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Invasion of the Snakeheads

The voracious "Frankenfish" has turned up in the Potomac River, Lake Michigan and a California lake, sparking fears of an ecological Armageddon

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Besides Crofton and the Potomac, the fish have popped up in several other places in the United States. In 1997, one was caught in a Southern California lake. A couple more appeared in Florida waters in 2000. In Massachusetts, one was caught in 2001 and a second in 2004. And in July 2004, an angler caught two in a lake in a Philadelphia park. Like the Crofton fish, the Philadelphia ones had settled in and started reproducing. But unlike the Crofton fish, they had access to a river—the Schuylkill, which feeds into the Delaware. Moreover, tidal gates that normally keep fish in the park had been stuck open for two years. Philadelphia fisheries managers decided that poisoning or draining the park’s interconnected ponds would cause more harm to resident fish than the snakeheads would, and have resigned themselves to snakeheads becoming a new member of the park’s ecosystem. The most recent surprise appearance was this past October when a northern snakehead was pulled out of Lake Michigan. The catch has raised fears that the voracious predator might take over the Great Lakes.

The northern snakehead, which is native to parts of China, far eastern Russia and the Korean peninsula, may seem plug-ugly to the undiscerning eye—it has big, pointy teeth and, given its particularly heavy mucus covering, a slime problem. It can grow up to five feet long. Like its reptilian namesake, it’s long and slender and can sport blotchy snakelike patterns on its skin. Unlike most fish, the northern snakehead has little sacs above its gills that function almost like lungs; the fish can surface and suck air into the sacs, then draw oxygen from the stored air as it swims. The air sacs are handy for surviving in waters that are low in oxygen, and even allow the fish to survive out of water for a couple of days, as long as it doesn’t dry out. A female lays thousands of eggs at a time, and both parents guard their offspring in a large nest they make in a clearing of aquatic plants.

Northern snakeheads are a popular food in their native range; they’re said to be good eating, particularly in watercress soup, if a bit bony. They’re fished commercially and raised in fish farms in Asia. They’ve also been sold live in markets in the United States. The Crofton snakeheads were eventually traced to a Maryland man who’d bought two of the fish in New York City for his sister to eat. When she demurred, he kept them in his aquarium and later released them. The U.S. Fish and Wildlife Service soon banned the importation and interstate transport of snakeheads, a plan that had already been in the works precisely because of fears that some snakehead species could thrive in parks, rivers and lakes if they got loose. The ban made it illegal to import all live snakehead species, including the colorful tropical species that populate the odd aquarium. Virginia has outlawed the possession of all snakeheads.

But the bans haven’t stopped everyone. A Los Angeles grocer was arrested this past May for allegedly smuggling live northern snakeheads into the country from Korea and selling them in his store; he pleaded guilty to importing an injurious species. U.S. fans of snakehead soup and other delicacies, however, may still legally obtain killed, frozen snakeheads, which are available in many of the Asian markets that once sold them live.

One day this past April, an angler caught a feisty northern snakehead in Pine Lake, in Wheaton, Maryland, outside Washington, D.C. Local officials drained the lake but found no more snakeheads. Then, like an ecological game of Whac-a-Mole, another northern snakehead reared its toothy head the very next week when a professional bass fisherman pulled a 12 1/2-incher from Little Hunting Creek, a Potomac tributary in Virginia about 15 miles south of the nation’s capital. Biologists tried using nets to capture snakeheads in the river, but eventually decided that a better way would be to let anglers go at the fish with plain old hooks and lines—which led to one of the odder fishing tournaments in recent memory.

On an overcast Friday morning in July, I joined a few dozen anglers at Columbia Island Marina in Arlington, Virginia, across a narrow channel from the Pentagon. The 2004 Snakehead Roundup was about to get under way. The roundup was sponsored by the Marina Operators Association of America to remind boat owners to take care not to transport unwanted species from one place to another—as hitchhikers on their boats or trailers, for example—and to let them know what northern snakeheads look like. Although 16 adult snakeheads had been caught in the Potomac by that time, no one knew whether they’d been born there or whether someone had just tossed them in—or even how common they were.

I tagged along in a 19-foot white-and-blue ski boat with three managers from a family-owned company whose boss didn’t seem to mind that the information technology division was running itself that day. “We’re conducting an offsite meeting,” software designer Brian Turnbull explained. Turnbull’s father-in-law, who is Vietnamese, asked him to bring a snakehead home. “He says if you catch one, you don’t have to hand it over to the state. It’s a delicacy.” Fortunately, Turnbull wasn’t required to choose between duty to family or to society because he didn’t catch a snakehead. Neither did anyone else on the boat, and neither, we found out when we later pulled up at the marina, did anyone else in the roundup.

A few weeks later, John Odenkirk, a biologist from the Virginia Department of Game and Inland Fisheries, seemed to be imitating the sheriff in Snakehead Terror, who kills his murderous lakeful of snakeheads by electrocuting them with a downed power line. Odenkirk, driving an aluminum boat through Dogue Creek, a Potomac tributary, was “electrofishing,” which involved running about 1,000 volts through a boom that protruded from the bow and trailed wires in the water like tentacles. “High voltage . . . The next best thing to explosives,” read the small print on the back of Odenkirk’s green “Snakehead Task Force” T-shirt, which he designed to sell to colleagues for $12 apiece.

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