrolls, but a figment of fisherman’s imagination, which they turned into profit – Manta Rays.
In order to understand how important protecting Mantas are, one must understand the beauty and indescribable grace which they possess. Oceanic manta rays can weigh up to 2 tons and have a wing span of 10 feet and live upwards of 100 years! In addition to their natural curiosity, Manta’s are incredibly social animals. Often times, they will form what looks like conga lines, as there is a line leader which the others follow as they zoom through reefs and open ocean – quite a spectacular display. The anatomy of a Manta Ray is unique because gills function as lungs; therefore, these rays must constantly move forward to provide a constant stream of Oxygen rich water flowing through the gills.. In today’s world of industrial fishing, the size and anatomy of both Mantas and Mobulas make them prone to be caught as by catch, or entangled in fishing gear. When entangled in long lines or gill nets, Mantas usually drown because they are deprived of flowing seawater which they require to respire and stay alive. High by catch and entanglement rates are just the first of Manta’s problems concerning negative human induced effects.
Mobula rays display very similar characteristics as the larger Manta rays, the main difference being size and shorter migrations. The habitat of these rays’ range from South Carolina to New Zealand and everywhere in between! Both species can be spotted near reefs, and larger Manta’s are more notably seen swimming along productive coastlines, seamounts, and upwellings. Upwellings are places where there is a sudden drop off which creates a circulation of nutrient rich water rising from great depths to the surface and pushing the nutrient poor water to the bottom. This provides an ideal location for zooplankton to thrive – Manta favorite! Manta rays have the absolute highest brain to body ratio of any fish! This means that they are highly intellectual animals, even more so than some marine mammals. Such an intelligent creature does not, under any circumstance, deserve to be harvested and die for their gill plates. Sadly, Manta and Mobula rays are being caught and dried every day.
Shark Finning is the lucrative and disgusting practice of catching sharks and then slicing off each fin until all that remains is the body which they throw overboard. The shark fin trade, though illegal in some countries, takes place globally but the fins eventually land in Asian markets. Fisherman relentlessly caught them, though warned of the negative ecological impacts, and eventually the waters ran dry. This trade has severely decreased populations of multiple shark species, but the fisherman and Asian markets still needed to make money so they began harvesting manta ray gills. They were already catching rays on accident so it was easy for them to switch to intentionally catching the rays, where they would then cut out their gills and leave them to dry out. Unlike shark finning, which was rooted in ancient traditions, the Asian markets innovated medicinal purposes to sell manta ray gills. Within the last ten years, is the first record of these gills being sold in the markets and sellers are unable to reference a single ancient scroll containing medicinal purposes for the gills. Sellers claim that gill plates can cure acne, the flu, measles, colds, and many more illnesses. The manta trade only developed as a “back-up plan” in case sharks declined so much so that they were unable to catch them. However, the manta trade has grown so much and become so profitable that it shows no signs of decline. This is bad news because the manta’s populations have been on the decline in the last decade, coinciding with the increase in the gill plate trade.
Both manta and mobula rays are listed as Vulnerable under the IUCN Red list, establishing that the species is on the decline and increased protection and research is needed. Manta ray research has been able to put these magnificent creatures on two important, international protective lists: CITES and CMS. CITES stands for Convention of International Trade in Endangered Species, which makes it illegal under almost any circumstance to fish and sell manta ray gill plates; however Mobula rays are not yet included in this legislation. CMA stands for Convention on Migratory Species, which 116 countries are a part of, and have recently given Oceanic Manta rays increased protection. Oceanic Mantas and their habitats are now strictly monitored and protected under this new legislation. With the aid of researchers from around the world, these rays are better protected against the gill plate trade; however, mobula rays protection is greatly needed if the trade is to be completely stopped.