The first of an estimated 200,000 pounds of dead, poisoned fish floated to the surface Thursday along a 6-mile stretch of the Chicago Sanitary and Ship Canal near Romeoville.
Hundreds of workers braved the chilly winter temperatures to pluck the fish – mostly gizzard shad and common carp – from the water and send them to a nearby landfill.
The operation is a dramatic and expensive attempt by the Illinois Department of Natural Resources and nearly a score of partners, including other states and Canada, to keep voracious Asian carp from invading Lake Michigan while the canal’s electronic fish barrier is turned off for maintenance.
On Wednesday, the crew rescued desirable sport fish from the canal. Overnight they then applied 2,200 gallons of rotenone, a liquid toxin that biologists have used for decades to control invasive fish in Midwestern waters. Although rotenone is deadly for fish, it poses minimal risk to humans or other wildlife, according to the natural resources department.
“It’s time to man the barricades,” said John Rogner, assistant director of the department. “We’ve simply got to protect the Great Lakes at all costs.”
The U.S. Army Corps of Engineers operates the system of electric fish barriers in the canal. The Army Corps has spent $15 million in state and federal dollars since the first barrier was installed in 2002. This week’s operation alone is expected to cost between $1 million and $2 million.
But some fish may have already breached or bypassed the barrier, according to the University of Notre Dame based on DNA evidence found up river from the barrier two weeks ago.
“We are confident that, if there are any number of carp above the barrier, they are in very low numbers,” Rogner said, explaining that a handful of fish in the lake would not pose a serious threat. “Our goal and our expectation is to be able to keep them from moving through the Sanitary and Ship Canal, at least in numbers that would allow them to establish a population.”
Michigan Gov. Jennifer Granholm and five environmental groups threatened on Wednesday to sue the Army Corps to force it to temporarily shut down three shipping locks near Chicago – a move that would prove a deep blow to regional shipping interests.
Although no steps have been taken to lock the dams yet, Col. Vincent Quarles, commander of the corps’ Chicago district, left the door open.
“All options are on the table for keeping Asian carp from migrating into the Great Lakes,” Quarles said.
The Asian carp threat
The Asian carp's size, voracious appetite and tendency to jump out of the water when bothered by a passing motor boat have made the species a scourge of biologists, fishermen, environmentalists and government administrators.
The largest carp ever caught in the U.S. was a bighead that weighed in at just under 100 pounds. Most carp don’t reach nearly that size – the average bighead in the Missouri River in 2005 weighed slightly less than 11 pounds and stretched about two and a half feet in length. Such fish can still cause significant damage to both equipment and people when they jump, though.
“I’ve been hit by one,” said Jim Robinett, vice president of animal legislation and regulation at Chicago’s Shedd Aquarium who has participated in carp corral monitoring programs. “I can tell you, it really hurts.”
The fish have broken everything from ship radios to people’s noses and collar bones since they began their northward journey up the Mississippi River in the early 1990s. Experts generally agree that Asian carp were washed from a fish farm during a flood event.
Aside from physical threat, fears focus largely on the fact that carp are filter feeders. Like all fish, they breathe through their gills. But Asian carp feed on the plankton they breathe in, rather than letting it float back out like most fish and some carp can eat up to 40 percent of their body weight a day. Plankton makes up the base of the food chain. Without it small fish disappear and larger fish soon starve for want of prey.
“There are parts of the river where they make 90 to 95 percent of the river,” Robinett said. “If these animals get out there… it could be devastating. It could create essentially an ecological wasteland.”
That threat has the region’s fishing interests up in arms.
“We’ve seen dozens of invasives make their way into the Great Lakes,” said Dan Thomas, president of the Great Lakes Sport Fishing Council and a vocal supporter of the fish fence. “We’ve lost every time.”
The U.S. Environmental Protection Agency counts more than 180 invasive species that have established themselves in the Great Lakes over the past two centuries, including plants, algae and fish.For instance, the round goby, a bottom-dwelling fish from the Caspian Sea, has out-competed native species. There’s the sea lamprey, an eel-like fish that suctions itself onto prey using its mouth and sucks out their blood and bodily fluids. And most notoriously, there’s the zebra mussel, which had so thoroughly covered the floor of Lake Michigan by the early 1990s that towns spent millions of dollars on systems to remove mussels from municipal water in-take pipes.
Zebra mussels “would rather grow one on top of another on our intake pipe,” said Nabil Quafisheh, assistant superintendent to the Wilmette water plant, “they would grow so thick that we worried about capacity, so we installed a zebra mussel control system.”
Zebra mussels, like carp, filter the water. In the Great Lakes, the influx of zebra mussels lead to much clearer water, allowing sunlight to reach new depths where algae began to grow dramatically. Now, algae in the Great Lakes is home to e. coli and to viral hemorrhagic septicemia, a deadly fish virus nicknamed “fish Ebola,” according to the EPA.
Government administrators and environmentalists frequently reference the zebra mussels’ story in explaining why even extreme measures to stop invasive species are necessary.
Asian carp, too, pose algae problems. Duane Chapman, a fish biologist at the U.S. Geological Survey, said Asian carp could cause an influx in a species of blue-green algae called microcystis that releases toxins harmful to humans.
“Other things don’t like to eat it, but Asian carp do,” Chapman said. “And it can pick up nutrients while in the carp’s gut and can pass out the other end raring to go.”
He said a rise in microcystis could pose a hazard to drinking water supplies tapped from the Great Lakes and create new challenges for water treatment.
Restoring the Great Lakes
“As the Great Lakes go, so goes national policy with respect to water,” said EPA Administrator Lisa Jackson just one month after taking office last winter.
President Obama made good on his administration’s commitment to the Great Lakes when he signed a spending bill that included $475 million for the Great Lakes Restoration Initiative two weeks ago. The EPA-led project aims to tackle the region’s biggest problems such as pollution and contaminants, and includes more than $60 million to deal with invasive species.
A large chunk of that $60 million will go toward addressing one of the primary ways non-native species make their entry: commercial ships.
Before a voyage, cargo ships take on water, called ballast water, for stability. When they arrive at their destination they release the water – and all of the organisms living in it.
“You can’t fully address invasive species without addressing ballast water,” said Thom Cmar, an attorney with the National Resources Defense Council. “Sixty-five percent of invasive species come in through ballast water.”
The EPA currently requires that ships exchange their ballast water at sea with salt water, a procedure that is dangerous. And researchers estimate it's only about 85 percent effective in killing organisms living in the ship’s ballast tanks.
Now, the U.S. Coast Guard is writing new rules that would limit the actual number of organisms entering the ship.
“Some states like New York and Michigan have their own standards,” said Commander Timothy Cummins, in charge of the Coast Guard rulemaking. “Our national goal has been to set a concentration-based standard.”
But even with stricter ballast water standards in the pipeline and new federal dollars to fight invasives, environmental groups are increasingly calling for a fundamental change in the region’s infrastructure to stem the tide of invasive species.
“The Great Lakes are really a closed system, but they’ve been pierced in various ways,” said Cmar, whose group calls for a permanent separation of the Great Lakes from the Mississippi River watershed. “Ultimately, closing these artificial connections is the only way to stop the spread of invasive species.”
“It’s not a hair-brained idea,” said Elizabeth Murphy a Great Lakes program manager at the EPA. “It would have a serious cost for shipping interests, but this action happening in the Chicago Sanitary and Ship Canal has brought a lot of attention to invasive species and the harm they could do to the Great Lakes.”