Matt Dunbabin (left) and Feras Dayoub with the COTSbot robot which is designed to search for and kill Crown of Thorns Starfish. Queensland University of Technology / Erika Fish

The Great Barrier Reef is under attack from hungry hordes of Crown-of-Thorns starfish, but Australia has an answer: killer robots trained to recognize the many-armed menace — and administer a lethal injection.

It sounds like the plot to a bad sci-fi movie, but it's very real. These starfish have multiplied in recent years, and are estimated to have caused 40 percent of the reef's coral loss. Divers regularly do sweeps for COTS, as they're called, but they don't call it the Great Barrier Reef for nothing — there's a lot of space to cover.

Queensland University of Technology's Matthew Dunbabin and Feras Dayoub have created a submersible robot that patrols just a foot or two off the sea or coral floor, using a specially-trained computer vision program to watch for COTS. When it spots one, it will extend a syringe and give the animal a dose of bile salts, a poison that happens to be especially effective against the starfish.

The robot also will try to minimize false positives: "If the robot is unsure that something is actually a COTS, it takes a photo of the object to be later verified by a human, and that human feedback is incorporated into the robot's memory bank," explained Dayoub in QUT's news release. You can see more pictures of the robot and what it sees when it's hunting at the project's Flickr page.

"We see the COTSbot as a first responder for ongoing eradication programs," said Dunbabin, "Deployed to eliminate the bulk of COTS in any area, with divers following a few days later to hit the remaining COTS."

Queensland University of Technology

At least, that's the plan. For now, the COTSbot is still in prototype form — functional, but untested. It will soon take to the seas for some initial runs, during which every COTS identification must be confirmed by a human before the injection takes place. But with time, fleets of COTSbots could scan the corals, allowing the troubled ecosystem time to recover. Let's just hope the robots don't decide humans are the next threat.