The story of the not extinct fish

It is just a little fish, not very colorful, there is not much interest in terms of global conservation explains Gerardo García. Disappeared since 2003, he is back in the rivers of southwestern Mexico.

The species the Chester Zoo conservationist talks about, the Tequila fish, has now been returned to the wild after being declared extinct. The reintroduction is presented as an example of how freshwater ecosystems and species can be saved. Fundamentally, the local community, the people living near the Tequila fish release site in Jalisco, Mexico, are playing a key role in monitoring water quality. of rivers and lakes.

Professor Omar Domínguez, from the Michoacana University of Mexico, whose team took a leadership role in the reintroduction, said: “We could not have done this without the local people, they are the ones who do the long-term conservation. And this is the first time that an extinct species of fish has been successfully reintroduced in Mexico, so it is a true milestone for conservation.

While conservationists initially released 1,500 fish, they say the population is now expanding into the river system. It is a project, and a partnership, between conservationists in Mexico and the United Kingdom that goes back decades. It is a project that has now set an important precedent for the future conservation of many species of fish in the country that are threatened or even extinct in the wild, but that rarely come to our attention.

In 1998, at the beginning of the project, scientists from the Aquatic Biology Unit of the Michoacana University of Mexico received five pairs of fish from the Chester Zoo, delivered by the English aquarist Ivan Dibble. These 10 fish founded a new colony in the university laboratory, which the experts maintained and expanded for the next 15 years and that faces very similar threats.

In preparation for reintroduction, 40 males and 40 females from the colony were released into large artificial ponds at the university, essentially training captive-bred fish in a wild environment with fluctuating food resources, potential competitors, parasites, and predators. After four years, this population was estimated to have increased to 10,000 individuals and became the source for reintroduction to the wild.

It is hoped that it could be a model for other freshwater species, including the achoque, a close relative of the axolotl. that lives in a single lake in northern Mexico This unique amphibian, believed in local culture to have healing  has been saved from extinction, in part, by a local group of nuns, who run a captive breeding facility for the animals that animals can readjust to nature when they are reintroduced at the right time and in the right environments.