Almost nothing is known about the sensory and learning abilities of manta rays, however my recent neuroanatomical research also demonstrated that the giant manta rays (Manta birostris) have the largest brain of all fish. These aspects of their biology are difficult to study in their natural habitat, because their presence is often unpredictable and it is hard to create a well-controlled environment. Manta rays have demonstrated curiosity and interest toward divers at many tourist locations, but the effects of human interaction on their behavior is unknown. However, their populations are decreasing due to commercial or artisanal fisheries in many countries and the species is near threatened.

Those brain parts that are especially enlarged in manta rays imply strong sensory and learning abilities, also a well developed and complex social life. Based on the neurobiological results I designed a specific experiment on the role of different sensory cues on food searching behavior of a captive giant manta ray in the Lisbon Aquarium in 2004. Interestingly, the animal relied on visual cues rather than olfaction while foraging, even though manta rays usually live in plankton rich water with poor visibility. To imply this interesting finding on wild specimens I started preliminary observations and an experiment on the visual abilities and social behavior of manta rays in the Maldives and in Ecuador in 2009 and 2010.

The previous neurobiological research and the preliminary experiments on wild individuals suggest that manta rays might have cognitive abilities only known from other large-brained animals, such as elephants or dolphins. The experienced curiosity and interest of these animals toward humans, as well as the results of the preliminary studies have inspired me to conduct more detailed experiments in a well-controlled environment.

I have been in contact with the Atlantis Aquarium at the Bahamas for many years in order to continue the behavioral experiments on the sensory, learning and cognitive abilities of manta rays. My hope is that the results of this research will be useful for designing conservation and management plans for manta rays and for increasing public awareness through education about these fascinating animals.

Now it is time to start! Counting the hours back!