Mexican “Tequila” Fish Extinct in Wild Successfully Reintroduced Maria Verza - Associated Press
go to original January 6, 2022

Conservationists from Michoacana University of Mexico return the tequila fish to the wild

There once was a small fish called “tequila splitfin” or “zoogoneticus tequila” that swam in a river in western Mexico, but 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 with the community’s identity and being touted 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 vanished from local waters, apparently due to pollution, human activities 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.

In 1998, conservationists from the Chester Zoo in England and other European institutions arrived to help set up a laboratory for conserving 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 told us it was impossible, (that) when we returned them they were going to die.”

So they looked for options. They built an artificial pond for a semi-captivity stage and in 2012 they put 40 pairs there.



The tequila fish, which grows no longer than 70 millimetres, disappeared completely from the wild in 2003 (The Chester Zoo)

Two years later, there were some 10,000 fish. The result guaranteed funding, not only from the Chester Zoo but also a dozen organizations from Europe, the United States and the United Arab Emirates, to move the experiment to the river.

There they studied parasites, microorganisms in the water, the interaction with predators, competition with other fish, and then introduced the fish in floating cages.

The goal was to re-establish the fragile equilibrium. For that part, the key was not so much the scientists as 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.

Read the rest at WPRI

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