Turtle Cavern

Sipadan Island sits off the coast of Sabah in Malaysian Borneo, in the Celebes Sea, and is known for its steep drop-offs rising from the seabed a short distance offshore. Turtle Cavern is a cave system on the island reaching a maximum depth of around 18 metres, rated an intermediate dive over a cave bottom. Divers have reported turtle skeletons within the cave passages, a reminder that turtles sometimes swim in and lose their way out, and cave diving itself is treated as a hazard here given the overhead environment. Along the surrounding reef, divers have also noted angelfish, clownfish, fusiliers, nudibranchs, octopus, parrotfish, and trevally. Access to Sipadan itself is tightly controlled by permit, with divers typically staying on nearby islands such as Mabul or Kapalai and taking boats out to the site.

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

• OctopusOctopusReported here · unconfirmed
• TrevallyTrevallyReported here · unconfirmed
• NudibranchNudibranchReported here · unconfirmed
• FusilierFusilierReported here · unconfirmed
• ClownfishClownfishReported here · unconfirmed
• ParrotfishParrotfishReported here · unconfirmed
• AngelfishAngelfishReported here · unconfirmed
• Whitetip Reef SharkTriaenodon obesusReported here · unconfirmed
• Bigeye TrevallyCaranx sexfasciatusReported here · unconfirmed
• Napoleon WrasseCheilinus undulatusReported here · unconfirmed
• Harlequin SweetlipsPlectorhinchus chaetodonoidesReported here · unconfirmed
• Blueface AngelfishPomacanthus xanthometoponReported here · unconfirmed
• Bluefin TrevallyCaranx melampygusReported here · unconfirmed
• Paletail UnicornfishNaso brevirostrisReported here · unconfirmed
• Pinktail TriggerfishMelichthys viduaReported here · unconfirmed
• Green Sea TurtleChelonia mydasObserved near here · iNaturalist
• Blue DragonPteraeolidia semperiObserved near here · iNaturalist
• Dusky NembrothaNembrotha kubaryanaObserved near here · iNaturalist