Giant tortoise numbers on Aldabra reach the highest count on record

Aldabra Atoll, a ring of coral islands in the Indian Ocean east of Africa, has been counted at about 180,000 giant tortoises, the highest figure ever recorded there. The researchers' best estimate for adult and sub-adult animals is nearly 183,000. The study was led by the Seychelles Islands Foundation and the University of Exeter, and drew on counts taken between 2018 and 2022, a period when the population stayed relatively stable. The number most often quoted until now was about 100,000, from the late 1990s. The recovery matters because fewer than 1,000 tortoises were thought to remain on the atoll in the 19th century. The findings were published in the journal Ecology and Evolution. The original news report and the study itself carry the full methods and caveats.