Chuuk Lagoon

Chuuk Lagoon, in the Federated States of Micronesia, is a large barrier-reef lagoon best known for the wrecks of Operation Hailstone, the February 1944 American air raid that sank much of the Japanese Imperial Navy's fleet anchored there. Dozens of freighters, tankers, and warships still lie across the lagoon floor, many still carrying cargo such as tanks, aircraft parts, munitions, and personal effects, making it one of the most significant wreck-diving destinations anywhere. Depths and conditions vary considerably between individual wrecks, from shallower hulls to deeper ones requiring technical training to reach safely. Diving here is classed as advanced, reflecting the depths involved, the penetration opportunities inside the wrecks, and the care needed around silt and structural hazards.

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

• Lined BristletoothCtenochaetus striatusReported here · unconfirmed
• Whitemargin UnicornfishNaso annulatusReported here · unconfirmed
• Pacific Longnose ParrotfishHipposcarus longicepsReported here · unconfirmed
• Bleeker's ParrotfishChlorurus bleekeriReported here · unconfirmed
• Brown Staghorn CoralAcropora muricataReported here · unconfirmed
• Humpnose Bigeye BreamMonotaxis grandoculisReported here · unconfirmed
• Barred RabbitfishSiganus doliatusReported here · unconfirmed