Protecting the gentle manta rays at Hanifaru Bay
The Maldives are home to some of the most breathtaking marine life in the world, and one of the highlights for many visitors is the chance to swim with manta rays.
Reef manta rays (Mobula alfredi), are curious, gentle and acrobatic creatures that often approach divers and snorkelers in the water. It’s not uncommon to see them performing somersaults and backflips. Watching their graceful maneuverings, it’s easy to see why many cultures hold manta rays in high regard and consider them sacred animals.
But, it is essential to remember that these vulnerable animals are wild and should be respected. That’s why it’s important to follow the Maldives Manta Ray Project guidelines, which promote responsible diving and snorkelling practices.
The Manta Trust has created an evidenced-based code of conduct for swimming and diving with manta rays. Tour operators like dive guides can introduce this to their activities, offering a responsible approach to wildlife tourism that enhances the experience for the guests and causes less disturbance on the mantas. “It’s a win-win,” says Hannah Moloney, a Ph.D. student working in the Maldives and across Australia.
I met Hannah through her research work with Project Manta Australia, but she also cross-collaborates with the Maldives Manta Ray Project, which works to increase protection for manta rays and the ecosystems they call home through research, education and collaboration. They work with citizen scientists to collect data on manta rays and other marine life in the Maldives and promote conservation and responsible tourism.
Manta rays are the largest ray species, with some individuals growing up to 18 feet wide (5.5 meters) and weighing over 700 kilograms. They are unique and fascinating for so many reasons. They exhibit complex behaviours such as coordinated feeding to enhance feeding efficiency and avoid collisions. They are ovoviviparous, meaning that the eggs hatch within the mother's body and the young are born alive.
Hanifaru Bay is one of the best places in the world to see manta rays. They are typically found from May to November, with the season peaking between August to October around full and new moons. They are known to aggregate in this marine protected area because of the abundance of zooplankton that concentrates in the cul-de-sac.
Oceanographic influences brings a rich supply of nutrients and zooplankton to the site. The bay is so nutrient-rich, in fact, the water can look milky with particle matter. Mantas feed by swimming through the water with their mouths open, filtering zooplankton (copepods, arrow worms, salps and crustacean larvae like crabs) through their gills.
Mantas use their cephalic lobes (the flappy things near their mouths) like a funnel to increase the concentration of plankton. They also coordinate their feeding behaviours to “feed with friends” to make feeding more efficient. When the concentration of plankton is high, they may line up in a single file and use the slip steam of the manta in front. This is called chain feeding. If it’s very high, they can also cyclone feed, creating huge feeding chains, and swimming in a spiral, creating a vortex to pull the plankton into their open mouths. It is an extraordinary and rare phenomenon that is awe-inspiring to see.
The bay's coral reefs also provide a safe place for the manta rays to rest and breed.
Manta rays play a vital role in marine ecosystems by controlling the populations of smaller fish and plankton, which can have cascading effects on the entire ecosystem. Some manta rays have been known to migrate long distances, travelling thousands of miles between feeding and breeding grounds.
Swimming with manta rays in the Maldives is guaranteed to be an unforgettable experience. And by travelling with an ethical guide and following the guidelines set by the Maldivian Manta Ray Project and citizen science groups like the Maldives Whale Shark Research Programme, you will be helping protect these amazing animals and their marine habitat for generations to come.
Amanda Delaforce is a marine biologist and underwater photographer who has led dozens of ethical dive expeditions to the Maldives. More information, firstname.lastname@example.org; amandadelaforce.com. Photos courtesy of Amanda Delaforce Travel and Photography.
Protecting manta rays
Manta rays face several major threats, including:
Fishing: Manta rays are often targeted by fishing operations for their gill rakers, which are used in traditional Chinese medicine. This has led to significant declines in manta ray populations in some areas.
Bycatch: Manta rays are often caught as bycatch in fishing operations targeting other species. This can result in injury or death for the manta rays.
Habitat loss: Manta rays depend on specific habitats for feeding and breeding, and the destruction of these habitats can have a negative impact on their populations.
Climate change: Climate change affects ocean ecosystems in various ways, and manta rays will likely be affected. For example, rising ocean temperatures can cause coral bleaching and acidification, harming the plankton that manta rays feed on.
Pollution: In the oceans, such as plastic and chemicals, pollution can harm manta rays and their food sources.
Tourism: In some areas, over-tourism can harm manta rays and their habitats if not managed properly.
Lack of legal protections: Manta rays are listed as vulnerable by the International Union for Conservation of Nature (IUCN) and as endangered under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). But in some countries, they still lack legal protections.