Located in the Seychelles archipelago, over 1,100 kilometers southwest of Mahé, Aldabra is one of the largest coral atolls in the world. It is composed of a ring of four main islands surrounding a vast, largely inaccessible lagoon. This geographic isolation has played a significant role in preserving its natural environment, which has remained mostly untouched by human activity.

Aldabra was formed by coral reefs that developed on the rim of a collapsed volcanic structure. This ring-shaped formation encloses a complex ecosystem of mangrove forests, lagoons, channels, reefs, beaches, and emerging coral islets. The atoll’s land area is approximately 155 square kilometers, while its protected marine zone covers over 2,500 square kilometers.

Recognized as a UNESCO World Heritage Site since 1982, Aldabra is known for its remarkable biodiversity. It is home to the world’s largest population of giant tortoises, with about 100,000 individuals of the species Aldabrachelys gigantea, closely related to the famous Galápagos tortoises. The atoll also supports a rich birdlife, including several endemic species such as the Aldabra rail, one of the few remaining flightless birds in existence.

The marine ecosystem is equally diverse, with healthy coral reefs, numerous reef fish, sharks, manta rays, and occasional sightings of dugongs. Aldabra’s waters serve as nesting grounds for several marine species, particularly green and hawksbill sea turtles that come ashore to lay their eggs on the beaches.

Access to the atoll is strictly regulated. There are no permanent residents apart from the scientific personnel of the Seychelles Islands Foundation, which manages the site. These restrictions aim to minimize environmental disturbances, including those from tourism or fishing. The atoll’s geographic remoteness, coupled with such protective policies, has helped maintain its relatively undisturbed natural state.

However, Aldabra is not immune to threats. Climate change, especially sea level rise, ocean acidification, and coral bleaching events, poses growing concerns for the resilience of its ecosystems. Ongoing research and environmental monitoring programs aim to better understand these challenges and anticipate their impacts.