Invasive lionfish in the Caribbean Sea are preying on fish species that scientists have not even described yet.
Researchers from the University of Washington and Smithsonian Institution recorded video of a lionfish preying upon a new species of goby off the coast of Curaçao. Their findings, published in the journal PLOS ONE, represent the first observed case of lionfish eating a previously undiscovered fish species.
Lionfish are native to the Middle East and Pacific Ocean, but arrived in the western Atlantic Ocean sometime in the 1980s or 1990s. Lionfish are strikingly beautiful, surrounded by a halo of long, venomous spines. But as an invasive species, they are wreaking havoc on coral reefs in the Atlantic. With few natural predators, they are devastating populations of native fishes.
Lionfish often hunt in the “twilight zone,” an area of ocean between 165 and 985 feet down, below traditional SCUBA diving depths. The zone is so named because only dim light can penetrate that far below the surface.
In the new study, researchers used a submersible named Curasub to record video in the twilight zone off the coasts of Curaçao and Dominica. They captured footage of a school of about 50 orange-striped gobies near a rock wall 384 feet down. The researchers gave this new species the name Palatogobius indendius, or ember goby. They are less than an inch long and tend to hang out in sizable schools, hovering just above the seafloor in deep reef areas.
In the video, a lionfish slowly cruises over the school of gobies, herding them against a rock wall and then suddenly striking at them.
The good news is that the ember goby appears to be locally abundant; the researchers observed many of the fish on submarine trips around the region. However, it is concerning that lionfish are hunting small fish in deep reefs. Almost a third of the fish species along deep reefs have yet to be named, and they could be at risk if lionfish continue to eat their way through native fish populations.
Lionfish are probably in the Caribbean for good, but efforts can be made to mitigate their detrimental effects on native species and ecosystems.
Currently, the most reliable way to control lionfish is through divers with spears and nets. But people cannot safely dive down to the depths that lionfish often frequent. That’s why Robots in Service of the Environment (RSE) designed an underwater robot to vacuum up lionfish. A team of engineers, marine biologists, web developers, and marketers worked together to create a prototype that was demonstrated this spring as part of a sustainability promotion event for the America’s Cup.
Piloted by a Playstation controller, the device runs off a 12-volt battery. A camera mounted on the robot allows the person controlling it to see what the robot sees via a laptop screen. The robot zaps the lionfish, stunning them, and then vacuums them up. It can collect up to ten lionfish before resurfacing.
But what to do with those lionfish? The team hopes to market the robot to commercial fishermen to capture lionfish for people to eat. Although not yet a popular food fish, some conservationists support eating lionfish as a way to reduce their numbers.
At the RSE demonstration, there was also an event where celebrity chefs from across the globe competed to make the best recipe using lionfish.
There is even a cookbook for lionfish recipes. Apparently, they can be cooked in multiple ways, including fried, grilled, and sautéed.
As coral reefs around the world decline due to factors like climate change, ocean acidification, pollution, disease, and overfishing, the deep water reefs could provide refuge for species that can survive in deeper water. But invasive predators such as lionfish threaten native fish and the balance of deep reef ecosystems. It is unclear if eating lionfish will be able to stem the tide of these ravenous invaders, but it’s one strategy gaining the attention of foodies and conservationists alike.