The site for the camp is well chosen. Mangrove trees provide shade from the sun; from their hammocks, the two men can look out over the yellow sand of Chachacual Bay. Rocks rise at both ends of the beach, breakers crashing against them. Next to the camp, turtles have left their tracks in the sand. “They often come at night and keep us company,” says Mauro Habacuc Avendaño Luis, 81, known to everyone as Habacuc.
While Habacuc lights a campfire to make coffee, his son Rafael, 42, sets up a small tent for the night. Rain is forecast. “We’ve been camping in the same spot for many years,” says Habacuc. “From here, we roam the coast in search of the purpura snail.”
The two men, members of the Indigenous Mexican Mixtec people, aretintoreros, which means “dyers”. Their work on the Pacific coast is extraordinary: they are the last people to extract dye ink from a rare species of snail,Plicopurpura colummelaris, which belongs to the rock snail family. “It is one of the oldest methods still practised today for dyeing yarn for clothing,”says Mexican ethnologist Marta Turok. “The coastal Mixtecs in Oaxaca have been using it for at least 1,500 years.” The Mixtecs call the colourtixinda.
As the sun slowly sinks below the horizon, Habacuc and Rafael set out to search for the purpura snails and “milk” them – as they call the process of extracting the ink. Their work depends on the tides. “We can only reach the snails at low tide because they live in the zone where the surf hits the rocks,” says Habacuc.
The men climb from boulder to boulder, looking for the crevices where snails cling to the rocks, which are often covered in algae and extremely slippery. “One wrong step can cost you your life,” says Rafael. “We have lost relatives who have fallen and been swept away by the waves.”
They quickly find the first specimens about half a metre above the water level. Their shells are dark green to black, with small, knotty spirals and grooves on the surface. It takes strength and skill to detach them. “I have to pull the snail up decisively, tipping it sideways,” says Rafael. “If you hesitate, it clings even more tightly.”
After detaching a large female snail from the rock, he presses on its foot with his finger. The snail first excretes a small amount of urine, which he tips aside. Only then does it secrete a few drops of a milky substance, the actual ink. This contains neurotoxins, which the purpura snail uses to paralyse smaller snails and other marine invertebrates, which it then eats. The substance is harmless to humans.
Rafael lets the ink seep into a bundle of cotton thread wrapped around his left hand and puts the snail back in a protected place so that it can reattach itself to the rocks. After a few minutes, the snail secretion reacts with the oxygen in the air and the yarn turns yellow and, a little later, green. But it needs the sun’s UV light to achieve the brilliant violet colour which lies somewhere between lavender and amethyst.
“If the day is gloomy, the yarn stays green or blue,” says Habacuc. “You have to moisten it again and put it in the sun, then it turns purple, even if a year has passed since it was dyed.” It is said that the snail purple will never fade and cannot be washed out. “The clothes will disintegrate, but their colour will last for ever,” says Habacuc, pointing to his white shirt with its purple work stains. “If you rub purple-dyed yarn, it immediately smells of seaweed and the sea.”
Habacuc is the head Mixtec dyer in the small town of Pinotepa de Don Luis, the only place inMexicowhere the purpura tradition has survived. He learned how to milk snails from his uncle when he was 14. “I’ve been doing this for 67 years now, and you can see it in my feet.” He points to his toes, which are curled inward from clinging to the rocks. “Back then, we could walk from our village to the coast, 40km [25 miles] away, to milk snails.”
Plicopurpura columellariswas once native to the entire Pacific coast of Central America, from Baja California in the north to Colombia in the south. “We sometimes milked 3,000 snails in one day and dyed seven to eight large cotton strands with the ink,” Habacuc says. But that was a long time ago. The animals have long disappeared from the beaches of his youth. They are now found only in Huatulco national park, with its many inaccessible cliffs and wild coves. Even there, the tintoreros rarely find more than 100 snails a day. “The cost of travel and food is higher than my profit from selling the yarn,” says Habacuc. “The only reason we continue dyeing is the desire to preserve our traditions and culture.”
The decline of the snails began in the early 1980s, when Japanese companies discovered the ink and used it to dye fine kimonos. They hired fishers on the coast of Oaxaca to milk the snails – but they threw them into the water after milking them or left them lying in the sun. “They tried to milk the snails almost every day – and killed them,” says Habacuc. “The mollusc needs a lunar cycle to regenerate.”
The snail population declined dramatically within five years. The Mixtecs, with the support of ethnologists and biologists, raised the alarm. The Mexican government banned the Japanese companies and in 1994, declaredPurpura columellarisa protected species. Since then, only Mixtecs from Pinotepa de Don Luis have been allowed to milk them.
But new threats arrived, as the once remote coastal region experienced rapid development. Roads, hotels and restaurants were built. Thousands of tourists flock to the beaches and beautiful bays every year – and they demand seafood. “Again and again, we encounter poachers who seize every opportunity to make a few pesos. They don’t care about the extinction of a species,” says Habacuc. “The government talks about protection, but it doesn’t even monitor the beaches in Huatulco national park.”
Since anearthquake in 2020, the species’ future has been even more uncertain. During the tremor, the Pacific plate pushed a little further beneath the Mexican mainland, raising the coast near Huatulco by about half a metre. Some once-inaccessible rocky coastal stretches have since become within easy reach of poachers and tourists. Many coral beds were also elevated. Some are slowly dying, and with them millions of small species that are part of the purpura snail’s food chain.
The Mixtecs are the snail’s most important protectors. Their presence in the national park deters poachers, and they follow strict rules so as not to harm the purpura population. For example, not milking snails smaller than 3cm, banning milking during breeding season, and allowing the snails to regenerate for three to four weeks between milkings.
It is already dark when Habacuc and Rafael return to camp. They cook the beans they brought with them and warm tortillas around the campfire. “We always come for seven to eight days, dyeing during low tide and resting during high tide,” says Habacuc. “When our tortillas run out, we return home.” The dyed yarn is distributed among the town’s weavers. There are still about 60 women working as weavers in Pinotepa de Don Luis.
“The purpura snail and the purple tixinda dye are sacred to us,” says 79-year-old Socorro Paulina Lopez, Habacuc’s wife. She taught her daughter and two daughters-in-law how to weave. “We absolutely must preserve this tradition,” she says.
There are only 14 men left in Pinotepa de Don Luis who continue the dye-gathering tradition.
“We need more educational work so that the fishing communities understand how important the snail is to us and stop poaching,” says Habacuc. “We’re running out of time.”
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