Starfish reacts to the smell of a predator
The giant triton snail is one of the very few animals that can eat the extremely voracious, coral-eating crown-of-thorns starfish. Although they generally would only eat one starfish a week, their very presence helps to disperse groups of crown-of-thorns starfish, weakening their ability to breed and multiply on the Great Barrier Reef. Watch this video from the Australian Institute of Marine Science as they show how a crown-of-thorns starfish reacts to the smell of a giant triton.
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Video source: Australian Institute of Marine Science / YouTube.
Biodiversity of the Great Barrier Reef