The scales arrived in bulging, stained bags. Hundreds of them.

They sailed into a Singapore inspection port by shipping container, the vessel marked “frozen beef” and bound for Vietnam. Inside, customs officials found the sacks, packed and piled from floor to ceiling. They overflowed with the product of a wildlife smuggling operation so vast, yet so niche, it had conservationists worried about the extinction of an animal that most people haven’t even heard of yet.

The scales — 14 tons of them — belonged to roughly 36,000 poached pangolins. It is the largest-ever seizure of its kind, another grim superlative for the scaly anteater, which is believed to be the most-trafficked mammal in the world.

“We’re hearing the last death knell of pangolins,” said Crawford Allan, the senior director of TRAFFIC, a World Wildlife Fun partner that monitors illegal wildlife trade. “This is our last chance to save them. They cannot sustain this level of poaching and trafficking.”

The diverted haul, which originated in Nigeria, would have been worth almost $39 million, officials said in a statement last week.

The case of the pangolin, native to parts of Africa and Asia, illustrates the difficulty of cracking down on the illicit global trade of exotic wildlife. The conservation cause suffers from a lack of public awareness; yet, the more people know about pangolins, the more popular they become. And when animals become popular, business booms for poachers and smugglers.

Over the last decade, a sophisticated criminal network has developed methods of marketing trafficked animals to consumers around the world, Allan said, convincing wealthy people that elephant tusks and rhinoceros horns are the latest status symbol or medicinal panacea.

But pangolins, he said, are even more vulnerable than their forebears. In China and Vietnam, where most buyers live, several segments of the black market consider them desirable.

Restaurants buy pangolin meat, which is considered a delicacy, an off-menu item that a well-heeled customer might order when trying to impress. Those seeking the new cure-all buy the scales, which are used in traditional medicine to treat everything from rheumatism to cancer, even though there is no known science that supports their remedial properties. And the fashion industry has shown interest in the skin, its diamond pattern making for an attractive leather design. It’s scale-to-tail consumption.

“The poor pangolins have a giant target on their backs,” said Paul Thomson, the vice chair of the Pangolin Specialist Group and the co-founder of Save Pangolins. “To me, it’s a crisis.”

The International Union for Conservation of Nature now considers all eight pangolin species to be threatened with extinction. Two of those species are critically endangered. A pangolin disappearance would have reverberations throughout their habitats, Thomson said.

“They’re so evolutionary distinct that losing pangolins would mean we lose a key part of our biodiversity,” he said.

They resemble real-life Pokémon, covered in scales that resemble artichoke leaves. They have a penchant for burrowing, tunneling underground in search of the ants and termites on which they survive. When in danger, they curl into a ball, an evolutionary trait that has made them even more susceptible to poaching, because a person can simply pick them up off the ground. They can weigh as little as 3½ pounds and as much as 75. They’re nocturnal, solitary and difficult for scientists to study. And experts don’t even know how many remain.

“When I see 36,000 vacuumed out of West and Central Africa, I really wonder: How many can there be left?” Thomson said.

The nascent community of pangolin conservationists is in the process of answering that question, trying to conduct a transcontinental survey to determine how many are still in the wild.

But in the meantime, high-profile seizures like the one in Singapore — and two others in Malaysia and Hong Kong in February — should serve as a wake-up call for international regulatory agencies, Allan said. Next month’s Convention on International Trade in Endangered Species could provide a key opportunity for countries to coordinate a global response, he said. It was at CITES 2016 that pangolin trading was first formally banned.

Since then, international law enforcement has done a better job spotting smuggled pangolins or pangolin scales, Allan said, but agents rarely catch traffickers in the act. More often they end up with a shipping container full of contraband and no suspects.

Authorities may have more success working with social media sites and online marketplaces — Facebook, Instagram and Alibaba among them — to tamp down on online sales, Allan said. And advocates, Thomson added, can do their part by educating the public. A recent shout-out from Hillary Clinton and John Kasich probably won’t hurt, either.

“You can’t save a species,” Thomson said, “if nobody knows they exist.”

Correction: An earlier version of this article misspelled Crawford Allan’s last name.

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