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Crown of Thorns Starfish

Acanthaster planci


Crown of Thorns starfish are natural predators of coral. One individual can eat 13 m2 of coral a year. Their populations have natural blooms and crashes , and are thought to be beneficial for maintaining coral diversity. But over recent years blooms have been huge and have decimated many a reef.


The crown-of-thorns receives its name from venomous thorn-like spines that cover its body.

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Blogie 8 years ago

Yeah, the term "COTS outbreak" has been bandied around for years now. Too bad for the critter. But right now, with the vast destruction it's been causing all around, I don't have much love for it. But, I do agree that more monitoring & studies should be done to fully understand their role in the marine ecosystem.

SamanthaCraven 8 years ago

Yup, there was an 'outbreak' in Malapascua, though I don't like that word - it implies disease and something unnatural when we still don't completely understand why the population of COT blooms from time to time. It did cause a lot of damage though :(

Blogie 8 years ago

Whoa... so many of the in one spot! :(

Spotted by

Biliran, Philippines

Spotted on Dec 13, 2011
Submitted on Dec 15, 2011

Spotted for Mission

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