Mysteries surrounding these ocean giants are finally being solved, thanks to the unique research of 2013 National Geographic Emerging Explorer Andrea Marshall.
Andrea Marshall leads groundbreaking research and conservation programs to save globally threatened manta rays, other vulnerable marine megafauna, and their critical habitats. She founded the Marine Megafauna Foundation and has discovered two new species of manta ray.
A 3,000-pound underwater giant glides through the Indian Ocean toward Andrea Marshall, opens its vast 18-foot wingspan, brushes her gently with a fin, and the dance begins. A decade ago, Marshall, like the rest of the world, knew virtually nothing about manta rays. Then she fell in love with them, marveling that such a large, social, and widely distributed creature had been so overlooked by scientific study. With each graceful movement, the majestic species beckoned her to be a pioneer.
Year after year of "firsts" have followed. Marshall became the first person to ever complete a Ph.D. on manta rays. The first to gather such deep and carefully researched data on mantas, informing and validating greater conservation efforts. The first to discover a second manta species. The first to create a global database that can revolutionize the future of manta ray research.
The Marine Megafauna Foundation, which Marshall co-founded, conducts world-leading research from Mozambique's remote southern coastline, home to one of the largest identified manta ray populations. "I've now swum with thousands of mantas, but each time I see one, it still takes my breath away," says Marshall. "We make surprising new discoveries about their biology and behavior every day.
"They have the largest brain of any fish, make incredible ocean journeys, and dive almost one-and-a-half kilometers from the surface. They never sleep, but rather swim constantly over their 40-year lifespans. They're so curious and smart, always ready to interact and play with you. Mantas tangled in nets have sought me out and patiently allowed me to remove hooks and lines, even while trembling in pain. That level of trust is extraordinary."
Mantas are large and feed at the surface, so they often become entangled in fishing lines, get struck by boats, or are caught incidentally in nets. They are also killed for their lucrative gill rakers, which have emerged as a trendy medicinal tonic in China. Since manta rays produce only one pup every two to three years in the wild, human pressures now outstrip the species' ability to repopulate in areas where they are exploited unsustainably. Global manta ray numbers have been devastated; Marshall's own reef population in Mozambique has declined by over 88 percent in just a decade.
Marshall's groundbreaking research and global lobbying have been crucial in convincing governments and conservation organizations to legislate protection and create marine reserves. In 2013, her efforts helped make history-inclusion of manta rays in CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora), an agreement between governments that will help protect the iconic species.
Marshall makes multiple dives every day to observe behavior, attach satellite tags, collect genetic samples, and laser-measure and photograph the unique spot pattern on each manta ray she encounters. She possesses an uncanny ability to see and remember visual patterns, and recognizes most of the 950 different manta rays in her Mozambican databases by sight.
After observing certain individuals with prominent markings and a vestigial spine at the base of their tails, she became convinced a second species of manta existed. Marshall and her team proved the genus should be split into two visually distinct species-resulting in one of the largest new species discoveries in the last 50 years. She is now confident she has identified a third manta ray species in the Atlantic Ocean, a discovery she will publish in 2013.
Marshall's most lasting legacy may be a new automated online database for manta rays, giving researchers the unprecedented ability to share manta photos and findings globally. She also hopes to enlist the world diving community as citizen scientists who will contribute millions of photos and sightings records.
After earning her Ph.D., Marshall opted to stay at her field study site in Africa full-time rather than seek a university position. "To earn the trust of local government and communities, I had to immerse myself in the issues facing this coastline and make Mozambique my home. People here are poor, and exploiting resources has been the only way to feed their families. But they would rather earn a living from positive, non-destructive means."
By integrating locals into the process of conservation, creating alternative livelihoods, and promoting responsible ecotourism, Marshall hopes to create lasting change in the region. She is also active in research programs in Myanmar, Thailand, Ecuador, Brazil, and Indonesia. "There is such positive energy and momentum around the conservation of these species. We started small, but today we're building a global manta army."