Manta rays can be found throughout the worlds tropical and semi-tropical oceans, common in shelf waters where deep upwellings bring plankton rich currents to these large filter feeders. Their size means that they have few natural predators, with large sharks (e.g. Tiger and Bull sharks) and possibly Orcas (Killer whales) posing the greatest natural threat. However, a mantas flattened body affords them some protection by making it very difficult for a predator to get its teeth into the vital organs, often they escape with just a bite on the wing. While these injuries are severe, manta rays appear to have a remarkable ability to heal and it is common to see individuals in the Maldives with old shark bites on their pectoral wings, or even whole sections of a wing missing.

For generations, where manta rays and their smaller relatives, the Mobula rays, have existed around the world people have fished them for their oily livers, flesh and their

Swimming with manta rays is an awesome experience, however divers and snorkellers should always ensure that they interact responsibly when encountering them. They are curious and social animals who will often approach you, this should always be on their terms and chasing or attempting to touch or ride a manta will frequently result in them being frightened off. One the best places to observe mantas is at cleaning stations, while these locations offer excellent close encounters it’s important that divers never swim directly onto the cleaning station or inhibit the path of the mantas. By following these simple rules we can ensure that your dive is both memorable for you and respectful towards the manta rays.

tough abrasive skin. This type of local subsistence fishing has always been sustainable, with the fisherman taking only a very small percentage of the population. However in the 1990s large scale commercial fisheries began to appear, targeting these rays for their fins, branchial filaments and even as just bait, having a devastating effect on the local populations.

In Mexico and the Philippines populations have been decimated, with only a handful of manta sightings now reported each year in the fished areas whereas few decades ago their numbers were plentiful. In 1998, a few coastal islands in Indonesia switched from a local subsistence manta fishery to a new type of large scale commercial fishing to supply a new demand for dried manta branchial gill filaments, which are ground into powder and sold into the Asian medicine market. Before 1998 it was estimated that the local fishermen in these waters caught between 300-400 mantas per year in total. In 2002 the World Wildlife Fund (WWF) sponsored a survey to assess the impact of these commercial branchial fisheries; they reported a huge increase in the catch numbers of up to 2,400. Already in just a few years it appears that the local population has been decimated with local fishermen having to move further to find mantas.

Target fisheries for manta and mobula rays also currently exist in several other countries around the world, with substancial numbers being caught in Mozambique, Madagascar, India, Sri Lanka, Brazil, and Tanzania every year.

Indirectly manta and mobula rays often fall victim to nets as unintentional bycatch in a number of other fisheries. Tuna purse-seine nets, drift nets and long lines, used for shark fin fishing, frequently catch these rays which then quickly die as they need to keep swimming in order to ‘breathe’. Each year in South Africa and other parts of the world, manta rays and many other marine animals (such as dolphins, whales and turtles) get indiscriminately entangled and killed in large numbers where shark nets are used to protect the beaches.

All of the above manmade threats are especially difficult for manta ray populations to recover from due to their life cycle. Slow growth and maturity rates, long gestation periods, infrequent birthings and small litter sizes mean that this species is particularly vulnerable to exploitation. Where large scale fisheries have occurred it will take many of our lifetimes before these populations recover, if ever.

This vulnerability means that manta rays are listed as ‘near threatened’ by the World Conservation Union (IUCN) and much scientific research is still needed to properly assess their status worldwide. Almost nothing is known about their population ecology, use of critical habitat, movements or reproduction, all of which are

protection and a thriving dive tourism industry which they help to support. The income which is generated from manta diving in the Maldives alone is calculated to be in the millions of dollars annually, bringing much more money to the country than any manta fisheries could.

important if we are to accurately asses the state of the species. Some countries have taken steps to enforce their own national protection of manta rays; the Maldives has a large population of mantas which have complete

Manta finning in the Maldives

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