Due to the restricted current flow, diving inside the remains of the volcanic caldara is not very exciting when compared to that of the surrounding reefs. Among the great variety of marine species here, the large number of many different coloured Frogfish of various sizes stands out. Large aggregations of Horned Sea Stars spawning on shallow sand are common.
Gold-specked Jawfish are everywhere. Very little studied, these Jawfish (Opistoåågnathus Spp.) lie tail first in vertical burrows with only their heads facing out to catch passing plankton. Some share burrows with shrimps but the relationship is not clear. Their heads and mouths are enlarged and some are seen to carry eggs in their mouths.
With so many patches of sand, Garden Eel (Heteroconger Spp.) colonies are common, these shy creatures withdraw into the sand at the approach of divers. The colonies thrive in areas where strong incoming and outgoing tides carry zooplankton, which the eels snatch up as it passes.
A special permit is required to visit the pearl farm where visitors have to be particularly careful on the pontoon jetty. Hundreds of sea snakes using the jetty for shade congregate in the space between the floating barrels and the top planking.
Nowadays most pearls are cultivated by man. The pearl oysters are placed six a time in wire baskets, suspended from a latticework of artificial fibre ropes. At a year and a half, the oysters are carefully slit near the gonads and a small bead carved from another shell is carefully inserted. After a further three years the pearls are harvested.