Underneath the muddy waters of Lake Pátzcuaro in Michoacán, Mexico, a small number of slippery salamanders make their home. With gills like a lion’s mane, the achoque salamander holds years of wonder. For centuries, Indigenous Purépecha communities valued achoques as food and medicine, and some of the salamander’s closest cousins were even worshipped as water gods. Scientists have found that these cryptic achoques have amazing abilities: They can regrow limbs, brains and even their hearts.
Even with unparalleled ability to regenerate, achoques — or Ambystoma dumerilii — are listed as critically endangered by the International Union for Conservation of Nature. It is estimated that less than 150 achoques are left in the wild, all of them in Lake Pátzcuaro. The salamanders are sensitive to pollution due to their permeable skin, which can quickly absorb toxins. Along with pollutants in the lake, the arrival of non-native species such as carp and bass, which eat achoques and their eggs, led to the historic decline.
Recently, Mexican conservationists, Dominican nuns, and scientists from the U.K.-based nonprofit Chester Zoo teamed up to save the achoque salamander. The team discovered a way to use microchips to identify individual achoques in captivity and, eventually, in the wild. Microchips allow scientists to monitor the health of individual salamanders, assess the average age of a species, and better understand how many remain in the wild.
A tried-and-tested technology, microchips are frequently used to identify animals, from pet dogs to wild tigers. But salamanders are notoriously difficult to tag.
“Some species of salamander, if you microchip them, their body just rejects it,” said Adam Bland, a scientist at Chester Zoo who led the effort. “These salamanders are also extra weird because of the way they can regenerate limbs, so we weren’t sure if microchipping them would actually work as a permanent way of marking them.”
Under veterinary advice, the team of scientists at Chester Zoo and the Michoacán University of San Nicolás de Hidalgo discovered that installing the chip in the folds of the achoques’ skin held it in place thanks to gravity. In under a minute, the team carefully inserts the microchip with a needle using a special, wet cloth to hold the achoques still, which can also be difficult. “They’re like a bar of soap,” Bland said. “They’re so slippery.”
The researchers were the first ever to microchip 80 achoque salamanders from different captive colonies. After several months of monitoring, the scientists reported a 97.5 percent success rate in salamanders retaining the microchip without any negative health effects.
The team had an unexpected assist from Dominican nuns at the Monasterio de la Virgen Inmaculada de la Salud in Michoacán, who have raised achoques for years. When the salamanders began to disappear from Lake Pátzcuaro near their convent, the sisters started breeding achoques for their medicinal value. They sell traditional cough syrup made from achoques, which they claim helps with respiratory illnesses such as asthma, breathing problems and cough.
“God thought about creating the achoque with love,” sister Maria del Carmen Perez, who has been taking care of achoques since joining the monastery, told PBS. “I think the achoque’s mission is to give health and survive.”
The monastery now has the largest collection of achoques in the world, some of which were a part of the microchipping effort.
While tagging populations is a standard practice in conservation, scientists often disagree about whether “ex-situ” conservation, or protecting an endangered species outside its natural habitat, is the best method to ensure the survival of the species. For example, researchers found wild achoques to be bigger and slimmer with larger tails compared to captive populations, which helps them swim better to catch food and escape predation.
At Michoacán University of San Nicolás de Hidalgo, aquatic biologist Omar Dominguez-Dominguez is leading efforts to ensure the survival of the achoques in Lake Pátzcuaro, their original home. The research project is now focusing on tagging wild achoques to monitor their health and assess how many survive in the lake. Scientists capture achoques from the lake, tag them with microchips and release them back into the wild. The tagging allows scientists to more accurately model the population by monitoring them and estimate if conservation efforts are successful.
Researchers are also involving fishermen from the Indigenous Purépecha community of San Jerónimo Purenchécuaro, where the livelihoods and worldview of the community are closely tied to the lake. When fishermen cast their nets, salamander eggs can get caught and usually die. Dominguez and other scientists are working with fishermen and members of the community to collect achoque eggs, grow the salamanders in aquariums, and release them back into the wild to restock the population. “The team works really closely with local communities,” Dominguez said.
The project also focuses on educating people who live around Lake Pátzcuaro about achoques. Dominguez believes the cultural and economic value of achoques as food and medicine helps conservation efforts. Spreading awarness is revolutionizing how local people perceive the importance of salamanders, Dominguez said. “[This project] has opened the door for the conservation of the salamander.”
