It's a killer robot with a good heart. After years of development and testing, researchers in Australia are preparing to launch an autonomous underwater drone designed to help safeguard the Great Barrier Reef — a mission that includes neutralizing with a lethal injection a coral-eating species of starfish that threatens the reef's health.
Dubbed RangerBot, the briefcase-sized robot has a vision system that lets it navigate underwater, avoid obstacles and identify crown-of-thorns starfish. These creatures, which are covered in venomous spines and can grow almost to the size of a manhole cover, can "devastate large tracts of reef," said Matthew Dunbabin, an engineering and robotics professor at Queensland University of Technology in Brisbane, Australia, and one of the researchers who built the bot.
Dunbabin said the robot, which uses thrusters to move around, is able to identify its quarry with 99.4 percent accuracy. "Once the identification is confirmed, RangerBot can instigate an injection which is fatal for the crown-of-thorns starfish but doesn't affect anything else on the reef," he said in a statement.
But crown-of-thorns starfish are just one threat facing the world's largest coral reef, which stretches more than 1,400 miles off Australia's northeastern coast. Water pollution and overfishing are stressing the reef, and warming ocean temperatures are starving the coral of the algae on which it feeds. That can cause bleaching, which gives the coral a ghostly pallor and makes it more likely to die.
In 2016, huge swaths of the reef experienced a "mass bleaching" event, and some scientists feared the once-vibrant ecosystem was on the brink of collapse. Recent research shows the reef is recovering, but it remains vulnerable.
In addition to killing pesky starfish, RangerBot is designed to help monitor the reef's health by creating 3D maps that can reveal changes in the ecosystem, Dunbabin told NBC News MACH in an email. The drone can stay down much longer than divers can and venture into places too dangerous for humans, such as shark- or crocodile-infested waters.