Snail stink scares starfish to save reef

It's a stink so scary it just might save the reef.

Australian scientists are hoping to recreate the whiff of an oversized sea snail after discovering its scent strikes terror into the hearts of crown-of-thorns starfish.

If researchers can synthesis the smell of the giant triton it could one day be used to help control movements of the starfish, which pose a major threat to reef health.

Footage of lab studies show crown-of-thorns have a violent reaction when exposed to water the snails have been in. They immediately become agitated and try to scuttle away on their stumpy legs.

Dr Scott Cummins, from the University of the Sunshine Coast, says the scent could be a powerful weapon in fighting starfish infestations.

"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," he says.

"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."

The starfish is one of the greatest nature threats to the reef, and has decimated around 40 per cent of coral cover in the last 30 years.

The giant triton, prized for its large shell, has been protected since the 1960s.

It is a natural predator but only eats one starfish per week, meaning breeding enough of the snails to control the crown-of-thorns is unfeasible.