‘World’s most beautiful snails’ threatened by illegal trade

Their shells come in a wide variety of colors: pastel yellow and pink, brick red and black, pearly white and ochre. Regardless of hue, the markings of the six species of Cuban painted snails, as they’re known, accentuate the whorled shape of their grape-size shells, which swirl in upon themselves. You can get lost gazing at these marvels of nature, as if you’re peering down a whimsically colored staircase that spirals on forever.

Cuba is home to the world’s greatest diversity of snails, but no others have shells with such a range of colors and complex patterns. Painted snails, in the genus Polymita, have long been sought by collectors, who sell the shells to tourists or trade them abroad to the United States and Europe. This demand is one reason why Cuba lists all six species as critically endangered, and why it’s been illegal for more than a decade to take these snails from the wild. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which regulates global commerce in wildlife, has banned their trade since 2017.

Biologist Mario Gordillo holds a painted snail in Reyes-Tur's lab. Little is known about the snails, including how many may remain in the wild.

For the most part, the snails live in trees and shrubs, eating lichens and mosses, sources of the minerals that give their shells the stunning colors. Whether or not the colorations protect them from predators or provide some other advantage remains unknown, says Bernardo Reyes-Tur, a conservation biologist and snail expert at the University of Oriente, in Santiago de Cuba. The snails are ecologically important as a source of food for native and rare species such as the critically endangered Cuban kite. And, Reyes-Tur says, by devouring mosses and bark fungi, they also help keep trees healthy, including in coffee plantations.

One species, Polymita venusta, is so sedentary, Reyes-Tur says, that “some individuals stay in the same spot for six months.” The snails’ slow-moving ways and picky habitat needs make them vulnerable to disruption. Clearing of land by coffee growers and for other types of agriculture has greatly reduced their ranges, Reyes-Tur says. They’re also preyed on by native species such as sparrow hawks, as well as invasive animals, including rats.

The six painted snail species belong to the genus Polymita. This one is a Polymita picta—the largest, at more than an inch in diameter.

Warmer temperatures and more intense droughts associated with climate change pose another threat, potentially making conditions inhospitable for the vegetation the snails need to survive. A 2017 study in the journal Tentacle suggests that climate change alone could virtually eliminate habitat essential for two of the species by 2050.

Shell game

The Cuban public is becoming more aware of the harm caused by shell collecting and the other threats. Hernandez recalls a school trip to a coffee plantation when she was a teenager, three decades ago. Her group came across a mass of painted snails clinging to the trees. She marveled at them. “Then the boys began to kill them to get their shells. The girls killed them too, with sticks and hair clips. I started crying, and I went to tell the teachers.” Even the teachers didn’t object, because killing and collecting the snails was common, Hernandez says.

Between 2012 and 2016, Cuba’s customs department made 15 seizures totaling more than 23,000 painted snail shells bound for the U.S. According to Adrián González Guillén, a snail expert and photographer based in Cuba, the CITES ban hasn’t stopped the illegal trade, mainly to the U.S. and Spain and to various Asian countries.

González Guillén says customs officials are “very effective” at preventing tourists from taking small numbers of shells out of the country. But large shipments are still getting out. “The true serious illegal trade for the black market is linked to a well-organized team of people,” he says.

Reynaldo Estrada, a researcher with the Antonio Núñez Jiménez Foundation for Humankind and Nature, a non-governmental Cuban organization focusing on cultural and scientific issues, agrees. “There are indeed organized trafficking networks in Cuba,” he says.

Left: Bernardo Reyes-Tur takes measurements of Polymita picta shells in his laboratory. He hopes that by learning more about the rare painted snails, it will help in efforts to protect them.

Right: A woman in a town near Baracoa offers jewelry and thousands of painted snail shells for sale. Collecting the snails either for sale in Cuba or trading abroad is prohibited.

Cuba’s customs department and the Ministry of the Interior didn’t respond to numerous requests for comment about the illegal snail trade.

Painted snail shells are widely available on websites in the U.S, Spain, and Taiwan. Hundreds of their shells were available on eBay, but when National Geographic asked eBay spokesperson Ashley Settle about those listings, she responded that they violated the company’s rule not to sell wildlife products prohibited from trade under CITES. Within 48 hours, most listings had been taken down.

Collecting and selling painted snails in Cuba can lead to fines of up to about $20 per incident, according to Reyes-Tur. To see how how effective that deterrent is, D’Amicis browsed tourist shops near the town of Baracoa, not far from Alejandro de Humboldt National Park.

Vendors weren’t openly selling Polymita shells, he said, so he decided to play the naive tourist and ask around for something extra special to buy. Soon, a local couple invited him to their house and showed him five 25-gallon trash bags filled with painted snail shells. They had “easily, easily 30,000,” D’Amicis estimates.

Polymita sulphurosa, seen only in a few patches of forest, may be the most endangered of the six species. Forest clearing, climate change, illegal collecting—all these pressures make biologist Reyes-Tur worried about the long-term survival of Cuba's painted snails.

To protect Cuba’s painted snails, Reyes-Tur, Hernandez, and colleagues are working to educate Cubans and visitors about the animals’ rarity and vulnerability. They’re studying the snails’ biology, with a view to raising them in captivity and releasing them in the wild. They’re also partnering with farmers in eastern Cuba to encourage them to care for the animals on their land. In the future, Hernandez envisions that snail-watching tours could be arranged, providing an economic incentive for their conservation.

“They’ll see that it is more successful to protect them alive than to sell them dead,” she says.

For Hernandez, who’s devoted her life to saving painted snails, it’s an intense and consuming calling. “I have neither children nor husband... I just love my Polymitas,” she says. “I think that the most important thing is to continue this noble task of study, training of decision makers, environmental education with children and young people who are the future of society. We must put a lot of love to this task, and we can never tire.”