Blue Hole Palau

Blue Hole is one of the well known sites in Palau's Rock Islands, near Ngemelis, and it is usually dived alongside the adjacent Blue Corner given their proximity. Divers descend through four vertical shafts in the reef top that open into a large sunlit cavern, then exit through a swim-through into the outer wall, which drops away steeply into deep water. Inside the chamber depths run roughly from the surface down to about 30 metres before the exit into open reef, and the interior offers a change of light and scenery from the reef wall itself. It is generally considered suitable for divers with some experience because of the cavern navigation and the need to manage buoyancy and depth through the swim-through. Soft corals, reef fish, and occasional grey reef sharks are commonly reported on the outer wall section connected to the hole.

Confirmed by our research team, reported by independent divers, or observed nearby via iNaturalist — each entry is labelled with its source.

• Whitetip Reef SharkTriaenodon obesusReported here · unconfirmed
• Napoleon WrasseCheilinus undulatusReported here · unconfirmed
• Harlequin SweetlipsPlectorhinchus chaetodonoidesReported here · unconfirmed
• Clown TriggerfishBalistoides conspicillumReported here · unconfirmed
• Bigeye TrevallyCaranx sexfasciatusReported here · unconfirmed
• Midnight SnapperMacolor macularisReported here · unconfirmed
• Bignose UnicornfishNaso vlamingiiReported here · unconfirmed
• Redtooth TriggerfishOdonus nigerReported here · unconfirmed
• Humpback SnapperLutjanus gibbusReported here · unconfirmed
• Grey Reef SharkCarcharhinus amblyrhynchosObserved near here · iNaturalist
• Hawksbill Sea TurtleEretmochelys imbricataObserved near here · iNaturalist