Great Barrier Reef Being Eaten Alive by Killer Starfish

great barrier reef
The Great Barrier Reef as seen from space. NASA/GSFC/LaRC/JPL, MISR Team

Australia's Great Barrier Reef is being devoured by an outbreak of deadly starfish in yet another setback for the already suffering World Heritage Site.

An increase in the population of crown-of-thorns starfish has spiraled so out of control that instead of helping the famous chain of colorful corals, they are endangering it, the Great Barrier Reef Marine Park Authority announced on Friday, as reported by The New York Times.

Usually the starfish are good for the reef, since they feast on faster-growing coral species, allowing slower-growing species to thrive. But when there are too many of the echinoderms, the coral gets eaten faster than it can reproduce.

The thorny sea stars—which can eat their body width in coral each night—are able to ingest the hard polyps since they have an extrudable stomach that wraps around them. They have been found on 37 sections of the reef offshore north of Brisbane, Australia, according to the Times.

The starfish were responsible for the significant loss of coral cover between 1985 and 2012, when an average of 50 percent of the live polyps disappeared. Since then, protectors of the reef instituted a culling program which has resulted in the removal of more than 600,000 starfish.

Officials have not yet determined the cause of the latest population boom, but scientists hypothesized it could have something to do with currents carrying nutrient-rich water from the deep sea to the reef, creating an ideal breeding ground for larvae growth.

The Great Barrier Reef has been in crisis for years, as the earth's warming temperatures have increased "coral bleaching," a phenomenon in which the polyps are starved of algae, their main food source. New findings published on Thursday showed that the frequency of coral bleaching had increased so dramatically that the reef no longer has time to recover between incidents.

To ward off the slaughterous starfish, park officials deploy two vessels to the reef 250 days a year to cull them, with divers injecting the sea stars with a solution of bile salts or white vinegar.

"Active control of the starfish is the most feasible and scalable action that we can take at this point in time," Fred Nucifora, a spokesman for the Great Barrier Reef Marine Park Authority, told the Times.

While researchers stressed that this is a critical time for the reef as the earth's temperature is rising due to climate change, they say it can still be saved through several approaches that could ensure its survival—most importantly, the reduction of carbon emissions.