The fact that Asian carp are now in this river and many others, sucking in plankton and growing big and reproducing and waiting to smack a Jet Skier's face, is really not good. Possibly these carp will change large parts of our national watersheds forever. We may be infected with a virus for which there is no cure.

  Among Asian-carp-infested rivers, the Illinois has it worst of all. This river is formed by the junction of the Kankakee and the Des Plaines about fifty miles southwest of downtown Chicago. It runs at a diagonal partway across the state and then turns due south, meeting the Mississippi north of St. Louis. Via the Des Plaines, most of the treated wastewater of Chicago flows south into the Illinois. It's the main industrial river of the state. The fields of corn and soybeans through which it passes are the factory floor, the river is the conveyor. If there's any stretch of this river that doesn't hum and throb—with barges, tugs, grain elevators, power plants, coal depots, refineries—I didn't see it.

  One morning in August I was fishing in the Illinois by the boat-launch ramp in a riverfront park in Havana, Illinois, a town whose full name is pleasant to say. Not much water traffic was passing at this early hour. A light breeze interfered with the deep green reflection of the trees on the far shore, and the echoes of car tires rolling on the brick ramp bounced off some barges parked over there. Fish were rising near the bank in the brown current. I cast to them with a dry fly, but they wouldn't bite. Later, a guy in a sporting goods store explained that these were Asian carp feeding on grain dust from the elevators upstream. In fact, because of the tininess of what they eat, Asian carp are almost impossible to catch with hook and line.

  I quit fishing as the sun rose above the trees and the day became stifling. Two fishermen came to the boat launch from upriver in an eighteen-foot bass boat with a twenty-five-horsepower outboard. They had on camo hats and blue-jean bib overalls. As they were winching their boat onto the trailer, one of them fanned himself with his hat and yelled to me, "Hey, turn down the heat!" I went over and said hello and asked how they had done. They opened their cooler and showed me a beautiful catch of crappies and a medium-sized striped bass. I expressed surprise at their success and said I had heard that the Asian carp had depleted this fishery. Not necessarily, the guys said, adding that there were so many little Asian carp now that the other fish had more prey to feed on. I asked if they thought Asian carp were a serious problem.

  "Oh, hell yes, they're a problem," the smaller of the two guys said. "They jump up and hit you all the time, and they get slime on you, and they shit all over your boat. And bleed —oh, they bleed like no sonsabitches you've ever seen. Yesterday a carp hit Junior in the chest—I thought it would go into his bib—and it left a trail of shit and slime and blood all down the front of him."

  "Hey, look—there's my nephew!" Junior interrupted. A blue-and-white-striped tugboat was going by with a young fellow in jeans and a T-shirt standing in the wheelhouse at the top. "My nephew's the youngest pilot on the river—became a pilot right out of high school," Junior said. He and the other guy waved and the pilot waved back, the happiest man in Illinois. A large American flag fluttered at the tug's stern. All around the boat, from the roiled wake and from the curls of foam at the bow, carp of mint-bright silver were leaping in the sun.

  In the parking lot of the local field station of the Illinois Natural History Survey, just up from the boat launch, two big outboards with twin motors sat dripping on their trailers. After a thorough hosing down, the boats still smelled of disinfectant, and a few fish scales clung to the aluminum structures in their bows. At a desk in the field-station office, Matt O'Hara, a tall, broad-shouldered fish biologist who had just come in from the river, sat and talked with me, while at an adjoining desk a colleague talked to a film crew from an outdoor channel. Another reporter and a film crew from ESPN were expected shortly. During a recent fish survey, Matt O'Hara said, so many fish jumped out of the river at the first jolt of electroshocking that a camera filming from the nearby shore was unable to see the boat. In fact, the visual craziness of the leapingcarp phenomenon, propagated in Internet videos, had been drawing TV crews from all over. Dealing with crews from every major channel, from cable shows, and from Canada, Russia, England, France, and Japan had become part of these biologists' job.

  Their actual and more important job is keeping track of what's in the river. North America's two largest watersheds, the Mississippi and the Great Lakes, connect in one place, Chicago. Boats travel from the Atlantic Ocean into the St. Lawrence Seaway, go through the lakes, turn into the Chicago Sanitary and Ship Canal, continue through the canal into the Des Plaines River, enter the Illinois, and head onward from there to the Mississippi and the Gulf of Mexico. This means, of course, that invasive species can travel the same route in either direction. All of them must pass by the Havana field station's door, and Matt O'Hara and others at the station check the river continually to see if they do. These days the watchers' eyes are on the Asian carp, whose dense population in the Illinois—eight thousand or more silver carp per river mile—exerts a seemingly inexorable pressure northward, toward Chicago and the huge, Asian-carp-free (probably) watershed beyond.

  Like other scientists who grasp the threat, Matt O'Hara becomes severe when he talks about it, though in a quiet and midwestern way. "I don't know if silver carp and bighead carp would necessarily thrive in the Great Lakes," he told me. "Lake Erie is one of the biggest fisheries in the world—the lakes together are a seven- to ten-billion-dollar fishery annually, and most of that catch is from Lake Erie—and it does look as if the carp would do well in that particular lake, and probably trash it. What I'm even more concerned about in the shorter run is the rivers. The Illinois became seriously infested just in the last seven years. A study has identified twenty-two rivers in the Great Lakes system that might be as vulnerable as the Illinois. Some of these are major rivers with important salmon runs, like the Pere Marquette and the Manistee, in Michigan. Asian carp in those rivers could become a disaster really fast.

  "You can eat Asian carp, and they're good. Score the fillets crossways with a sharp knife and cook them in hot oil, and it dissolves a lot of the bones. But given what they do to an ecosystem, I can't say I see any advantage at all with these fish, definitely not if they get in the lakes. They're terrible for the aesthetics, and they certainly make people leery of going out in a boat. Even today, it is still legal to import bighead carp, although silvers are now illegal. And there's another kind of carp, the black carp, that's also in southern catfish ponds and is legal to import and could be an additional disaster if it moved north. Black carp eat snails and mussels and would probably strip our native mollusk and shellfish populations, with all kinds of consequences. That's a danger people should think about, too. We knew fifteen years ago the silvers and the bigheads were going to be a problem, but nothing was done about them. Until recently, nobody paid attention to carp."

  Well, okay—let's eat them. This solution has already occurred to the state of Illinois. Americans in general are not keen on eating carp, so, looking elsewhere, the governor of Illinois recently announced an agreement to sell local carp to the Chinese. Big River Fish Corporation, of Pearl, Illinois, would harvest, package, and ship carp to the Beijing Zhouchen Animal Husbandry Company, while the state would invest $2 million in Big River to improve its facilities and processing capacity. The Chinese had already inspected the product and announced their complete satisfaction with "the wild Asian carp" of Illinois. Zhouchen said it would buy 30 million pounds, and possibly more, by the end of 2011.

  Pearl, Illinois, by the Illinois River in the west-central part of the state, is on Route 100 and has 187 residents. A small post office makes up about a quarter of its downtown. Big River Fish, around a bend on Route 100, announces itself with two hand-painted wooden signs, one facing north and one south, against the trunk of a maple tree. The signs show the profile of a long-whiskered catfish done all in black and shades of gray except for the hypnotic yellow eye. Rick Smith, Big River's
president, was not in his office the morning I drove the eighty-some miles down from Havana. He had just left for the big motorcycle rally in Sturgis, South Dakota, towing his fried-fish cook shack. Rick Smith belongs to the very small number of motorcycle-rally food vendors who also ink multi-million-dollar deals with the Chinese.

  Mike Houston, a Big River employee, was locking up as I arrived. The company would close for about a week until the boss returned, he said. Mike Houston had a red ponytail, gray hair at the temples, blue eyes, a ginger-colored beard, a red Ohio State baseball cap, and a T-shirt with a saying about beer. Accompanying him was another employee, a wiry bald man with tattoos and a walrus mustache. "Yeah, we've already sold our first load of Asian carp to the Chinese," Mike Houston said. "They're also buyin' yellow carp, grass carp, catfish. Thirty million pounds is a lot of fish, but they say it will feed one city. We get the fish in the round—that means whole—and then we gut 'em and power-wash the cavity. That cavity's got to be completely clean before you can ship 'em. The Chinese want the carp with the tails, heads, and scales still on. We flash-freeze 'em in our forty-below-zero freezing chamber and then bag 'em individually and put 'em in big plastic shipping bags that hold twelve or fifteen hundred pounds of fish.

  "We're expanding our operation, but right now we can move a hell of a lot of fish out of here. We can operate year-round, because there's no restrictions and nobody cares how many carp you catch. Guttin' these fish is hard work. Some of the Asian carp go fifty, sixty pounds. Just liftin' 'em is hard. I used to be a chef, I can work a knife, and I've had days when I've gutted and washed twenty thousand pounds of fish. These Asian carp, what they eat, basically, is muck. You'd be surprised, though—their meat is all white meat, and it's good. I've eaten it. People say it's difficult to find Asian carp in China because they're all fished out. I like to think, sellin' silver carp and bighead carp to the Chinese, that we're sendin' their own product back to 'em. And I'll tell you, even with all the fish we move, we ain't makin' a dent in the Asian carp that's out there. There's commercial fishermen in Havana and in Beards-town that we can call up and say we need a hundred thousand pounds of fish right away, and those boys can get a hundred thousand pounds to us in a day or two. And a day or two later they can have a hundred thousand more. No, we ain't makin' a dent."

  The town of Bath, nine miles south of Havana on a long slough of the Illinois, takes a sporting approach to the problem. Every year in August, the Boat Tavern, a waterfront bar in Bath, holds a fishing tournament in which teams of anglers catch silver carp. It's called the Redneck Fishing Tournament; the first was in 2004. Prizes are given for the most fish and the best costumes. This year, 105 boats (at a fifty-dollar entry fee apiece) competed before a crowd of about two thousand in the event's two days. The method of fishing was straightforward: flush the carp from the water with boat engines and snatch them from the air with nets. There was also barbecuing, beer drinking, karaoke singing, games for children and teenagers, bluegrass bands, booths selling T-shirts, and so on. Among the crowd, T-shirt adages were on the order of FRIENDS DON'T LET FRIENDS FISH SOBER AND WHAT HAPPENS IN THE BARN STAYS IN THE BARN.

  From the top of the boat ramp leading to the event, the Redneck Fishing Tournament smelled like ketchup and mud. This was on Saturday afternoon, the event's peak. Spectators milled, media swarmed. At occurrences of even slight interest, a forest of boom mikes converged, while video cameras pointed here and there promiscuously. A notice on a telephone pole announced that just by entering the premises you were granting a production company called Left/Right the permission to use your voice, words, and image in a project temporarily called "Untitled Carp" anywhere on earth or in the universe in perpetuity.

  Tall cottonwoods, ash trees, and maples shaded the shore, which was rutted black mud firmed up in places with heaps of new sand. Crushed blue-and-white Busch beer cans disappeared into the mud, crinkling underfoot. Aluminum johnboats, some camo, some not, lined the riverfront in fleets. Fishing costumes involved headgear: army helmets, football helmets with face guards or antlers or buffalo horns, octopus-tentacle hats, pirate bandannas, Viking helmets with horns and fur, devil hats with upward-pointing horns, a hat like a giant red-and-white fishing bobber, a Burger King crown. Competitors had their faces painted camo colors or gold or red or zebra-striped. Bath, Illinois, was first surveyed by Abraham Lincoln, and on August 16, 1858, while campaigning against Stephen Douglas in the race for the U.S. Senate, Lincoln delivered his famous "House Divided" speech to a large crowd in Bath. He took as his text the New Testament verse "A house divided against itself cannot stand." One hundred and fifty-two years later, the Confederateflag halter tops mingling with the American flags among the tournament crowd would have puzzled him; likewise, the pirate flags.

  The competition took place in heats that lasted two hours. Before each start, boats put off from shore with their engines idling and waited for Betty DeFord, of the Boat Tavern, to give the signal. This honor belonged to her as the inventor and organizer of the tournament. At the air-horn blast, the boats raced off, net-men and -women holding extra-large dip nets at the ready. Soon you could see people plucking fish out of the air. Most of the boats then careered away and out of sight. Two hours later they eased back to the riverbank, many of them heavily loaded. Grinning competitors carried big, heavy-duty plastic barrels of silver carp, a man on each side, to the counting station, where festival officials counted the fish one by one and threw them into the tarpaulin-lined bed of a pickup truck. Among participants and onlookers, a cheerful giddiness prevailed. I had never seen so many fish. It was like an old-time dream of frontier bounty.

  Randy Stockham of Havana won first prize, $1,400. He and his team caught 188 fish. Second prize of $1,100 went to Ron St. Germain of Michigan, with 186. Mike Mamer and his Sushi Slayers, of Washington, Illinois, were third, at 153 fish ($800). Top prizes for costumes were awarded to devils from Greenview, Illinois, and cavemen from Michigan. The tournament also donated $1,500 to help local children suffering from developmental disorders and cancer. A total of 3,239 fish were caught, all of them silver carp. They ended up as fertilizer on Betty DeFord's thirty-acre farm.

  "I'm just a grandmother and a bartender," Betty DeFord said when I called her at the Boat Tavern a week later for a final recap. "I don't even own this bar. I started the Redneck Fishing Tournament because I want to warn other parts of the country about what these carp will do. I remember when this water had no Asian carp, and you could go frog gigging with a flashlight and a trolling motor on a summer night. The way these fish attack, that's impossible now. We just finished our tournament, and the carp are jumping more out there than they ever were. I want everybody to know: these fish need to be gone."

  As you proceed northward toward Chicago on the Illinois, the industrial noise along its banks increases. Turning into the Des Plaines River south of Joliet, you might feel you're in the clanking, racketing final ascent of a roller coaster's highest hill. After Joliet, the machinery of greater Chicago multiplies along the riverbank until, in the municipality of Romeoville, white refinery towers in ranks send white clouds spiraling skyward, and a mesa of coal like a geological feature stretches for a third of a mile, and empty semi-trucks make hollow, drumlike sounds as they cross railroad tracks, and other vehicles beep, backing up. The place is a no man's land. Here the channelized Des Plaines and the Chicago Sanitary and Ship Canal, which have already met up some miles to the south, run parallel, about three hundred yards apart. The water in both of them is the color of old lead.

  Romeoville is where the Army Corps of Engineers and the state of Illinois think they can stop the carp. At two locations on the ship canal, electric barriers zap the water. The canal, a rectilinear rockwall ditch 160 feet wide and about 25 feet deep, passes through Romeoville behind chainlink fences topped with barbed wire and hung with signs: "Danger: Electric Fish Barrier" and "Electric Charge in Water/Do Not Stop, Anchor, or Fish" and "Caution: This water is not suitable for wading, swimming, jet skiin
g, water skiing/tubing, or any body contact." At the fish barriers, steel cables or bars on the bottom of the canal pulse low-voltage direct current. The electric charge—according to the navy, whose divers tested it somehow—is strong enough, under some circumstances, to cause muscle paralysis, inability to breathe, and ventricular fibrillation in human beings.

  What it does to fish is less clear. Entering Chicago, the plucky Asian carp swims into a whole cityful of complications, and it continues to swim single-mindedly while questions of politics, bureaucracy, urban hydrology, and interstate commerce work themselves out. To put it another way: Chicago is a swamp. Various watercourses, only temporarily subdued, thread throughout the metro area. The engineers who caused local rivers to run backward a hundred years ago so as to send Chicago sewage south to the Mississippi rather than into the city's front yard—Lake Michigan—did not have too hard a job, because the underlying swamp could do the same thing itself when in flood. Given enough rainfall, the waters of swampy Chicago become one. The Des Plaines River needs no electric barrier because its Chicago section does not connect to the lake; however, when the Des Plaines floods it sloshes into the ship canal at points above the canal's electric barriers. And the Des Plaines is very likely to have Asian carp.

  Meditating on the complications of the carp's presence in Chicago can disable the brain. Do the electric barriers actually stop all the carp, or are the little ones able to get through? Do stunned fish sometimes wash through in the occasional reverses of flow in the canal? Does the electric charge remain strong and uniform when ships and barges go by? (Probably; instruments in tollbooth-like buildings beside the canal adjust the charge when necessary.) Does the electric field have weak spots where fish can pass? Does a wintertime influx of road salt in the water cause the charge to fluctuate? What about when the current must be turned off for maintenance of the bars or cables? Is the rotenone chemical fish killer that is administered when the current is off effective without fail?