Overview
- The Seychelles Islands Foundation and the University of Exeter published an atoll‑wide survey in October 2026 that estimated about 180,000–183,000 adult and subadult Aldabra giant tortoises on Aldabra Atoll.
- Researchers used a Bayesian hierarchical distance‑sampling method to model detection probability and correct for animals missed in dense vegetation, producing the first rigorous population baseline for the atoll.
- The study found the population was relatively stable over the 2018–2022 survey period and now exceeds the Seychelles human population of roughly 122,000 people.
- Scientists and SIF warn that longer droughts, rising seas and predation of eggs and hatchlings by invasive cats and black rats still threaten recruitment, and plans are in place to eradicate remaining invasives and keep monitoring the atoll.
- The count caps a multi‑decade recovery that began after 19th‑century overexploitation and was supported by strict reserve status in 1981, UNESCO listing in 1982 and management actions such as the 2012 goat eradication, while researchers say ongoing protection is essential to sustain the species and its role shaping Aldabra’s ecosystem.