Native to tropical Indo-Pacific waters, lionfish were introduced to the Atlantic by humans in the 1990s, likely through the exotic pet trade. Now found in reefs from North Carolina to South America, the rapidly reproducing invasive fish have voracious appetites, gobbling up native fish and competing with other species for food resources.
Worse, lionfish have no natural enemies in Atlantic waters, except spear gun-toting humans. Another study, detailed online July 11 in the journal PLOS ONE, found that not even sharks can curb red lionfish populations in Caribbean reefs.
Researchers are trying to figure out what is keeping lionfish in check in the Pacific so that they might stem the Atlantic invasion, which thus far has looked to be unstoppable. Prepared correctly, lionfish are said to make a tasty meal, but one prick from the fish's venomous spine can cause excruciating pain. Lionfish derbies to bring in big catches of the predator have been held in Florida and the Caribbean.
"A lionfish will eat almost any fish smaller than it is," Green said in a statement. "Regarding the large fish we observed in the submersible dives, a real concern is that they could migrate to shallower depths as well and eat many of the fish there. And the control measures we're using at shallower depths - catch them and let people eat them - are not as practical at great depth."