Researchers want to save Mexican “water monster” from extinction

O Mexico is home to the only animal in the world capable of regenerating itself: the axolotl . This 'water monster' or 'Peter Pan', as they call him, is a unique species that has caused fascination in Mexican culture and science. Today it is in danger of extinction and, to save it, scientists and farmers join forces.

“They call him water monster because it has a strange shape (…), different from what we normally see”, he told CNN Luis Zambrano, researcher at the UNAM Biology Institute.

This “aquatic monster” regenerates in such a way that “practically any organ” is cut, he explains, it grows back. “If a bird cuts off one of its limbs, it grows a limb again. If you lose an eye, you can get an eye back.”

And that's not all: they also consider him the Peter Pan of the animal world because he never ages. This is how Zambrano explains: “Unlike all amphibians that transform, which go from juveniles to adults, this one does not transform; it remains juvenile throughout its life and can reproduce. It has DNA ten times larger than that of a human being.”

The origin and history of axolotls are surrounded by mystery and fascination both for world science and for Mexican culture. “His story tells that he was a god (…) who was being persecuted (…) and became a water monster and took refuge in the canals of Xochimilco,” says Azael Meléndez, a farmer from Mexico City.

The conservation of Xochimilco, key to axolotls

Its characteristics mean that the axolotl lives only in water, on the banks of lakes. Its habitat is Xochimilco, the only wetland that survives in Mexico City since the time of the Aztecs.

“Xochimilco is fundamentally a wetland where we have placed islands of mud to allow agricultural production,” says Zambrano. In these channels, biodiversity increased greatly until, in the middle of the last century, it changed. “This ended (…) due to water contamination, because we brought carp and tilapia, because there is urbanization and axolotls don’t like to live with humans. And then we are losing Xochimilco”, summarizes the researcher.

The axolotl is in danger of extinction. The numbers are eloquent: in less than two decades, says the expert, they went from a population of 6,000 inhabitants per square kilometer to one of 36 per square kilometer.

To reverse the situation, the team of researchers that Zambrano is part of works in a laboratory with a colony of 120 axolotls.

“In this laboratory, conditions are maintained throughout the year so that we can reproduce them (…). Here the intention is to monitor the animals that have identification chips and make a selection”, says Horácio Mena, veterinarian at the UNAM Ecological Restoration Laboratory.

The 'chinampa refuge'

At the same time, these researchers work on restoring Xochimilco with the support of local farmers. The goal is to transform each mud island, known as a chinampa, into a safe habitat for axolotls.

In the canals, “we placed a barrier that prevents the passage of carp and tilapia, which are invasive species that cause us a lot of problems. As soon as we are sure that we do not have carp and tilapia inside these channels or shelters, the rehabilitation process with plants begins”, explains Carlos Sumano, field collaborator at the UNAM Ecological Restoration Laboratory.

Researchers monitor water quality so that it is clean and rich in insects and zooplankton, food for axolotls.

As part of their work, researchers release axolotls into refuge chinampas, where they can breed. They also seek to encourage neighbors to clean their canals and welcome axolotls.

There are currently 35 refuge chinampas in more than 7,000 meters of rehabilitated canals.

Zambrano considers that it is essential to understand that the effort goes far beyond the axolotls: “If we manage to restore the axolotl, which in general terms is political and social will, because it is not particularly expensive, we have hope and we have this to say: 'If we value our environment, if we value our biodiversity, then it is this biodiversity that will allow us to survive.'”