Shell trade pushes giant clams to the brink

By Christina Larson, in Tanmen, China At the Xiaobao Craft Store in Tanmen on Hainan Island, in southern China, co-owner Mo Xiaobao gestures to glass cabinets filled with white and yellow bead necklaces, translucent bracelets, and pendants strung with dragons or Buddhas. “All this is carved from giant clams,” he says, proudly. Behind him, wooden shelves hold ornate statues up to a meter tall: leaping fish, eagles with spread wings, grapevines intertwined with fruit. Prices approach $3000. Mo is eager to make a sale, but don’t try to leave China with one of these curios, he warns: “You might have trouble with foreign customs.” As countries crack down on the trade of elephant tusks, constricting illegal ivory exports to China, shells of giant clams—the “jade of the sea”—have become the new rage in scrimshaw. In China, “there’s huge demand, which has pushed up giant clam prices,” says Zhang Hongzhou, an expert on the trade at Nanyang Technological University in Singapore. And that is taking a heavy toll on the mollusks, which can span a meter and play a key role in reef ecosystems. The main giant clam species targeted— Tridacna gigas—is considered vulnerable to extinction based on survey data from 20 years ago. Its status has since eroded considerably, says Mei Lin Neo, a marine biolo

gist at the National University of Singapore. “There is a wide-scale consensus among numerous nations that clam numbers have declined over the past 10 years,” she says. For centuries, Hainan fishers harvested giant clams for meat, which is considered an aphrodisiac in China and a delicacy in France, Japan, and elsewhere. Found throughout the tropical Indo-Pacific, the mollusks thrive in the South China Sea, which is an “especially important” part of their habitat, Neo says. Trade in the shells— translucent white, sometimes streaked with yellow or red, and weighing up to 200 kilog rams—began about 20 years ago, Zhang says, when a Taiwanese entrepreneur showed locals how to carve intricate designs. But only in the past few years has the handicraft industry taken off. Fueling the boom, Zhang says, are improved carving techniques, Hainan’s popularity with tourists, the growth in e-commerce and the domestic wholesale market, and rising demand as ivory sources dry up. Tanmen, once a sleepy fishing vil

lage, is the epicenter of the trade: According to Zhang, it now has at least 460 shops and 100 workshops, and the industry supports nearly 100,000 people on Hainan. Prices paid to fishers for large raw giant clam shells have leaped 40-fold in 5 years, from a few thousand yuan a few years ago to 80,000 yuan ($12,100) today, he says. A Hainan government report states that especially fine and large carvings can fetch up to 700,000 yuan ($106,000). To feed the booming industry, Chinese fishers are pillaging the South China Sea for the creatures. That’s adding to the tension in the region, which is already a geopolitical flashpoint because of China’s expansive territorial claims. As stocks dwindle, Chinese fishers are ranging more widely into disputed waters. Ed Gomez, a marine biologist at the University of the Philippines, Manila, says he has examined recent footage taken by divers showing Chinese fishers operating at Scarborough Shoal—claimed by China, Taiwan, and the Philippines—“digging

Date Published: September 9, 2019

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