A survey by the Seychelles Islands Foundation and the University of Exeter estimates that about 180,000 Aldabra giant tortoises live on Aldabra Atoll (a remote, protected coral island group in the Indian Ocean), the largest population ever recorded for the species and well above Seychelles' human population. The study, based on counts from 2018 to 2022 and published in Ecology and Evolution, found numbers stable, a striking recovery from fewer than 1,000 animals in the 19th century after the atoll was made a strict nature reserve in 1981. Researchers say the result is a major conservation success but warn that droughts, rising seas and invasive cats and rats could threaten the tortoises' future.