Wildlife of Moso Island · Vanuatu
A turtle appearing over the reef can become the moment you remember from a whole dive. Meet Moso’s green and hawksbill turtles, and discover why this island matters far beyond its shores.
The encounter
Reefs, wrecks and warm blue water bring divers to Moso Island. Along with the possibility of seeing a dugong, a wild sea turtle is one of the region’s most compelling marine-life encounters.
You might notice one resting near a ledge, moving along a coral slope or lifting towards the surface for air. Give it room and a few calm seconds; the best sightings are the ones in which the turtle carries on behaving like a turtle.
Two species matter most to Moso’s story: green turtles and hawksbills. Both use Vanuatu’s waters and both have nested on Moso. Their presence is real, but a sighting on any particular dive is never guaranteed.
Know your turtles
A shell can be brown, amber or beautifully marbled in either species. The head and the way the shell plates meet are more useful clues than colour alone.
Green turtle
Broad head · blunt beak · smooth shell outline
Green turtles often have a rounder face and shell plates that meet edge to edge. The name refers to the colour of their fat, not the colour of the shell. The diver-and-turtle photograph above shows a green turtle.
Hawksbill turtle
Narrow head · hooked beak · often overlapping shell plates
The hawksbill’s pointed beak helps it probe reef crevices for food. Its shell plates may overlap like shingles, with a more jagged rear edge. Moso’s north-coast beaches have a particularly important hawksbill nesting record.
Which is more common underwater? Published Moso research documents hawksbill nesting especially well. It does not provide a reliable, current comparison of green and hawksbill turtle numbers at local dive sites. The green turtles pictured here do not contradict Moso’s hawksbill nesting history.
An island with several turtle habitats
A turtle seen by a diver may be feeding, resting or travelling between habitats. Moso’s reef, sheltered shallows and nesting beaches each play a different part.
Hawksbills search reef structure for sponges and other invertebrates. Both species can use reef ledges and rocky areas to rest.
Green turtles forage in coastal seagrass habitat. Historic surveys recorded seagrass around Moso, although its present extent needs fresh mapping.
Moso’s quieter northern beaches are important nesting habitat, especially for hawksbills. Green turtles nest on the island too.
The nesting story
The north coast is recognised as an important hawksbill nesting area. Historical monitoring at Tassiriki counted 147 hawksbill nests in the 2008–09 survey season, then 93 in 2009–10 and 67 in 2010–11. Green turtle nests were also recorded in those years, though fewer at that monitored beach.
Vanuatu’s 2023 national turtle review says regular nesting surveys at Moso had lapsed. Those earlier figures show the island’s significance, but they cannot establish a current trend or tell us how many turtles a diver will see.
An ocean-wide story
The turtles that nest on Moso need protection far beyond the island.
Researchers satellite tagged seven female hawksbills after they nested on Moso between 2018 and 2020. Three travelled to feeding areas in New Caledonia, three headed towards Australia’s Great Barrier Reef, and one reached the waters near Aneityum in southern Vanuatu. Some transmitters stopped before the turtles’ final destinations could be confirmed.
That published Moso tracking study followed a small group of known nesting females. It reveals extraordinary journeys; it does not tell us where every turtle seen on a Moso dive was born or how many live around the island.
Better encounters
Vanuatu’s turtle-interaction guidance starts with a simple move: stop, watch and give the animal a choice.
Hold position rather than swimming directly at a turtle. Let it continue feeding or resting.
Stay at least about 3 metres away. Groups of more than three should keep about 5 metres back.
Never hover above it or block its path to breathe. Do not chase, touch or feed it.
Follow local guides, avoid bright lights and flash, and leave nests and hatchlings undisturbed.
If a turtle speeds away, changes direction repeatedly or stops feeding, back off. The goal is a wild encounter that leaves its normal behaviour intact. Read Vanuatu’s turtle-interaction guideline.
They are very different sightings, but both make Moso’s diving feel connected to a living coastline. Turtles are credible reef companions; dugongs are documented in the wider Havannah Harbour area and remain unpredictable wild visitors. Come for the reefs and the whole dive experience, then let an encounter be a bonus.
Explore the dugong guide →Questions divers ask
Hawksbills are particularly well documented as nesting turtles on Moso. Green turtles also nest there and appear in the dive photographs on this page. There is no reliable current in-water survey to establish which species divers encounter more often.
October to March is Vanuatu’s main summer nesting period. Historical Moso monitoring sometimes continued into April. A nesting sighting is never guaranteed, and any beach encounter should follow trained local guidance.
A turtle is a genuine possibility around the reefs, but wildlife moves freely. Site choice, conditions and the turtle’s behaviour all affect what you see. No particular sighting can be promised.
Vanuatu’s guidance recommends watching first and keeping at least about three metres away in the water; groups of more than three should stay about five metres back. Approach slowly from the side only if the turtle is relaxed, and leave its route to the surface clear. Never pursue it for a closer image.
Dive the wider Moso story
Explore Moso’s coral gardens, wrecks and nearby offshore terrain with Abyss. The turtles are one wonderful reason to look around slowly and enjoy the journey.
Wildlife encounters and particular dive sites depend on conditions and cannot be guaranteed.
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