“Alien” tortoises offer second chance to species thought extinct

More than a century after the Floreana giant tortoise was declared extinct, scientists have uncovered an extraordinary twist in its story: descendants of the vanished species were found living on a remote Galápagos volcano and are now being returned to the island where their ancestors once roamed.

The discovery is part of an ambitious conservation effort in the Galápagos Islands, where giant tortoises have survived for millions of years but suffered devastating losses after pirates and whalers began visiting the archipelago in the 16th century, CNN Science writes. 

According to CNN, between 100,000 and 200,000 giant tortoises disappeared over just two centuries. Their ability to survive for up to a year without food or water made them especially valuable to sailors, who could keep the animals alive aboard ships as a source of fresh meat.

“And when these people wanted to eat, the tortoises were simply there, ready to go, and they had fresh meat,” Jorge Carrión, conservation director at the Galapagos Conservancy, told CNN.

The first Galápagos tortoise to become extinct was the Floreana tortoise, around 1850. The species was distinctive for its pronounced “saddle” shaped shell.

“They were very unusual tortoises, with a really pronounced shape — what we call a ‘saddle’ shape — that isn’t found anywhere else on the planet,” said James Gibbs, vice president of Science and Conservation at the Galapagos Conservancy and a professor at the State University of New York.

Then, in 2000, Gibbs and other researchers encountered unusual tortoises on Wolf Volcano, the highest point in the Galápagos.

“There were thousands of native species there … but it quickly became clear that there were also some strange tortoises,” Gibbs recalled.

Researchers initially called them “aliens” because they could not determine where they came from. Genetic testing later revealed that the animals belonged to the Floreana lineage.

Scientists believe humans may have inadvertently transported the tortoises to Wolf Volcano. Pirates and whalers routinely carried dozens or hundreds of tortoises aboard ships, and some may have been discarded when vessels exceeded their weight limits.

Nineteen of the animals were eventually transferred to the Fausto Llerena Land Tortoise Breeding Centre, where conservationists began breeding them.

The programme has produced remarkable results. The tortoises have already produced about 800 young and continue to reproduce at an average rate of 60 babies a year, Gibbs said.

In February 2026, 158 young tortoises were released on Floreana Island, equipped with satellite tracking devices. With support from NASA, scientists selected areas they believed would provide suitable habitat for the animals and potentially allow them to establish nesting populations.

The released tortoises are hybrids, carrying genetic material from Floreana tortoises and native tortoises from Wolf Volcano. Scientists have yet to find a pure Floreana tortoise, but Gibbs believes some may still survive in the volcano’s vast landscape.

“We haven’t yet found a pure Floreana tortoise, but we believe they exist,” Gibbs explained.

The animals are important far beyond their own survival. Conservationists describe giant tortoises as “ecosystem engineers” because they disperse seeds, reshape vegetation and create spaces used by other species.

“They grow slowly, yes, but they are very constant and persistent. It’s like the fable of the tortoise and the hare: in the end, the tortoise wins the race,” Gibbs said.

For conservationists, the tortoises’ return offers a powerful reminder that extinction is not always the end of the story. As Gibbs put it: “They are such resilient, long-lived, and tenacious creatures that they have, in fact, allowed us to solve some of the problems we have created.”

By Sabina Mammadli