The Spikey Crown-of-Thorns Starfish

If you’ve ever seen a starfish up close, you might think they are pretty harmless. How could something that moves so slowly be a danger to humans? But before you go thinking that all starfish are friendly you should meet the crown-of-thorns. This starfish’s sharp venomous spikes are enough to make anyone a little scared.
crown of thorns starfish
Along the coral reefs of the Indo-Pacific Ocean lives the second largest starfish in the world. The crown-of-thorns starfish can grow over a meter across and can have between 7 to 23 arms. The venomous spikes that grow all over the crown-of-thorns’ body can reach up to 5cm long, which sounds awful painful for anyone that might accidentally step on one, ouch!

crown of thorns starfish
Crown-of-thorns starfish population has exploded and can be devastating to coral reefs. There are 6 present in this photo. Photo Credit: Aeysea

Other than humans, these starfish can also be pretty destructive to coral. Crown-of-thorns starfish like to munch on coral polyps, the individual organisms that make up coral and coral reefs. Normally, these starfish live in balance with the coral reef but human impact has dramatically reduced the crown-of-thorns’ natural predators, causing the starfish’s populations to explode. Since they eat the coral faster than it can grow, they can be very harmful for the entire coral reef ecosystem.

bleached coral
Bleached coral killed by crown-of-thorns starfish. Photo Credit: Derekkeats

http://www.arkive.org/crown-of-thorns-starfish/acanthaster-planci/

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