At first glance there’s nothing remarkable about Mexico’s tequila splitfin fish. Only two and a half inches long, the fish aren’t colorful or poisonous. They aren’t particularly fast. They don’t change colors or exhibit other strange behaviors. They are often forgettable. The fish was endemic to a single spring-fed stream in the Mexican state Jalisco. In 2003, the fish went extinct. There was no international outcry, and even a newspaper article to say goodbye to the fish.
But scientists at Michoacán University’s Aquatic Biology Unit knew the tequila fish, as it is commonly called, played an important role in the river’s delicate ecosystem—eating dengue-spreading mosquitoes and serving as a food source for larger fish and birds. A team of international scientists joined forces to save the fish in the 1990s when it became apparent that the fish were disappearing. After the fish went extinct in 2003, the team would attempt something that had never been done before in Mexico—reintroduce an extinct species back into its native habitat. Now, almost two decades on, a thriving population of tequila fish, some 2,000 strong, once again call the Teuchitlán River home, swimming in the crystalline waters in the shadow of the tree-covered hillside.
The ambitious Conservation translocation project began in 1998 when English aquarist Ivan Dibble arrived at Michoacán University with some very precious cargo—five pairs of tequila fish from England’s Chester Zoo. Scientists at the zoo believe that the reason the tequila fish became extinct in the wild was a combination of pollution and the introduction of invasive species. Scientists could create a controlled environment for the fish in captivity.
For 15 years, biologists at Michoacán University cared for the tequila fish. “At the beginning, all these people said we were crazy,” says biologist Omar Domínguez, who worked on the project. Although reintroduction programs have been successful elsewhere, this was the first attempt by scientists to do so in Mexico. If the project failed, Dominguez worried, “all the people [would] say, ‘okay, it’s impossible to reintroduce fish.’”
Dibble’s colony of 10 fish grew. The team transferred 40 pairs tequila fish from Dibble’s colony to an artificial pond at the University in 2012. They had to show that the fish could survive in a seminatural environment. The fish had competed for food, dealt with parasites, avoided predators such as birds, turtles and snakes in the pond. It was the same environment as the wild. The school of 80 grew to approximately 10,000 in four years. Researchers were able to raise enough money to finish the project: restoring the tequilafish to the wild.
Domínguez knew that the only way to do that successfully was to get the local community in the town of Teuchitlán involved. The river could be again destroyed if it is not cleaned and protected by the community. Federico Hernández Valencia, professor of environmental education at Michoacán University, was called in. He quickly joined local volunteers Pilar Navarro and Martha Hernandez, who helped to create the community initiative. Guardians of the RiverIn 2021.
As Valencia and local volunteers painted murals of the fish around town, local children chose a nickname for the tequila fish, landing eventually on “Zoogy,” after the fish’s scientific name, zoogoneticus, tequila. (In the 20th Century, many locals called the fish gallito or “little rooster,” because of the strip of bright orange that decorates male fishes’ tails. Others called the fish “little rooster” or “little rooster”. burrito or “little donkey,” says the Guardians’ Perla Espinoza, though she is at a loss to explain why.)
Domínguez and Valencia also led workshops about the local ecosystem and zoogy’s place in it. Students were taught how to recognize the tequilafish by looking at enlarged photographs of the males and female fish. The local Catholic church also supported the effort by providing classroom space, hosting fundraisers and helping to inform the community about how important the tequilafish are.
Domínguez and Valencia also led workshops about the local ecosystem and zoogy’s place in it. Students were taught how to recognize the tequilafish by looking at blown-up photos. The local Catholic church also supported the effort by providing classroom space, hosting fundraisers, as well as helping to inform the community about how important the tequilafish are.
Finally, 1,500 tequila salmon were reintroduced into the river in 2017 in floating cages. They quickly multiplied. After several months, biologists marked them and released them from their protective cages. Now a stable population of around 2,000 fish are again happily swimming in the Teuchitlán River, It is located approximately 40 miles west Guadalajara. The fish even moved to another part of the river just last month.
Saving the tequila fish “is like a small light in the universe,” says Domínguez. Dominguez hopes that this success can be used to guide future reintroductions extinct fish species.
The Guardians of the River’s youth now attend weekly classes, conservation workshops, and river walks. Domínguez and the team have continued to work with the Guardians to reintroduce two other endemic species that went extinct from the river. In November 2021, the Guardians helped to release golden skiffia. skiffia francesaeReverse the flow.