Australasian Science: Australia's authority on science since 1938

Snail Scent Scares Starfish

The discovery that the scent of a rare giant sea snail terrifies the crown-of-thorns starfish could help to protect the Great Barrier Reef from its main predator.

“Giant tritons only eat about one crown-of-thorns starfish per week, so breeding enough of them to control big populations is not really feasible,” said Dr Scott Cummins of the University of the Sunshine Coast. “But we now know the giant tritons release this scent that makes the starfish scurry away.

“We hope to chemically synthesise the molecule, then use slow release baits to dispense the scent compound to control the movements of the starfish.

“It won’t kill the starfish but if we can disperse aggregations, particularly during spawning season where they need to be near each other to breed, that might significantly reduce numbers.

“We could also scare them away from particular parts of the reef, and even make them move to areas that are more accessible for divers to poison and remove them in the traditional way.”

Dr Mike Hall of the Australian Institute of Marine Science said that the decline of the giant triton might have contributed to the population explosion in crown-of-thorns starfish, which is responsible for 40% of coral loss on the Reef in the past 30 years.