Because large populations of captive axolotls exist, they will not go entirely extinct. Reintroduction of the species is unlikely for many reasons, primarily because they would have less genetic diversity and would be more susceptible to a fungal disease called chytridiomycosis, which can be fatal to amphibians and is very difficult to cure. It has currently infected thirty percent of all amphibian species.
There are seven species of axolotls, but only the Mexican axolotls never lose their gills. The others are capable of never "growing up" and coming out of the water, but they only stay larvae if the temperature is too cold for them to become adults. The carnivorous Mexican axolotls can live up to fifteen years. Like some lizards, they can replace lost body parts and are therefore used in scientific research. They grow up to 1 foot long and are currently specified as critically endangered.
But there is a chance that the axolotls will not go extinct in the wild. Scientists are working to create new refuges for the animals to live in, so that their numbers do not continue to fall and, ultimately, so that the cute creatures will survive in nature.