Crown-of-thorns starfish is a large, spiny marine starfish known for its dramatic appearance and its major impact on coral reef ecosystems.
🌊 What it is
The crown-of-thorns starfish is a coral-eating starfish found mainly in the Indo-Pacific region, including the Great Barrier Reef. It gets its name from:
- long venomous spines covering its body
- a circular, crown-like shape
🪸 What it eats
Its main food is live coral polyps.
It:
- climbs onto coral reefs
- everts its stomach onto the coral surface
- digests the coral tissue externally
👉 This feeding method can quickly damage large reef areas.
⚠️ Why it matters (ecological impact)
When population numbers explode (called “outbreaks”), they can:
- destroy large sections of coral reefs
- reduce reef biodiversity
- weaken reef ecosystems that support fish and coastal protection
🧬 Why outbreaks happen
Scientists believe outbreaks are linked to:
- nutrient runoff from agriculture (boosts larval survival)
- reduction of natural predators (like giant triton snails)
- ocean environmental changes
🛡️ Defense and danger
- Covered in venomous spines
- Can cause painful puncture wounds in humans
- Not usually deadly, but injuries require care
🌍 Where it lives
- Tropical coral reefs
- Especially widespread in Australia’s Great Barrier Reef, Pacific Islands, and parts of the Indian Ocean
🧠 Bottom line
The crown-of-thorns starfish is a natural reef species, but when populations surge, it becomes one of the most destructive coral predators in the ocean.
If you want, I can show you how scientists control outbreaks or why coral reefs are so important to the planet.
