In April 2021, the Philippine authorities made a remarkable discovery. In a beachfront property on Sitio Green Island in Palawan Province, they found giant clam shells one after another on the beach. These are protected species. The stock of artillery shells weighed more than 200 metric tons, and its commercial value was estimated to be approximately 1.2 billion Philippine pesos (US$23.6 million), which was the largest confiscation in Palawan.

This seizure was not an isolated incident. In the past five years, the authorities have reported 13 seizures of similar clam shells across the Philippines. Federal law prohibits the collection, possession or trading of 7 of the 12 known giant clams. Violators will face fines or imprisonment.

The frequency of these seizures led investigators to work with the Dutch-based NGO Wildlife Justice Commission (WJC) to identify the huge clamshell trade as a “cause of concern”. A new report issued by the organization on October 6 indicates that the transaction is likely to be linked to an organized criminal group. According to the report, because carvers may use huge clam shells as a substitute for ivory, this may also endanger elephants. It also pointed out that China and Japan are potential markets to watch, although it pointed out that little is known about trade in these countries.

WJC executive director Olivia Swaak-Goldman told Mongabay in a telephone interview: "We think this is an important issue that needs to be pointed out." "Giant clams are not as attractive as other iconic species... and they are often overlooked. However, they are The impact of illegal trade can be very large."

The legendary "cannibal", giant clam is the largest shellfish in the world. The largest of these giants, Tridacna gigas, can grow to about 1.2 meters (4 feet) wide and weigh about 226 kg (500 pounds), which is about half the weight of a grand piano. Giant clams mainly exist in the shallow coral reef systems of the Pacific, Indian Ocean, South China Sea and Red Sea. The coral triangle of the South Pacific has the highest species diversity.

For centuries, people living in coastal communities in Asia and the South Pacific have harvested giant clams for meat. But the WJC report stated that there has been a significant increase in the illegal poaching of clams for luxury food, aquarium trade, and ornamental carvings in the past 50 years.

The report focuses on the latter industry, which became highly commercialized in the 1990s. In Hainan, the southernmost tropical island in China, artisans set up shops, turning huge clam shells into bowls, beads, and gorgeous exhibits. According to reports, between 2013 and 2014, there were about 150 processing workshops in Hainan, providing services for 900 craft shops.

Neo Mei Lin, a senior researcher at the Singapore Institute of Tropical Marine Science, visited Hainan in 2016 to investigate the trade. She told Mongabay in an interview with Zoom that when she peeked from the doors of various warehouses, she saw a "very large" stock of clams, which looked like they could be stored for several years. "You can imagine an entire house filled with these shells," she said.

According to the WJC report, in order to meet the needs of this carving industry, fishermen dig mud or drill on the seabed, and even use boat propellers or anchors to break down coral reefs and release clams, and dig out clams from the reef. In 2016, satellite data showed that 104 square kilometers (40 square miles) of the South China Sea-a global biodiversity hotspot-was destroyed by these mining methods.

"The process of obtaining materials must be very, very destructive to the environment," Neo said. She added that not only would this extraction damage the seabed, but removing giant clams would also endanger countless marine species that depend on giant clams for food and shelter.

Neo says that the most commercially valuable giant clam shells are “fossilized” after being in the seabed for a long time because they provide a thicker surface for carving. She said that when huge clam shells display rich red, purple, and brown tones, or translucent emerald-like tones, their value is also higher.

WJC reports indicate that the translucent giant clam shell resembles ivory when carved. Therefore, investigators speculate that when China enacted a ban on ivory in 2018, clamshells may be increasingly used as a substitute for ivory.

In 2017, Hainan Province banned the trade of giant clamshells. Despite this, a report showed that Hainan's flip-top suppliers were still selling their products in early 2019.

A giant clam shell carving from Hainan, China. Image courtesy of Mei Lin Neo.

Concerns about the sustainability of the giant clam shell trade have led officials to list giant clam species in CITES Appendix II, the Global Wildlife Trade Convention, which strictly regulates their trade. However, it is not clear whether these protection measures have a major impact on the protection of giant clams.

Currently, the only indicator of the size and severity of transactions is the number of seizures reported. Since 2016, the Philippines has seized 14 giant clam shells, the largest of which occurred in October 2019, when officials confiscated 120,000 metric tons of shells, estimated to be worth US$39 million. According to the WJC report, China also reported 46 seizures, but most of them involved "a small amount of retail-grade shells and shell crafts", and only one was related to the Philippines.

Despite the scarcity of information, WJC stated that large clamshell traders may be involved in organized crime. This assumption stems from the complex logistics, organizational, and financial evidence required to collect and transport large numbers of giant clamshells. Swaak-Goldman said that after seizures, arrests and prosecutions are often avoided, which shows that "considerable impunity" is happening.

The report also pointed out that 17% of clam shell seizures also contained ivory, as well as other types of ivory such as mammoths and narwhals, indicating that criminal groups that traffic in ivory may also be clam shells. Other giant clam shells seized contained other illegal seafood such as hawksbill turtle shell crafts, corals and seahorses.

"These are things that require more research," Swaak-Goldman said. "But these are the reasons why we think it is very important to be alerted to this issue."

The report also shows that Japan is a market worth watching because its government currently does not provide any protection for giant clams. In addition, Japan has a legal market for giant clam shells and ivory. But at present, investigators have not found any smuggling routes from the Philippines to Japan or China.

Swaak-Goldman stated that the lack of information about giant flip deals prompted WJC to publish its report.

"What we need to do is start filling in these intelligence gaps," she said. "And come up with more knowledge about smuggling routes, how they operate, and key drivers. The way to do this is through intelligence-led investigations."

Kanitha Krishnasamy, Southeast Asia director of TRAFFIC, a non-governmental organization that oversees the wildlife trade, agrees that lack of information is a problem, especially because there is evidence that clamshell seizures in the Philippines are on the rise.

Krishna Sami told Mongabay in an email: "If the intelligence and information gap is bridged, the government will be able to better respond to this problem and take stronger control measures."

"As with the trade of many species, proper regulation of legal trade and combating illegal activities are crucial," she said. "Both of these will benefit greatly from more detailed investigations and reviews, especially when the WJC report points to the convergence with other commodities."

Feltham, J., & Capdepon, L. (2021). Giant clamshells, ivory, and organized crime: analysis of potential new relationships. Retrieved from the Wildlife Justice Commission website: https://wildlifejustice.org/wp-content/uploads/2021/10/Giant-Clam-Shells-Ivory-And-Organised-Crime_A-Potential-New-Nexus_WJC_spreads.pdf

Banner picture caption: A warehouse in Hainan filled with beads carved from giant clam shells. Image courtesy of Mei Lin Neo.

Correction (10/18/2021): Modified the information source of the clamshell stores that are still open in Hainan in 2019.

Elizabeth Claire Alberts is a staff writer for Mongabay. Follow her on Twitter @ECAlberts.

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