With their bold stripes and flowing spines, lionfish are ethereal creatures that resemble delicate underwater flowers. But don’t be fooled—beneath their mesmerizing beauty lies a skilled predator with a deadly defense. From the tropical Indo-Pacific, lionfish are part of the scorpionfish family, and maintain balance in their native reefs. Here, prey know to steer clear, and predators can handle their venomous spines. Outside these waters, however, it’s a different story. Since the 1980s, lionfish have spread like wildfire across the Atlantic, Caribbean, and Mediterranean as invasive species. They reproduce quickly, travel far on ocean currents, and devour over 70 native species, including fish crucial to coral reefs and fisheries. Without natural predators, they’ve thrown ecosystems into chaos. Managing lionfish is an ongoing battle. Scientists have found culling efforts and lionfish derbies work best, and since they’re surprisingly tasty, more restaurants are adding lionfish to the...