Once near extinction, these giant tortoises now outnumber people in the Seychelles, survey finds

LONDON — Giant tortoises once pushed to the brink of extinction now outnumber humans in their home of the Seychelles, according to a new survey on one of the African nation's most remote islands.

The survey, led by the Seychelles Islands Foundation and the University of Exeter in the UK, estimated that about 180,000 Aldabra giant tortoises live on Aldabra Atoll, an Indian Ocean island group off the east coast of mainland Africa.

It is the highest figure ever recorded for the species, and far exceeds the human population of around 122,000 living in the tiny archipelago nation.

Aldabra Atoll is one of only two places in the world where giant tortoises are found in the wild. A much smaller population lives on Ecuador's Galápagos Islands.

One of the world's most undisturbed island ecosystems, Aldabra Atoll is home to several unique species that thrive in the remote haven.

The species has rebounded from a dramatic decline. Heavy exploitation during the 19th century reduced its population on the island to fewer than 1,000, pushing the species to the brink of extinction.

A recovery program helped secure strict nature reserve status for the atoll in 1981. It became a UNESCO World Heritage site a year later, giving the population room to rebound.

"More than 180,000 giant tortoises roaming freely on our atoll is proof of what long-term commitment to conservation can achieve," Frauke Fleischer-Dogley, CEO of SIF, said in a statement.

"This is wonderful news for Seychelles, for the world, and for everyone who has worked to protect Aldabra."

Creating the new estimate required more than just a headcount. The figures are based on an analysis of five years of tortoise counts conducted between 2018 and 2022, and are the first update since a widely cited estimate of 100,000 tortoises in the late 1990s.

"Aldabra's giant tortoise monitoring program is one of the longest-running in the region, but the atoll's dense vegetation makes counting tortoises genuinely difficult in places," said Nancy Bunbury, one of the study's co-authors.

Bunbury added that the team of scientists has produced the most reliable baseline for the species, which can be used as a benchmark to track its population for decades to come.

Despite the encouraging population estimate, the study's authors said continued vigilance is crucial as the climate crisis brings longer and more frequent droughts that could reduce shade and food for the tortoises. Rising sea levels as the planet warms also threaten the atoll's low-lying habitat.

The world's oldest known tortoise, a 194-year-old named Jonathan, likely came from the Aldabra Atoll or the Granitic Seychelles.

Guinness World Records lists Jonathan as the oldest living land animal and the oldest tortoise ever. He was believed to be about 50 years old when he was moved to the British Overseas Territory of St. Helena in 1882.

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