Tara’s axolotl rescue centre has about 160 of the amphibians, as well as ferrets, snakes and lizards.
She said demand surged after axolotls appeared in Minecraft, with breeders “going absolutely crazy” producing them in large numbers.
“Everyone’s kids wanted one – it was seen as such a big money-maker,” she said.
But now, some owners are giving them up and the centre received 160 axolotl from one overwhelmed owner.
Young axolotls must be kept separately for months due to cannibalistic behaviour and therefore not yet ready to be re-homed, she said.
Tara said a key part of her role was “vetting new homes”, ensuring tanks are properly set up and water conditions are correct – something that can take up to 12 weeks – putting the animals at risk.
“It’s quite in-depth and can be overwhelming, but we try to make sure they go to the best possible homes,” she said.
Tara said the creatures were a “big dedication” and were not “a big interactive pet”.
“You can feed and watch them, but if you want something hands-on, they’re not the right choice,” she added.
“They are majestic animals, but they’re critically endangered and losing their habitat in Mexico.
“In a decade’s time the only ones you’re going to be able to see are the ones that are domestically owned.”
The RSPCA urged anyone considering an axolotl, or any exotic pet, to think carefully before taking one on, and to thoroughly research the animals’ needs.
“Exotic pets often end up in our care, or others in the animal welfare sector, later down the line when people realise they’re not easy to care for, or once the novelty wears off,” a statement said.
“Potential owners need to make sure they can give their animal the environment they need and they have the facilities, time, financial means and long-term commitment to maintain a good standard of care.
“These amphibians need care and attention for their entire lives, which can be 15 years,” it added.