Latest Generation of Lionfish-Hunting Robot Can Find and Zap More Fish Than Ever

It’s always cool to see lionfish while snorkeling or scuba diving. They’re spectacular-looking, and because they’re covered in flamboyant spines, they’re usually secure enough in their invincibility that they’ll mostly just sit there and let you get close to them. Lionfish don’t make for very good oceanic neighbors, though, and in places where they’re an invasive species and have few native predators (like most of the Atlantic coast of the United States), they do their best to eat anything that moves while breeding almost continuously. From a 2010 Oregon State study on a reef in the Bahamas:

A single lionfish per reef reduced young juvenile fish populations by 79 percent in only a five-week period. Many species were affected, including cardinalfish, parrotfish, damselfish, and others. One large lionfish was observed consuming 20 small fish in a 30-minute period.

As horrible as this is, lionfish have the right idea about successfully controlling fish populations—if you want fewer of something, eat it. Lionfish fillets are tasty, and there have been concerted efforts to raise demand for the meat for conservation purposes. The hope is that a robust consumer market will incentivize lionfish hunting, and that humans with spearguns will become the predators that invasive lionfish need.

The trouble with this is where many lionfish hang out and breed, which is too deep for most recreational divers. This is where Robots in Service of the Environment (RSE) comes in. Founded by Colin Angle of iRobot, RSE has been developing remote controlled underwater robots that can efficiently hunt, stun, and capture lionfish at depths of 400 feet for up to 60 minutes at a time, and today they’re introducing their third-generation robot.