Starfish Eats Great Barrier Reef

While some beautiful reefs near Cousteau Fiji have been ravaged by the crown-of-thorns starfish, it has also been eating away at 40 percent of the Cairns section of the Great Barrier Reef, says Australian researcher Udo Engelhardt.

"The current outbreak follows the pattern of two previous outbreaks 15 and 30 years ago," he said. "The apparent synchrony of outbreaks on both the Great Barrier Reef and other reefs throughout the tropics suggest that a large-scale, natural phenomenon could be the trigger for the outbreaks."

The starfish feeds on hard coral, removing all living tissue. Most reefs can handle up to 30 of these starfish per 2.5 acres, but in the most recent outbreak, detected two years ago, some parts of the Great Barrier Reef had up to 1,200 starfish in the same space. It is unknown whether water pollution, overfishing of the starfish's natural predators, or any other human factor triggers the outbreaks.

Injecting the starfish with sodium bisulfate, an environmentally benign chemical, is one control measure, but Engelhardt said that "it would be impossible and a waste of time and money to attempt anything more than small-scale clearing in areas important to tourism."