Seven Species of Giant Clam on Deck for Federal Protection

Giant clam in Paindane Reef, Inhambane, Mozambique
(Credit: Peter Southwood)

WASHINGTON (CN) – The National Marine Fisheries Service announced that seven of ten giant clam species petitioned for listing under the Endangered Species Act need further study. The 90-day review process found that the petition provided enough scientific evidence to move seven of the species to the second stage of the ESA listing process, known as the 12-month status review.

The petition was filed by “private citizen” Dwayne W. Meadows Ph.D., formerly the Coordinator for the NMFS’ Species of Concern Program, who is a conservation biologist and educator, with additional background in SCUBA diving and underwater photography.

Giant clams live along shallow shorelines and reefs in the tropical Indo-West Pacific region. The largest of the giant clam species, Tridacna gigas, grows up to 4.5 feet wide and can weigh up to 440 pounds. “The petition points out that the giant clam (T. gigas) is preferentially targeted for international trade due to its large size and because it is considered a desirable  luxury item in China thought to confer supernatural powers and improve health,” the action notes. “A pair of high quality shells (from one individual) can fetch up to US $150,000.”

A United Nations tribunal arbitrated a dispute between the Philippines and the People’s Republic of China last year regarding maritime rights in the South China Sea, including the matter of China’s poaching of giant clams.

“The Tribunal is particularly troubled by the evidence with respect to giant clams, tons of which were  harvested  by  Chinese  fishing  vessels  from  Scarborough  Shoal,  and  in  recent  years, elsewhere in the Spratly Islands. Giant clams (Tridacnidae)… play a significant role in the overall growth and maintenance of the reef structure…Excavation is highly destructive, with early reports showing a drop in coral cover by 95 percent from its original value. More recently, fishermen  in  the  South  China  Sea  are  reported  to  utilize  the  propellers  of  their  boats  to excavate shells from reef flats in the Spratly Islands on an industrial scale, leading to near-complete destruction of the affected reef areas,” the report stated.

The Tribunal found that China not only was aware of and tolerated the reef destruction, but actually aided and abetted the poaching. “China was aware of the harvesting of giant clams. It did not merely turn a blind eye to this practice. Rather, it provided armed government vessels to protect the fishing boats,” the report said.

According to the petition, the growing giant clam industry in China is the result of improved carving techniques, increased tourism in China, the growth in e-commerce, and the domestic Chinese wholesale market, but Meadows also cites a 2016 study that notes “concerns that stricter enforcement of the trade in ivory products has diverted attention to giant clam shells.”

The petition finding notes that there is evidence of significant population declines of all giant clam species range-wide and that threats are increasing, such as coral reef degradation from sedimentation, pollution and reclamation, subsistence and commercial harvest for meat, and for the aquarium and curio trades, inadequate regulation, and impacts from climate change, including coral bleaching and ocean acidification.

The agency found that the petition, coupled with the information the agency had in its files, justified moving seven of the petitioned giant clam species forward in the listing process, but fell short of making the case for three of the petitioned species. The agency now begins a 12-month review for each of the warranted species as they move toward listing under the ESA.

Neither Dr. Meadows nor the agency responded to requests for comments.

Information and comments must be submitted by Aug. 25.[/vc_column_text][/vc_column][/vc_row]

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