ARI SHAPIRO, HOST:
We've got some good news for axolotls. Those are adorable little amphibians with feathery gills and cartoonish smiles. The salamanders were once found in lakes and wetlands throughout central Mexico. Now they've largely disappeared, and they are critically endangered. One estimate says fewer than a thousand adults remain in the wild. But a new study suggests axolotls could have a chance at a comeback. Here to tell us more is Alejandra Ramos. She is the lead author on that study, out in the journal PLOS One. Welcome to ALL THINGS CONSIDERED.
ALEJANDRA RAMOS: Thank you so much for having me.
SHAPIRO: OK, so you and your team took 18 axolotls raised in captivity and released them into the wild. What happened?
RAMOS: Well, we were pretty amazed because, first of all, they all survived, which we were a bit worried about because these axolotls, as you said, they were raised in captivity, and when you have captive animals, they lose a lot of behaviors that they need to survive in the wild. For example, our axolotls had never been exposed to predators. So when you don't have the antipredatory behaviors, that means that if a snake appears or some sort of predator, then the axolotls might not react. Like, they might not escape or they might not seek refuge, and then they can be more easily predated.
SHAPIRO: But these axolotls are all thriving? All 18 of them?
RAMOS: Yeah, they all survived, and the ones that we were able to capture after our study finished, they had actually gained weight. So that was a really good result because that means not only are they evading predators, but they're also successfully hunting and finding prey in the wild.
SHAPIRO: So this is a big discovery, that captive-raised axolotls can survive in the wild. Will you tell us a little bit more about why they are so distinct? I mean, people think they're cute, they're adorable. What is it that interests you about them? Why do you think it's important to save this species in particular?
RAMOS: Well, this species is really, really important in Mexico. They're part of our culture. They're part of, like, our history because they were actually living in Lake Xochimilco when the Aztecs were there. Lake Xochimilco is, like, their native habitat, and they're endemic to it, and it's the only place in Mexico where they actually live. So they're really important in that sense. But they're also very important in biomedicine research because this particular species has the abilities to regenerate their gills and their limbs. So they're also really special for biomedicine and for Mexicans. And as you said, they are adorable, so people all over the world just love them.
SHAPIRO: If axolotls are endangered, at least in part because of pollution or habitat destruction, does releasing them into the wild actually make a long-term difference?
RAMOS: Yes, but only if you restore the habitat where you're going to release them. If you do not make this restoration effort, then they're going to die again. And actually, that's a really sad thing because there's other people that are working with axolotls, and axolotls are really easy to raise in captivity. That's not the problem. But the problem is, if these axolotls that you raise in captivity you release in areas of Xochimilco that have not been restored, then yeah, they're going to die again.
SHAPIRO: There are many endangered species all over the world. Are there broader takeaways here about how to keep other species from going extinct?
RAMOS: Yes. Yes, thank you for asking this. There are so many species that are struggling, and probably the main problem is habitat loss. So many animals are losing their habitats and their houses all over the world. So, this study also shows, like, if you make an effort to restore wetlands or other type of habitats, that you can actually help nature come back. Oh, because another cool thing about our study is that once we restored them for the axolotls, the local people noticed that other species that they hadn't seen in many years started to come back to the area.
SHAPIRO: That's Alejandra Ramos, a science faculty member at the Autonomous University of Baja California in Mexico. Thank you so much.
RAMOS: Thank you. Transcript provided by NPR, Copyright NPR.
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