Rare Komodo dugongs underscore need to monitor shallow seagrass meadows

Labuan Bajo — Dugongs recorded in and around Komodo National Park use shallow coastal seagrass habitat, but their rarity and the limited data available mean individual sightings cannot yet be used to gauge local population status or the condition of the meadows they depend on.

Komodo Diving describes dugong encounters in the park as “extremely rare” and notes that they are occasionally seen in shallow bays with extensive seagrass beds, where the animals graze on seagrass in coastal waters between 0 and 10 metres deep.

The site portrays dugongs as shy, elusive marine mammals that spend their lives feeding on seagrass beds in shallow coastal zones, surfacing regularly to breathe and leaving distinctive feeding trails where plants have been cropped and sediments disturbed.

That account helps identify typical encounter settings and depths, but it does not offer a sighting database, population estimates or time-series surveys for Komodo.

What current evidence shows

The 2012 National Review of Dugong and Seagrass: Indonesia, prepared under a GEF/UNEP project, collated literature on dugong distribution, seagrass habitat, threats and conservation initiatives across Indonesia, including reference to dugongs occurring within Komodo National Park.

The review describes seagrass as a shallow-water plant community that stabilizes sediment, reduces wave and current energy, and provides habitat and nursery areas for fish and invertebrates, supporting wider coastal ecosystems and protected species such as dugongs and turtles.

It links dugong distribution closely to food availability, citing studies in which dugong movements, feeding patterns and reproduction are associated with changes in seagrass abundance and nutritional quality.

The review identifies seagrass as the main component of the dugong diet and highlights pioneer species including Halodule and Halophila as particularly important food plants for dugongs in Indonesian waters, with feeding trails and stomach content analyses showing a strong preference for these genera.

Independent guidance for divers echoes this picture, noting that dugongs generally prefer shallow waters and feed mostly at depths of about 1–10 metres in seagrass beds, where they can occasionally be encountered at Komodo dive sites such as Siaba Besar and Tatawa Kecil.

Additional habitat descriptions from conservation organisations report extensive and diverse seagrass meadows in Komodo’s bays and coastal flats, including areas dominated by species such as Thalassia hemprichii, Zostera and other seagrasses off northern Rinca and along Komodo’s mangrove-fringed shores.

Limits of sighting-based information

Dugongs are described as uncommon, highly mobile and difficult to observe, even where suitable shallow seagrass habitat is present.

Local and regional accounts emphasise that sightings around Komodo are genuinely rare and unpredictable, with operators warning that no trip can reliably promise a dugong encounter and that any appearance is treated as a notable but exceptional event.

From a monitoring perspective, an individual observation shows that an animal used a particular area, but it does not reveal how many dugongs live nearby, how frequently they return or whether the seagrass meadow can support them over time.

Scientific and conservation reviews recommend structured monitoring that combines standardized sightings with repeated measurements of seagrass area, species composition, density and condition, in order to track whether habitat is being retained, fragmented or degraded.

Available sources consulted for this article describe Komodo as having extensive seagrass meadows and confirm that dugongs occur in park waters, but they do not present a dedicated, park-wide long-term seagrass monitoring series or a robust population estimate specifically for Komodo.

Implications for visitors and policy

For visitors and dive operators, the current evidence supports treating a dugong encounter in Komodo as a rare and unpredictable event rather than as proof of a stable or abundant local population.

For policymakers and managers, the sources underline that dugong conservation in Komodo is tied to the health of shallow seagrass meadows and that effective assessment depends on systematic habitat and species monitoring rather than opportunistic sightings alone.

Given the ecological role of seagrass in supporting fish, invertebrates and protected species, protecting and studying these meadows in Komodo’s bays and coastal shallows may deliver wider benefits for coastal biodiversity and sustainable tourism beyond the conservation of a rarely seen marine mammal.

Sources

• Komodo Diving – Dugong
• National Review of Dugong and Seagrass: Indonesia
• WCS Indonesia – Dugongs and Dragons
• Komodo National Park World Heritage Datasheet (UNEP-WCMC)
• Diveity – Dugong · Mammals — Dive Guide
• Pinta Liveaboard – Turtles, Dugongs and Mola-Mola in Komodo: What Can You Realistically Expect?
• Literature Review: Distribution and Feeding of Dugongs in Indonesia
• Final Report on Dugong Survey Data and Workshop (CMS Dugong)
• A Systematic Review of the Status, Knowledge, and Research Gaps of Dugongs in Indonesia