Vinegar fatal to crown of thorns starfish

Household vinegar is deadly to the destructive crown of thorns starfish, Australian scientists have discovered, giving hopes of a cheaper means of eradication of the pests.

When conditions are right, the starfish reach plague proportions and devastate large areas of the Great Barrier Reef.

Until now they have been all but unstoppable. But researchers at James Cook University in Townsville have discovered vinegar has a 100% kill rate for the starfish in the lab. The treatment will now be tested at sea.

Lisa Boström-Einarsson, lead author of the JCU report, told The Guardian that further research had to be done to ensure the vinegar did not harm other sea life. “There’s no reason to think it won’t work or it’ll be dangerous, but we have to be sure,” she said.

She said the starfish could not tolerate the acidity of the vinegar. “The acid basically just melts their insides,” she told the ABC. “It is quite dramatic the way they go and within 24 hours there is basically just slime left — it is not pretty.”

But the treatment will be time-consuming, with each individual starfish needing to be injected with vinegar. It is estimated that there are up to 12 million starfish on the reef.

The current eradication technique is to inject the starfish with ox bile which is much harder to come by and more expensive than vinegar.

Boström-Einarsson told the ABC that her new method would not be the saviour of the Great Barrier Reef, but could save individual reefs in the meantime.

“Ideally we would stop the outbreaks from happening or we would control the outbreaks at a population level,” she said. “But at the moment we do not have the tools to do that and we do not have the knowledge to know what causes the outbreaks.

“What we can do is [make] sustained efforts at local reefs and protect them and for that this method will be really effective.”