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Giant Tortoises Outnumber Humans in Stunning Seychelles Discovery
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Moneycontrol•08-10-2026, 14:50
Giant Tortoises Outnumber Humans in Stunning Seychelles Discovery
- •Scientists estimate that nearly 183,000 adult and sub-adult Aldabra giant tortoises live on Aldabra Atoll in Seychelles, surpassing the human population of the island nation.
- •Researchers used advanced statistical methods like Bayesian hierarchical distance sampling to account for tortoises hidden by dense vegetation.
- •The new estimate does not mean the population doubled since the 1990s; rather, older surveys likely underestimated the actual numbers due to different methodologies.
- •The findings challenge the assumption that the atoll had reached its ecological carrying capacity in the late 1900s.
- •Heavy exploitation in the 19th century reduced the tortoise population to fewer than 1,000, but decades of strict conservation have driven a remarkable recovery.
Key Questions Answered
Scientists have estimated that nearly 183,000 adult and sub-adult Aldabra giant tortoises live on Aldabra Atoll in Seychelles, which is higher than the human population of the Seychelles.
Researchers used a statistical method called Bayesian hierarchical distance sampling to account for tortoises that were present but missed because they were hiding in vegetation or shade.
Heavy exploitation in the 19th century reduced Aldabra's giant tortoises to fewer than 1,000 animals before protection allowed them to recover, leading to the atoll becoming a strict nature reserve in 1981 and a UNESCO World Heritage Site in 1982.
