Dive Site: Grand bancs

About Grand bancs

Grand Bancs is a notable dive site located in the Nosy Be region of Madagascar, characterized by its extensive coral formations and significant depths. It features plateaus that rise to 13 to 16 meters from the surface, dropping off dramatically to depths of 27 to 40 meters, and even beyond 60 meters along its fault line. This site is distinguished by abundant coverage of both fan and table corals, creating a rich underwater landscape. The topography includes steep drop-offs punctuated by numerous caves and smaller cavities. These sheltered areas provide habitat for various marine species, including hawkfish, fry, and shrimp, often adorned with vibrant alcyonarians. The site is a dynamic environment, with strong currents sometimes creating exhilarating drift dive conditions. These currents attract a wide array of pelagic life, making sightings of king mackerel, trevally, tuna, and various sharks common. Grand Bancs is also a seasonal hotspot for megafauna; humpback whales are observed calving from August to October, while manta rays, mobula rays, and whale sharks visit between September and December to feed on plankton. Diving at Grand Bancs often involves planning for drift entries due to variable currents. Divers are advised to maintain close proximity to their group. The site offers a rich experience, combining stunning coral reefs with opportunities for pelagic encounters, suitable for divers comfortable with moderate to strong currents.

Dive site facts: Grand bancs

Depth

13–60 m

Current

Moderate

Entry

Liveaboard or dayboat

Level

Intermediate

Dive type

Reef, Reef

Region / port

Madagascar

Coordinates

13.4333° S, 47.8833° E

Conditions & Currents

Grand Bancs experiences moderate to strong currents, which can vary depending on tidal conditions. These currents often necessitate drift entries, and divers should plan to stay close to their group for safety. The dynamic flow contributes to the abundance of pelagic life but requires a comfortable level of experience and good buoyancy control. Visibility at the site typically ranges from 10 to 40 meters, though plankton blooms, especially during warmer months, can reduce it while attracting large filter feeders. Water temperatures range from 24°C in cooler months to 28°C in warmer periods. Divers should be prepared for varying conditions and plan their gas accordingly, as deeper sections of the site extend beyond 60 meters.