Dr Andrea Marshall has classified manta rays into two different species: Manta birostris and Manta alfredi. In 2008, she was the first person in the world to complete a PhD on manta rays.
Manta birostris are oceanic and frequently migrate. They can be found in the Atlantic, Indian and Pacific oceans. They can grow up to seven metres across, have their belly markings mainly located under the gill slits and have a calcified lump on the base of their tail. Manta alfredi are smaller and commonly sighted closer to shore, often in groups. This species is widespread across the Atlantic, Indian, and Pacific oceans, with their markings evident across their whole belly. Currently, Andrea is working on identifying a third manta species!
Below are some of Andrea’s favourite manta diving destinations:
“Southern Mozambique is the only known destination worldwide where divers can regularly dive with both species of Manta, even at the same time! This unlikely destination boasts one of the world’s largest catalogued populations of manta rays and the resident population can be encountered throughout the year”. The Marine Megafauna head office is here in Tofo.
“Once a year during the monsoon season (between May and October), reef manta rays gather in staggering numbers to exploit large plankton blooms that are captured in this tiny horseshoe shaped lagoon known as Hanifaru. As many as 200 individual rays can be seen at the same time sweeping back and forth across the lagoon in dramatic feeding chains.”
“The reef manta rays come out in force in Komodo, with monster aggregations of up to 80 individuals seen at feeding sites like Karang Makassar in the north. Year-round this is a hotbed of activity from cleaning and feeding to courtship and mating! Pregnant manta rays are also regularly seen in the park.”
“The Revillagigedo Archipelago is located a whopping 400 kilometres south of Cabo San Lucas, making it one of the most remote diving destinations on the planet.” The friendliest giant mantas in the world - sometimes melanistic (mainly black) or leucistic (predominantly white) - frequent between November and May.
“Raja has some of the most pristine coral reefs still on Earth. It also happens to be the home of both species of manta ray, living in mosaic sympatry throughout the region. Found at particular aggregation sites throughout the park, you can encounter reef mantas swimming lazily around shallow sandy channels. Giant mantas also visit deep water coral reefs.” The best time for mantas is December to April.
“The mantas are relatively small at this location but there are plenty of them and they are incredibly relaxed and tolerant. Opt for an early morning dive at Manta Point followed by a lovely picnic lunch then a good few hours of snorkelling with feeding mantas at ‘Big and Little Manta Bay’.” Sightings are year round. Marine Megafauna has a location on the island of Nusa Lembongan.
“Arriving not in tens but hundreds to this part of the coast, these planktivorous giants spend a couple months of the year (July to September), vacuuming up the surface slicks of snapper spawn to feed their insatiable diets before moving off into the depths of the Gulf of Mexico. While you cannot dive with either of the species at this location because of strict codes of conduct, you can still snorkel along side dozens of distracted feeding mantas making this one of the best locations for up-close encounters.”
“This tiny island is considered by many to be one of the top places to dive with reef manta rays in the Pacific. Yap boasts one of the only year-round populations of manta rays and they are virtually accessible all of the time. Yap remains one of only a handful of places on earth where manta rays are well and truly protected by law.” They can be seen all year but October to March is reproductive season.