Jellyfish Lake

Jellyfish Lake sits on Eil Malk (Mecherchar) island in the Rock Islands of Palau, a marine lake connected to the surrounding sea through fissures in the limestone. It is known for its population of golden jellyfish that migrate across the lake following the sun, having evolved with a much reduced sting since predators are largely absent. Scuba diving is not permitted here; visitors snorkel instead, staying within the top layer at around 5 metres or less, which suits beginners, as the jellyfish are fragile and the deeper layers of the lake contain hydrogen sulphide that is hazardous to breathe. Access is by a short walk from a dock over the ridge separating the lake from the lagoon, and visits are managed through permits issued by Palau's Rock Islands authorities.

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

• Entacmaea medusivoraReported here · unconfirmed
• Orbicular CardinalfishSphaeramia orbicularisReported here · unconfirmed
• Small Giant ClamTridacna maximaReported here · unconfirmed
• Grey Reef SharkCarcharhinus amblyrhynchosObserved near here · iNaturalist
• Napoleon WrasseCheilinus undulatusObserved near here · iNaturalist
• Papuan Spotted JellyMastigias papuaObserved near here · iNaturalist
• Whitetip Reef SharkTriaenodon obesusObserved near here · iNaturalist