Aldabra Group dive sites

Aldabra Atoll is located approximately 1,100 kilometres southwest of Mahe, the main island of Seychelles. It is accessible only by expedition liveaboard or private yacht, with voyages typically lasting 10-14 days and covering Aldabra along with other remote outer islands like Astove and Cosmoledo. Prior approval from the Seychelles Islands Foundation is required to visit this UNESCO World Heritage Site.

Aldabra's extreme remoteness means its marine ecosystem is among the most pristine on the planet. The atoll receives fewer than 1,000 divers per year, so coral reefs are in near-perfect condition and marine life shows virtually no fear of humans. Encounters with large pelagic species including manta rays, tiger sharks, and hammerheads are common, and the sheer biomass of fish on the reef is staggering compared to more accessible sites.

The two prime windows are March to May and October to November, during the transitional periods between monsoon seasons when seas are calmest. The southeast monsoon from May to September brings rougher seas, while the northwest monsoon from December to February can also create challenging conditions. Manta ray sightings peak during the transitional months.

Aldabra is one of the most remote atolls in the Indian Ocean, lying over 1,100 kilometres southwest of Mahe. Access is exclusively by liveaboard or expedition yacht, typically departing from Mahe or Assumption Island. Only a handful of operators hold permits from the Seychelles Islands Foundation, and trips run sporadically, usually two to four departures per year. The voyage from Assumption takes roughly eight hours. There are no facilities, accommodation, or emergency services on Aldabra itself, so expeditions must be entirely self-sufficient including a recompression chamber on board.

The south side of Aldabra is exposed to open Indian Ocean swells and the channels produce currents that can exceed three knots on spring tides. A minimum of 100 logged dives including significant current and drift experience is required by most operators. Many recommend technical diving certification as depths along the outer wall quickly exceed 40 metres. Surface conditions can be rough, making boat entries challenging. All divers must carry redundant air sources, surface marker buoys, and be comfortable with negative entries in moving water.