Con Dao Archipelago

Trevally pass through the outer sites, particularly the more exposed northern reefs. Con Dao does not have documented schooling aggregations of the kind seen in the Coral Triangle.

Con Dao holds what is likely Vietnam's last dugong population, and a 2023 survey by the Institute of Marine Environment and Resources estimated only about 12 animals remained. Their seagrass has collapsed — from over 329 hectares across 12 locations to two remaining areas, Con Son Bay and Bay Canh, by 2022 — and further deaths were reported in 2025. Divers essentially do not see them. Sightings are opportunistic ranger observations in shallow seagrass, not dive encounters, and the seagrass beds are inside strictly protected zones. Treat this as a conservation fact about Con Dao, not a reason to book a dive.

One of four sea turtle species the park records at Con Dao, alongside green, olive ridley and loggerhead. Far less numerous than green turtles and seen only occasionally on reef dives.

Blue-spotted rays are reported on the sand and rubble patches at Hon Cau and Bay Canh. Operators do not distinguish species reliably, so some sightings may be the similar-looking bluespotted maskray rather than Taeniura lymma.

Morays are a standard part of the Con Dao reef fauna, holed up in the hard coral structure. Species identification in operator reports is loose, so not every large moray seen is Gymnothorax javanicus.

Large solitary barracuda are reported on the outer sites; the local operator also mentions loose schools. Not a site-specific aggregation.

Anemonefish are on nearly every Con Dao reef dive and are one of the more dependable subjects here. Species-level identification in local reporting is not reliable.

Reported by the local operator on the deeper edges at Bay Canh and Hon Cau, usually in small groups.

The most reliably reported shark at Con Dao, cited by local operators on the shallow reefs at Hon Cau and Bay Canh. It is small and resting, not a pelagic encounter. Con Dao has no dependable big-shark diving.

Con Dao is Vietnam's most important green turtle rookery — around 450 nesting females a year across 18 beaches covering about 24 hectares, with Bay Canh the main site. Nesting peaks May to October, though the park reports some nesting year-round. Note the headline experience is a beach-based, ranger-led night-time nesting and hatchling-release programme on Bay Canh, not a dive. Underwater, turtles are seen on reef dives at Bay Canh and Hon Cau but are not guaranteed. Park rangers have assisted over 21,000 nests since 1995 at a hatching rate above 80%, releasing about 150,000 hatchlings a year.

The deeper zones at Hon Cau's Shark Fin site are specifically described as nudibranch-rich. Macro is the realistic strength of Con Dao diving, given the shortage of large animals.

Con Dao's reefs mix hard coral gardens with soft coral, and 2022–2023 benthic surveys recorded 41 coral genera here, the highest documented in Vietnam. Set expectations against the 2024 bleaching event, which hit about 97% of coral cover at 2–5m — condition on any given dive may be much poorer than pre-2024 descriptions suggest.