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Lionfish Hunting “Sea Roombas” Can Help Rescue an Ecosystem in Peril

Off the coasts of Bermuda, the invasive red lionfish poses a threat to an ecosystem that thrives in the warm water of the western Atlantic Ocean. This species was introduced to the wild in the 1980s by the people involved in the aquarium trade. Lionfish can grow up to 8 inches long, and they only take a year to reach maturity. Because of this, the lionfish quickly outgrew tanks and were released into the ocean. Unfortunately, the climate of the western Atlantic and Gulf of Mexico is perfect for red lionfish. They eat small reef fish and shellfish, and lots of them, reducing some populations by 65%. Predator species native to the western Atlantic do not prey on lionfish because of their threatening appearance and their venomous spines. Low predation, combined with frequent egg laying and fertilization, allow lionfish populations to soar and wreak havoc on the native ecosystem.

There are many population control methods used to remove lionfish from these waters. Some conventional methods, like hunting and reporting sightings, are beneficial, but scientists have been developing new ways to control the growing lionfish crisis. A new solution gaining popularity is mechanical, developed by Robots in Service of the Environment (RSE), a nonprofit organization that wants to create a new solution to the lionfish crisis. To hunt the hunters, RSE has developed a formidable new enemy: the Guardian, a robot that stuns, captures, and delivers lionfish to the surface for human consumption.  

The Guardian is a remote-controlled robot directed by an operator that can descend to depths of up to 700 feet. Lionfish are slow moving creatures, and they tend not to be frightened easily. The Guardian takes advantage of this and can easily ambush unsuspecting lionfish. Once a lionfish is spotted, the Guardian’s stunning probes send out an electric shock that stuns the fish long enough for it to be captured, but that is not strong enough to harm other fish. The most unique attribute of the Guardian robot, and what gives it a “quirky” appeal, is its vacuum-like technology. One of the founders of RSE, Colin Angle, is a co-founder of iRobot, which manufactures the Roomba, a small automated vacuum cleaner designed for use in residential settings. Angle, his wife, and the other RSE engineers developed the Guardian to suck up the lionfish once they are stunned using the same general principles that household vacuums use. After the fish is stunned, the thruster mechanism generates suction power underwater which captures the lionfish in the holding chamber. The Guardian can then continue “hunting” for more lionfish on its diving session. The holding chamber can hold about ten fish before it needs to resurface for emptying. These robots are powered by batteries, which can last for about an hour before they need to be recharged.

The Guardian robot has many benefits, and chief among them is operational depth. It can travel far deeper than the most experienced divers. Even when divers are able to get below 80 feet, where lionfish population density is greatest, they cannot make a significant dent in lionfish populations in just one dive, since they are limited in the number of fish they are able to carry. Divers also are not ordinarily able to travel very far from the shore, which leaves the deep, open parts of the ocean uncontrolled. These areas are particularly important because they are where lionfish breed, and it is crucial to remove the fish before they lay and fertilize eggs. The Guardian is able to reach these areas that have been inaccessible to divers. 

It is fitting that media coverage has dubbed the Guardian the “Roomba of the sea,” as its engineers are hoping to automate the robot for use as a drone. Instead of bumping into tables and chairs, however, RSE is hoping that the Guardian will be able to effectively and efficiently target lionfish and bring them to the surface to be sold to consumers. RSE wants the Guardian to be a new method of fishing that fishermen, both large and small scale, can own and operate themselves. Fishermen could then sell the lionfish to restaurants or markets where they would not go to waste. RSE is hoping that an increased supply of lionfish will create an increased demand among consumers, creating a market for more lionfish to be consumed. Lionfish are a white meat fish, similar to pollock or snapper, and are considered sweet and delicious. Lionfish meat is gaining more popularity among consumers, and it is even sold at some Whole Foods stores. The largest problem with lionfish consumption today is that the supply is irregular, and RSE hopes that the Guardian will be able to provide a steady, reliable supply of lionfish. 

This goal, while admirable, also presents another challenge— cost. RSE has stated that they want to keep the cost down to around $1,000. Charging a relatively low price may not give RSE a big return on investment, but it makes the Guardian accessible to more fishers who will be more willing to give the robot a try. The more Guardians deployed, the more lionfish that will be cleaned up, which is the ultimate goal of the project. At present, the Guardian robot is still in development, and is not yet available to consumers. It is very close to being ready for the market and planned for release sometime this year. As of yet, there is no official date published.

RSE represents a broader trend of robots being used to solve environmental problems. Robots are able to go into dangerous or out of reach places for humans. Autonomous robots have been used to measure nuclear radiation in the Fukushima nuclear power plant, as well as measuring oil from the Deepwater Horizon oil spill. These robots are able to collect important data and send it back to scientists so they can analyze it. The Guardian is more advanced than these robots in this regard; it does not just quantify the problem at hand, it presents a solution. RSE believes that their Guardian technology is just the beginning of their work. They want to scale the Guardian to hold more lionfish in one dive. They also hope to use technology to solve more environmental problems beyond the lionfish epidemic. 



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