New way to battle reef- killer starfish

A “SIGNIFICANT” breakthrough in the war against crown- of- thorns starfish will improve early detection of the pest.

Australian Institute of Marine Science researchers made the breakthrough.

AIMS senior research leader Dr Sven Uthicke and biochemist Jason Doyle, along with echinoderm expert Dr Miles Lamare from the University of Otago, in New Zealand, developed a costeffective method for detecting DNA of the coral- eating pest.

Dr Uthicke said the method would improve monitoring and early detection of the reef pest, allowing reef managers to contain outbreaks sooner.

“It’s a genetic probe which we had developed to detect seastar larvae in plankton and we have been able to modify the method,” he said.

“We have worked on this for the past three years, and we have been able to adapt this to make it more sensitive to detect adult crown- of- thorns seastar.”

The current method for detecting outbreaks were on- reef field surveys using divers but Dr Uthicke said by the time these methods detected outbreaks, the outbreak was usually well established.

“Standard monitoring techniques only identify about 5 per cent of the pest on reefs, but this new method will allow us to clearly identify whether greater numbers are present,” he said.

During recent field work, using the probe on 11 reefs of the Great Barrier Reef, crownof- thorns starfish DNA was found on those suffering outbreaks.

In contrast, crown- ofthorns starfish DNA was absent from “post- outbreak” reefs after populations collapsed, and from “pre- outbreak” reefs.