Invertebrate
Chilean Flat Oyster
Ostrea chilensisAlso known as Bluff Oyster, Dredge Oyster, Chilean Oyster, Ostra Verde
Chilean flat oysters are slow-growing bivalves characterized by their rounded, mud-colored shells with a distinctive greenish hue. They thrive on sandy or gravelly sea floors, where they form dense beds that provide crucial habitat for other marine invertebrates. Unlike many other oysters, they brood their larvae internally before releasing them as highly developed veligers.
BivalveMarineFilter Feeder
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & preyPhytoplankton, Microalgae, Organic detritus
Predators
- Sea stars
- Crabs
- Predatory sea snails
ThreatsOverfishing, habitat destruction from dredging, and parasitic diseases
HabitatsSandy sea floors, muddy estuaries, and coastal bays
Life span8 to 15 years
Classification
- FamilyOstreidae
- SpeciesOstrea chilensis
Range data is not available yet.
Interaction riskHigh
- Low
- Moderate
- High
- Very high
- Why interaction risk is high
- Wild oysters can accumulate lethal biotoxins; check local safety alerts before harvesting.
- Why it is dangerous
- Can accumulate lethal marine biotoxins from harmful algal blooms, causing paralytic shellfish poisoning.
- How to recognize a risky encounter
- Features a flat, rounded, mud-colored shell with a greenish tint, often found clustered on gravelly sea beds.
- What to do
- Never harvest or consume wild oysters without checking local water safety and biotoxin alerts.
Responsible observation
- Observe in tide pools: Look for their flat, irregular shells cemented to rocks in low intertidal zones.
- Check local regulations: Always verify harvesting bans and biotoxin warnings before collecting wild oysters.
Image unavailableCompetitor Predator 
Close Relative Unknown / CC-BY · cc-by
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