This Starfish-Killing Robot Could Help Save The Great Barrier Reef

Reef-eating starfish beware

Crown-of-thorns starfish Detection system - COTSBot

Scientists have a new weapon in the fight against starfish bent on devouring the Great Barrier Reef: a killer robot that seeks out and destroys its prey.

Crown-of-Thorns Starfish, or COTS as the researchers behind the robot call them, has plagued the Great Barrier Reef for decades. Since the 1960’s, nutrient runoff from land has made its way into the waters around the reef, causing starfish populations to boom. The COTS is so destructive, scientists estimate that it is single-handedly responsible for almost 40 percent of the coral reef’s loss, Devin Coldewey writes for NBC News.

Enter: the COTSbot.

"Human divers are doing an incredible job of eradicating this starfish from targeted sites but there just aren't enough divers to cover all the COTS hotspots across the Great Barrier Reef," Dr. Matthew Dunbabin, the COTSbot’s creator, says in a statement. "We see the COTSbot as a first responder for ongoing eradication programs - deployed to eliminate the bulk of COTS in any area, with divers following a few days later to hit the remaining COTS.”

The COTSbot is an autonomous submersible armed with a starfish-detection system and a hypodermic needle that can administer a lethal injection to any Crown-of-Thorns starfish it finds. As seen in a demonstration video, the robot can tell the difference between a starfish and anything else on the ocean floor and efficiently deliver a potent poison, saving human divers hours of work, Tom Espiner reports for the BBC.

"The COTSbot becomes a real force multiplier for the eradication process the more of them you deploy,” Dunbabin says. “Imagine how much ground the programs could cover with a fleet of 10 or 100 COTSbots at their disposal, robots that can work day and night and in any weather condition."

Dunbabin first proposed the idea of arming a robot with a COTS-detection system 10 years ago, but had to shelve the project because there wasn’t a practical way to kill the starfish. At the time, the only methods divers had to save the reef was to either remove the starfish or to give each one 20 injections of a poison that would kill the COTS without harming the surrounding ecosystem, Mary Beth Griggs writes for Popular Science. However, last year scientists discovered a way to kill the starfish without harming the fragile coral reef by injecting the starfish with bile. Suddenly, Dunbabin’s concept of a COTS-seeking robot was within reach.

"That was the game changer that opened the doors for a robotic solution to the COTS problem," Dunbabin says. "Combining this with new advances in machine learning meant we could make COTSbot a reality."

Later this month, Dunbabin and his team will take the COTSbot out to the Great Barrier Reef to test its identification system. According to a statement by Queensland University of Technology, every positive ID the robot makes will be reviewed by a human diver before the robot is allowed to inject its target.

"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," Dr. Feras Dayoub, who designed the detection software, says in a statement. "We've now trained the robot using thousands of images of COTS collected on the reef and the system is proving itself incredibly robust at detecting the COTS."

If all goes according to plan, the COTSbot will start hunting starfish on its own by December. 

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