Lionfish Update: The Good and Bad News

At a recent event sponsored by the Reef Environmental Education Foundation (REEF), I learned firsthand why this invasive species is so successful in the Atlantic and Caribbean. As REEF's executive director Lad Akins dissected one, its fitness was revealed. Large fat deposits allow the fish to survive long periods without food. Thirteen venomous spines line its dorsal ridge, plus two pelvic and three anal spines. A sophisticated swim bladder allows it to hover near prey, and long fins can herd it. A maw so large that it can expand to gulp animals its own size, and worst of all, hold huge rafts of eggs. Lionfish spawn every three or four days, releasing two flotillas of up to 40,000 eggs that males quickly fertilize. The egg masses float to the surface, and may have some element binding them together that keeps them from being preyed upon.

This apex predator has no competition in the Atlantic and Caribbean. No fish or crustacean eats it, despite attempts to feed captured lionfish to grouper and snapper. I've seen piscavores gobble down chopped-up lionfish (spines removed) offered by divemasters, but so far, the big fish eaters don't go after living lionfish. Indeed, there is debate about the wisdom of hand-feeding these nasty fish to the big guys. Akins showed an image of one diver who nearly lost a finger to a barracuda who had been conditioned to expect handouts. In Invasive Lionfish: A Guide to Control and Management (available for download at www.REEF.org), James A. Morris cites studies that make clear how problematic this practice is in conditioning fish to go after divers' fingers. Akins noted that success of these invasive animals may owe much to how they got here in the first place, probably as aquarium fishes. That means they survived capture in the Indo-Pacific, transport and probably a pet shop -- a journey that only the strong survive. In addition to their particular genetic robustness, the lionfish here seem to have far fewer parasites than their siblings in home grounds and, of course, no predators. Worst of all, no one knows yet what keeps them in check in the Indo-Pacific.

That's the bad news. The good news is that consistent culling can keep lionfish populations controlled. Every lionfish removed means more native fishes remain. How many is enough? Models vary from 15 to 65 percent removal of adult lionfish as ideal, which is virtually impossible, given the range of the creature. However, sites in the Florida Keys, Bahamas, Cozumel, Caymans, Bermuda, Puerto Rico and Bonaire with active lionfish hunting supported by marine parks and government agencies are succeeding in keeping native biomass sustainable. The other good news is that lionfish meat is delicious. As long as the creatures are not culled from a ciguatera hotspot, the lean white meat makes a mean sushi, fritter or steak. Caymanian bumper stickers tout "Put some sting in your ting" while Bermudians say "Eat 'em to beat 'em." In Bonaire, the Japanese restaurant Osaka offers the Bonairean Caterpillar, a decorative lionfish sushi garnished with avocado. REEF sells The Lionfish Cookbook for home chefs, and according to the New York Times, some restaurants stateside offer invasive species on their menus (Miya in New Haven, for example, has an all-invasive menu of sushi).

Sport divers can help. Many dive shops and organizations sponsor training in safe capture and handling, and lionfish derbies have removed thousands in one day. Find out more at www.reef.org. PADI offers a lionfish hunting certification. Roger Haug of Habitat Bonaire tells me the shop there is starting dedicated lionfish dives, that let divers search for and divemasters capture the creatures.

Mary "Mel" McCombie is a professor at Trinity College in Hartford, CT, and a REEF board member.