Axolotls need adopting

Hundreds of years ago, when the Mexica established themselves in what would become the capital of the Aztec Empire, they encountered an alien-looking creature with a permanent grin and a crown of feathery gills. Fascinated, they named it axolotl – water monster – and revered it as a mischievous god who shape-shifted into an amphibian to elude sacrifice.

Since then, the salamander with a Mona Lisa smile has become an icon of Mexican culture, and has inspired countless researchers because of its capabilities to regenerate bits of its body.

Though approximately 1 million of them can be found in laboratories and pet stores across the world, the axolotl is on the brink of extinction in the canals of Lake Xochimilco in southern Mexico City, its only natural habitat.

In hopes of preventing the annihilation of a species with mystifying traits, ecologists at Mexico's National Autonomous University are giving the public the chance to virtually adopt an axolotl.

For US$30, $180 or $360 (NZ$48, $290 or $580), donors can choose the sex, age and name of the little buddy they get to call theirs for a month, six months or a year, respectively. The axolotls stay in Mexico, but donors receive an adoption kit with an infographic, the axolotl’s identification card, a certificate of adoption, and a personalised thank-you letter.

The campaign also includes options to buy an axolotl a meal for US$10 (NZ$16) or to fix up one of their homes for US$50 (NZ$80). And for those wanting to splurge a bit more, participants can adopt the axolotl’s refuge of chinampas – the artificial islands that dot Lake Xochimilco – for one, six or 12 months, starting at US$450 (NZ$725).

The funds would go towards building refuges for the axolotl and restoring its habitat, which had been devastated by the effects of Mexico City's urbanisation over the last decades, said Luis Zambrano, an ecologist at Mexico’s National Autonomous University.

The city’s expansion and growing population have turned Lake Xochimilco into a shrinking, polluted matrix of canals throttled with hungry fish imported from other continents – both of which have depleted axolotl populations.

When scientists in 1998 conducted their first census of the axolotl population, there were about 6000 for every square kilometre in Lake Xochimilco. The last count, in 2014, showed there were only about 36 per sq km, Zambrano said.

Losing the axolotl in the wild “would be incredibly bad for both Mexican culture and the science world”, he said.

Axolotls are a scientific wonder. Even though amphibians typically go from egg to tadpole to land-roaming adult, the axolotl simply refuses to grow up, sticking to a life in the water, like a pseudo-tadpole. “That’s very attention-grabbing when it comes to understanding evolution,” Zambrano said.

Axolotls have the remarkable capability to restore lost body parts, from limbs to eyes to brains. This has made them a prime research subject in the areas of regeneration, ageing and cancer. They have also helped scientists understand how organs develop in vertebrates, uncover the causes of the birth defect spina bifida, and discover thyroid hormones.

The salamanders have also become beloved exotic pets.

Last year, when the adoption campaign first launched, it raised almost US$30,000, covering about 40 refuges. But to expand and continue to maintain them, the ecologists needed about 10 times more funding, Zambrano said.