The Manta Ecology Project

Very little is actually known about manta rays and this project was initiated to study the behavioural ecology of mantas from observations in the field.

The project began in November 2001 whilst we The Team worked as dive guides on Sea Queen, a liveaboard safari boat which sails around the atolls of the Maldives. High on the diver’s wish list was a dive with manta rays (Manta alfredi is the species we commonly see in the Maldives) so every week a number of dives were made at known cleaning stations in order to observe them.  We were not sure whether we saw the same mantas every week or different ones so we developed an method to identy them individually based on the spot markings based on the ventral side of each manta (see Compare Mantas for more information on identification). 

In 2005 the project was formalised as as a research project under the supervision of Newcastle University. A database was developed to store the bugeoning data on mantas identified. By 2010 there were nearly 2000 mantas recorded and the database continues to grow by about 200 new mantas each year, seen at both established sites which we continue to visit plus a large number of new sites we have identified using our understanding of where mantas go.

It appears that there are fairly fixed populations of mantas in each atoll, but the individuals move around between the various cleaning stations and feeding areas. We have now been sighting the same mantas for 10 years.

The research is part of Anne-Marie's PhD thesis with Newcastle University.

Research is ongoing and currently involves investigations on the differences in physical characteristics and markings patterns between mantas supporting the theory that there are at least two species of mantas: the commonly seen smaller Alfred manta ray (Manta alfredi) and the larger, more pelagic, giant manta (Manta birostris) shown in photo below (photo: John Rochester). There may even be a third species, endemic to the Carribean. 

Manta birostris is found across the world in tropical waters and occasionally travels into colder water with regular reports as far north as New Jersey USA and possibly from Newfoundland and as far south as New Zealand. It grows to at least 6.8m disc width (DW) and has a distinctive bobble just behind its dorsal fin which covers a spine. Manta alfredi is smaller, growing to about 5m DW and is reported mainly from tropical reefs.

 

Current reseach projects include investigation into the social behaviours of individual mantas, including  whether they form groups and close associations and agonistic and heirarchal behaviours between individuals in groups observed. Medium term projects are investigating the movements of both individual mantas and populations of mantas. We have also made initial investigations into visual acuity and colour perception.The study also includes investigations into  feeding behaviour and  cleaning ecology.
 

 

 

We encourage interested divers to come and support our research by joining one of our specific "Research Weeks". Check out the News and Events page for the most up to date information. We are also looking for funding to help us complete a Maldives wide migration studies project. If you can help sponsor this project please contact Anne-Marie

 

 

If you would just like to enjoy some manta pictures see Photo Gallery