Species · GBIF taxon 2259273
Bubble Coral
Plerogyra sinuosaAlso known as Grape Coral, Bladder Coral, Pearl Coral
Bubble corals dominate sheltered reef slopes with their distinctive, water-filled vesicles that swell to the size of grapes under daylight. These specialized structures act as protective cushions and house photosynthetic algae, then deflate at dusk to allow long, venomous tentacles to sweep the night currents for plankton. Their fragile skeletons and slow growth make them vital but sensitive structural pillars of Indo-Pacific coral communities.
MarineReef-BuildingNocturnal Feeder
—observations
—countries
—peak records
Near ThreatenedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNear ThreatenedRed List categories, explained →
Diet & prey
- Zooplankton
- Phytoplankton
- Microscopic organic debris
Predators
- Crown-of-thorns starfish
- Butterflyfish
- Nudibranchs
ThreatsCoral bleaching, ocean acidification, and unsustainable harvesting for the aquarium trade
HabitatsProtected reef slopes, crevices, and turbid shallow waters
Life spanDecades to centuries
Size / weightNot available
Classification
- FamilyPlerogyridae
- SpeciesPlerogyra sinuosa
Range data is not available yet.
Interaction riskVery high
- Low
- Moderate
- High
- Very high
- Why interaction risk is very high
- Possesses potent stinging tentacles that can damage neighboring corals and irritate human skin; avoid touching.
- Why it is dangerous
- Deploys long sweeper tentacles armed with powerful nematocysts (stinging cells) at night to defend territory.
- How to recognize a risky encounter
- Recognizable by its cluster of smooth, grape-sized green or white bubbles during the day.
- What to do
- Never touch the delicate tissue or get too close at night when stinging tentacles are extended.
- What to notice
- Look for pale or completely white bubbles, which indicate the coral has lost its symbiotic algae due to stress.
- Support conservation
- Avoid anchoring boats nearby or kicking up sediment, which smothers the delicate polyps.
Responsible observation
- Observe the shift: Watch how the grape-like vesicles deflate at night to reveal long, translucent feeding tentacles.
- Maintain distance: Keep hands and camera gear away to prevent damaging the fragile, water-filled bubbles.
- Look in crevices: Search for them under overhangs and in sheltered reef areas where water currents are gentle.
Image unavailableReef Companion Reef Companion Close Relative
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