By Rebecca Pilkington-Vincett A feeding station popular with manta rays is not far from the Misool Eco Resort and Conservation Center in Raja Ampat, eastern Indonesia.

RAJA AMPAT, Indonesia —They’ve been described by one scientist as “pandas of the ocean.”

“They’re such an iconic species, beloved by divers,” said Andrea Marshall, director of the Marine Megafauna Foundation, who came up with the description during an interview with NBC News. “They’re just amazing.”

Unlikely as it might seem, the panda and the manta ray have a lot in common.

Just as scientists still haven’t been able to confirm the number of pandas in the wild, they also have no idea how many manta rays exist.

“Globally we don’t know how many manta rays there are,” said Guy Stevens, director of the U.K.-based Manta Trust, whose research is largely based around manta populations in the Maldives.

But -- again, like the panda -- scientists think it’s a small population.

“If they’re lucky, (manta rays) have two pups (over several years). That’s a very low reproductive rate, especially compared to your average fish,” said Dr. Heidi Dewar, a biologist at the Southwest Fisheries Science Center, part of NOAA.

Anecdotal evidence suggests mantas are under threat, and China may be a major reason for it.

Manta rays are vulnerable on two fronts: as bycatch — getting caught in industrial fishing nets targeting different types of tuna — and, increasingly, because of traditional Chinese medicine, or TCM.

Manta rays are abundant in the waters around Raja Ampat, eastern Indonesia.

Manta rays are harvested for their gill rakers, which allow the fish to filter food from water. Some Chinese believe they have healing properties or are good at cleaning out toxins. One Chinese-language website claims gill rakers enhance the immune system, promote blood circulation and aid in the treatment of cancer, skin disease and infertility.

“It’s just cartilage,” said Dewar, echoing skepticism expressed by many scientists.

Medicinal fad?

Conservationists say manta rays aren’t even considered “traditional” medicine and argue no reference to the animal can be found in TCM books dating back a century. But with rising incomes that enable Chinese consumers to readily adopt medicinal fads, the impact on manta rays has accelerated over the past 10 to 15 years.

“A lot of it is completely unrecorded,” said Stevens, who worked on a project founded by Shark Savers and WildAid to document the scope of gill-raker harvesting.

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Researchers looked at the location, value and species involved. “It does seem the majority of all of those gills that are being traded are ending up in China,” Stevens said.

The conclusion, published in a report called Manta Ray of Hope, found that roughly 3,400 manta rays and 94,000 mobulas (related to the manta ray family) are caught each year, but the numbers reflect only reported catches. “Unreported and subsistence fisheries will mean true landings are much higher,” the report said.

On patrol with a shark ranger in Indonesia's marine treasure trove

Visits to random TCM shops in Beijing and Shanghai turned up no gill rakers. In fact, a veteran pharmacist at Tongrentang, a long-established purveyor of traditional Chinese and herbal medicines, said she had never heard of manta rays being used this way.

But the Manta Ray of Hope report estimates a mature ocean manta could yield up to 15 pounds of dried gills that can bring in as much as $230 a pound in a market in China.

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Marshall said she has noticed an uptick in manta fishing. “I’ve been (in Mozambique) in the last decade … and we’ve seen an 87 percent decline in the population because of the fishing.”

Unlike many shippers, Chinese merchants who transport cheap products from the mainland for export to Africa “want to fill [their unloaded cargo vessels] with resources wherever they go. In Africa, they fill it up with wood, fish or shark’s fin,” she said. “They’ll go out to the local fisheries along the coastline and scout for these products.”

The scientist has spoken to members of local communities, who say the Chinese offer “new nets, new lines, new hooks. (The Chinese traders) say to them, ‘If you get the sharks or the mantas or the turtles, you get all the meat. You can keep all the meat. You just sell us the things you don’t normally eat.'”

Protecting a ‘threatened’ species

Mantas were listed last year as “threatened” under the international Convention on the Conservation of Migratory Species.

The International Union for the Conservation of Nature has classified the manta ray as “vulnerable” to extinction.

PhotoBlog: Raja Ampat archipelago: The world's last paradise

Chinese scientists have also weighed in.

“In the last two years, we have conducted evaluations of the manta ray and submitted a recommendation to the government to list it as a protected species,” said Professor Wang Yanmin from Shandong University’s Marine College.

“There is no regulation for protecting the manta ray so sales of mantas are not illegal,” said Feng Yongfeng, founder of Green Beagle, a group that promotes environmental protection.

Groups like Manta Trust are focusing on getting manta rays listed by the Convention on International Trade in Endangered Species (CITES). But scientists have their work cut out for them.

“It’s very difficult to get listed on CITES. They ask for a lot of detail that is difficult to pin down,” said Marshall. “Maybe in the terrestrial world, biologists can provide those kinds of details. When you’re talking about the megafauna [or large marine species] world, it’s very difficult.”

Marshall – who discovered a second type of manta ray in 2008 and is in the process of identifying a third -- acknowledges little is known about them.

AFP - Getty Images file A huge manta ray weighing more than 2,200 pounds and measuring nearly 9 yards in length was caught off the eastern coast of China this past September.

Manta births a mystery

Vexing questions include the manta’s life span, details of their reproductive ecology and migratory patterns.

“I could wrap my life up in 20 minutes if I could talk to them,” she joked. “It has been driving me insane for the last ten years because I haven’t been able to figure out where they give birth. It’s 2012 and nobody has ever seen a manta give birth in the wild.”

And research is painstaking. For one, concentrations of the animal tend to be around far-flung islands. Stevens of Manta Trust cited the costs of tracking mantas and the difficulty in locating and knowing how to study them.

With technological improvements, however, scientists are gaining some ground. Satellite tags are one way to help the research. “What do they do when we can’t observe them? I’d love to follow an animal to find out how they spend their time,” said Stevens. “The tagging gives you small glimpses of them.”

Two dive instructors at the Misool Eco Resort and Conservation Center in Raja Ampat have uncovered a revenue stream to offset research costs: tourism.

“One manta ray can raise $1 million (U.S. dollars) in tourism income over its lifetime,” said Rebecca Pilkington-Vincett, citing a figure contained in the Manta Ray of Hope report.

PhotoBlog: Raja Ampat archipelago: The world's last paradise

With the blessing of the resort, Pilkington-Vincett and Calvin Beale launched a research project off the surrounding reefs.

Last season, the duo raised $32,000 from donations by recreational divers who accompanied them on dives to gather DNA samples and tag the mantas.

With the money, they have bought three satellite tags and collected numerous DNA samples. They are sending off the data to the Scripps Institution of Oceanography for analysis by a graduate student.

With online databases such as the Manta Research Project, where some of Pilkington-Vincett and Beale’s data are logged, or the Manta Matcher, developed by Marshall and operating much “like the FBI fingerprint online database,” research on the manta ray has become rooted in a global exchange among scientists and amateurs alike.

Until its secrets are fully revealed, the manta’s mystique seems guaranteed.

“I think it’s fascinating,” said Dewar of the Southwest Fisheries Science Center, “that there is such a large and amazing creature that has so many mysteries attached to it.”

Additional research by Le Li, Johanna Armstrong and Yanzhou Liu.

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