Mergui Archipelago dive sites

Manta rays are present throughout the November-to-April diving season, but sightings peak between February and April when plankton concentrations are highest. The west and southwest faces of the rock are the primary manta cleaning and feeding stations.

Black Rock stands alone approximately 188 km northwest of Kawthaung and 114 km west of the Myanmar coastline. It is accessible only by multi-day liveaboard cruises, typically combined with other Mergui Archipelago dive sites over 5 to 10 day itineraries departing from Phuket or Ranong in Thailand.

Strong and unpredictable currents are the main challenge, particularly on the exposed west and south sides where the wall drops steeply into 300-meter depths. Surge around the rock can be significant. Advanced certification and experience with current diving are essential. The site's remoteness also means the nearest decompression chamber is in Phuket.

Yes, the main cavern at Shark Cave is a wide, shallow cavern rather than a true cave, meaning natural light is always visible from inside. The ceiling is high enough to avoid contact, and the sandy floor provides a clear reference point. Intermediate-level divers with good buoyancy control can safely explore the cavern. However, it is important not to stir up the sandy bottom, which can reduce visibility inside the cavern. Your dive guide will brief you on entry and exit routes.

Tawny nurse sharks use the cavern as a daytime resting site and are present on the majority of dives, typically in groups of three to eight animals. They rest on the sandy floor with their heads tucked under the rock overhangs. Bamboo sharks are also common, often found in the shallower recesses. Whitetip reef sharks patrol the outer reef edge. The sharks are habituated to divers but should be given respectful distance to avoid disturbing their rest.