A small fish once called “tequila splittingfin” or “zoogoneticus Tequila” lived in a river in western Mexico. It disappeared in the 1990s. Scientists and residents, however, have achieved the return of a species extinct in nature — but conserved in captivity — to its native habitat.
Its success is now intertwined in the community’s identity, and is being praised internationally.
It began more than two decades ago in Teuchitlán, a town near the Tequila volcano. A half-dozen students, among them Omar Domínguez, began to worry about the little fish that fit in the palm of a hand and had only ever been seen in the Teuchitlán river. It had disappeared from local waters, probably due to pollution, human activity, and the introduction of non native species.
Domínguez, now a 47-year-old researcher at the University of Michoacán, says that then only the elderly remembered the fish called “gallito” or “little rooster” because of its orange tail.
1998 saw the arrival of conservationists from the Chester Zoo in England, as well as other European institutions, to help establish a laboratory to preserve Mexican fish. They brought several pairs of tequila splitfin fish from the aquariums of collectors, Domínguez said.
The fish began reproducing in aquariums and within a few years Domínguez and his colleagues gambled on reintroducing them to the Teuchitlán river. “They said it was impossible and that they would die if we returned them.” They looked into other options. They created an artificial pond as a semi-captivity station and put 40 pairs of birds there in 2012.
Two years later, there were approximately 10,000 fish. The Chester Zoo, along with a dozen other organizations from Europe, America, and the United Arab Emirates, were able to fund the move to the river.
They studied the interactions with predators and competition with other fish. Then they introduced the fish to floating cages.
The goal was to restore the fragile equilibrium. The key to this part was not the scientists, but the local residents.
“When I started the environmental education program I thought they were going to turn a deaf ear to us … and at first that happened,” Domínguez said.
But the conservationists succeeded with patience and years of puppet shows, games and explanations about the ecological and health value of “zoogoneticus tequila” — the fish help control mosquitos that spread dengue.
Some residents created a nickname: “Zoogy” for the little fish. They made caricatures of the river and formed the “River Guardians,” which is a group that consists mostly of children. They collect trash, clean the river, and remove invasive plants.
Domínguez said it is difficult to say if water quality is better because there is no previous data to compare, but the entire ecosystem has improved. The river is cleaner, there is a smaller number of non-native species, and cattle are no more allowed to drink in certain areas.
The fish quickly multiplied in their floating cages. They were then marked so that they could be tracked and released. It was late 2017, and the population had increased by 55% in six months. The fish had moved to another section of the river last month.
Complex and time-consuming is the process of reintroducing extinct species back into nature. Przewalski’s horse is one example. The Arabian oryx and horse are another. The Chester Zoo reported Dec. 29 that the tequila splittingfin had joined that small group.
“The project has been cited as an International Union for the Conservation of Nature (IUCN) case study for successful global reintroductions – with recent scientific studies confirming the fish are thriving and already breeding in the river,” the zoo said in a statement.
“This is an important moment in the battle for species conservation,” said Gerardo García, the zoo’s curator of lower vertebrates and invertebrates.
The IUCN has listed the tequila splittingfin as endangered on its red list of threatened species. Mexico’s freshwater ecosystems are being threatened by pollution, over-extraction and other factors. According to a 2020 report by the IUCN and the ABQ BioPark, the United States, more than one-third (or 536) of the freshwater fish species in Mexico are at risk of extinction.
Still, in Mexico, Domínguez and his team are already beginning work on another fish that is considered extinct in the wild: the “skiffia francesae.” The Golden Skiffia could some day join “Zoogy” in the Teuchitlán river.
(This story is not edited by Devdiscourse staff.
