Shark Cave

The cave starts on the northwest corner of the island at 5 m below the surface, as a large cavern entrance that drops down to 16 m. The ragged mouth is often crowded: long-fin trevally and silver sweetlips stacked in it, grey reef sharks holding at the edge, and groups of whitetip reef sharks that can make a surprising appearance. Inside, the cavern gradually narrows into a tunnel about 20 m long that runs through to the east side of the island.

Part way through, a one-metre square hole marks the entrance to the lower cavern where the resident nurse sharks lie up. It is accessible one diver at a time and real care is needed with buoyancy control. Surge moves through the passage and can make navigating the tunnel tricky at times, so groups work through it in order rather than as a bunch, and each diver waits for the one ahead to clear the hole before following.

Most divers exit the tunnel on the east side and turn left, to the north, where a sloping reef down to 25 m is covered with hard and soft corals. Black-blotched fantail rays and black and white banded sea snakes hunt over it, and the cracks in the wall hide nocturnal grey bamboo sharks — a small species about half a metre long — along with rock lobsters and frogfish. If the current permits, the southernmost outcrop of the three, The Pinnacle, drops below 30 m and is small enough to circle in a single dive.