Invasive Lionfish and Crowns-of-Thorns May Have Met Their Match

Researchers who are working to eradicate invasive lionfish in the Caribbean and Atlantic waters, and voracious crown-of-thorn starfish on Australia's Great Barrier Reef, may have finally found the solution: killer robots.

The RangerBot is an autonomous drone designed by researchers at the Queensland University of Technology that can detect and destroy crownsof- thorn. "Once the identification is confirmed, RangerBot can instigate a fatal injection into the starfish, but doesn't affect anything else on the reef," says Professor Matthew Dunbabin.

RangerBot is the first robotic design to go into action on a coral reef -- the Australian Institute of Marine Sciences is using it on a trial basis -- when its creators secured $750,000 of funding after winning the Google Impact Challenge in 2016.

In Massachusetts, students at Worcester Polytechnic Institute (WPI) have designed an autonomous underwater robot that can hunt invasive lionfish. Through a combination of floating spears and repetitive learning, the robot can track down and harvest lionfish by itself, without a human operator, and send kills to the surface for collection.

How can it distinguish a lionfish from another innocent fish? The robot has an artificial intelligence platform that allows it to learn, and computer vision software helps the robot identify its prey by giving it images of what fish should not be hunted.

The WPI team will spend the next year working on a navigation system that lets the robot set up and carry out a three-dimensional grid search. The goal is to produce a robot that can be released into the water at a reef and left alone to get on with the job.