By Annie Murray
With brains as well as beauty, the largest brains to body mass of any fish, manta rays have long been admired by scientists and divers alike but there is still so much we are yet to learn about them. Particularly, in the remote atoll of the Conflict Islands, Papua New Guinea. But that is now changing.
Over 200 kilometers from the mainland, these remote islands are a haven for wildlife, a key spot for manta rays, offering us the rare opportunity to research a much understudied and unknown population. Known to attract both species of manta rays, as well as their smaller cousins, the spine tail devil ray, the Conflict Islands is now a key research site for the Papua New Guinea Manta Project (PNGMP), a newly established affiliate project of the Manta Trust. This project hopes to delve a little deeper to answer some of the many questions about the manta rays of this remote region and thanks to the incredible donation from Sandrina Postorino, CICI board member and certified manta enthusiast, our new research project can ramp up our work.
Sandrina’s first up close and personal experience with reef manta rays, the prime species observed in the Conflict Islands, was back in 2015 and made quite an impact on her, one which sparked a love and fascination with these gentle giants. During a night dive in the Maldives, a unique and special experience, the mantas made their presence known, feeding on plankton attracted by the dive lights, dancing around her with their mouths so wide open you could count the individual gills.
In my experience, feeding events are one of the best times to watch manta rays. Moving between various feeding strategies, sometimes group, sometime solo depending on the conditions and how much plankton is sitting in the water, for me this is the time when their intelligence is most evident. These adaptations enable mantas to really push their feeding to it’s most efficient. This is one of the behaviors we have observe in the Conflict Islands – following the currents, in turn following the food, mantas spend their time in the channels indulging on the zooplankton sweeping through the atoll, highlighting the importance of this site for ongoing manta research.
Sandrina’s love for mantas has taken her to many corners of the planet. Back in 2018, she first travelled to Socorro Island in Mexico. Socorro is part of the Revillagigedo National Park, some 500 kilometers out to sea and only accessible after a 36-hour boat journey. It is also home to one of the largest aggregations of oceanic manta rays in the world. With a disc width up to 7m, these manta rays have a curious nature, one which makes encounters unforgettable for divers.
“When I saw the first one of that size, my heart almost stopped, and I thought I was dreaming when this majestic animal approached me very gently and looked right into my eyes.”
One of the unique features of Socorro is the behavior of these oceanics, attracted by the sensation of the dive bubbles on their bellies, they often approach to hover above a diver or right next them. As large as they are, they are also incredibly gentle and curious and actively interact with divers. As long as divers are careful to follow the Code of Conduct for manta interactions, giving mantas their space, allowing them to control the interaction and never touching them, these interactions can be magical as well as making little impact on the animals. This is a key aspect of the work being carried out by the PNGMP and the Manta Trust as a whole, insuring safe and sustainable interactions which minimise any disturbance to the mantas. If you want to learn more about how to interact with manta rays, please check out the Manta Trust website - How to Swim with Manta Rays (swimwithmantas.org)
“Their beauty and effortless movement through the water is mesmerising and one diver commented that watching them is like seeing angels for the first time.”
Sandrina returned to visit the Socorro manta rays earlier this year and took the opportunity to learn more about their life history alongside the threats which they are facing. As of 2020, oceanic manta rays are listed as ‘Threatened’ on the IUCN Red List due to a number of factors, many manmade. Their long gestation periods and low birth rates work against them, but the biggest threat to their survival is from becoming by-catch in nets, and targeted fisheries. Used in traditional Chinese medicine, vast numbers of rays are killed annually for their use in traditional Chinese medicine however, there is absolutely evidence to show any medicinal benefits. Like many, this angered Sandrina, leading her to want to do more.
“I was therefore delighted to hear about The Manta Trust and the organisation's dedication to manta conservation. When I heard that the Manta Trust is planning to conduct research in the Conflict Islands, I fully supported this initiative and decided to also donate funds to make this happen. We need to learn more about mantas in order to be able to protect them and ensure their survival. “
These threats highlight the need to learn as much as we can in order to conserve these highly intelligent and majestic animals and due to Sandrina’s generosity, the PNGMP are doing just that. I want to say a massive thank you to Sandrina. Your donation and support make a massive difference to our small but growing project. Papua New Guinea offers a special opportunity to study both species of manta rays away from fishing pressure, with its remote location giving us a unique insight into a much-understudied population, largely away from human pressure. With your donation we can dedicate more time and resources to learning more about the behavior and movements of the manta rays in the Conflict Islands, gaining a clearer picture of the size and dynamics of the population and how we can I turn ensure their conservation. I am excited to see where our research will take us and what secrets we can uncover about this population.
Thank you so much and best fishes Sandrina!
Dr Annie Murray
Papua New Guinea Manta Project Manager