Shark Bank
Depth is the range from the top of the site to its usual maximum; "recommended cert" is the mainstream-agency level operators usually ask for, not a legal rule. Currents and visibility change daily — treat everything here as planning ranges.
Shark Bank is Mahé's big-fish dive: a granite rise far enough offshore that everything on it comes in extra size. Marbled rays the width of car hoods rest between the boulders, yellow snapper and big-eye trevally form permanent walls over the plateau, and barracuda hang up-current in the ranks. The name overpromises on sharks these days — whitetips and the odd passing whale shark in season, not reliable schools — but the site's mass of fish, granite architecture, and open-water character keep it at the top of the island's list. Current and the deep, referenceless descent make it an advanced trip.
The moment you come for: Huge marbled rays; permanent snapper and trevally walls over granite
Topography: Granite plateau and boulder field rising from deep sand well offshore of Mahé
Current: An offshore plateau with current on most tides; the crossing from Beau Vallon takes half an hour or more.
Know before you splash
Hazards: Current, open-ocean surface conditions, and a bottom that starts below 14 meters.
Conservation: Wild encounters only; operators run no feeding of any kind.
Nitrox: Worth it here — profiles sit in the range where enriched air meaningfully extends no-stop time (with the training to use it).
Who you'll meet
Giant Moray Eel
Great Barracuda
Marbled Ray
Spotted Eagle Ray
Whale Shark
For photographers
Wide angle: ★★★★☆ · Macro: ★★☆☆☆ — editors' 1–5 rating of what this site gives each style of shooting