Aldabra Atoll in the Seychelles archipelago is now home to around 183 thousand adult and subadult giant tortoises of the species Aldabrachelys gigantea. This is the largest wild population of the species in the world, and for the first time in centuries it has surpassed the number of people in the entire territory of the Seychelles.
The new data come from five years of monitoring from 2018 to 2022, conducted by the Seychelles Islands Foundation and the University of Exeter. The scientists applied a statistical model that accounts for animals hidden by vegetation and obtained the first reliable estimate for the entire atoll in decades. Previously, a figure of around 100 thousand was often cited, but it did not reflect the real picture.
Back in the nineteenth century, intensive hunting and meat harvesting by sailors reduced the population to fewer than a thousand individuals. The protection of the atoll as a strict nature reserve since 1981 and its status as a UNESCO World Heritage Site since 1982 have allowed the species to recover. Today the tortoises graze freely on the “tortoise meadows,” and their numbers remain stable.
Aldabra is one of two places on the planet where giant tortoises have survived in the wild. The second is the Galápagos, but there the population is considerably smaller. The success on Aldabra shows how long-term conservation efforts and the fight against invasive species can bring a species back from the brink of extinction.
At the same time, risks remain: droughts, rising sea levels and continuing threats from rats and cats. Monitoring continues, and the data underscore the importance of constant attention to isolated ecosystems.
The story of the Aldabra tortoises is a reminder that nature can recover when humans stop depleting it and begin to protect it systematically.
