Mounting urgency as Asian carp threaten the Great Lakes

A congressional hearing this week on Asian carp in the Great Lakes region raises scientific questions and political difficulties. What are the best ways to prevent invasive fish from proliferating, and what would be the economic impact of blocking their passage from the Mississippi River?

Manuel Balce Ceneta/AP
Two Asian carp are displayed Tuesday during a congressional hearing on preventing the induction of the carp, an invasive species, into the Great Lakes. The Asian carp, which can grow up to 100 pounds, were caught in Havana, Ill.

Washington’s focus on snowfall this week was briefly diverted by fish – Asian carp – that threaten to invade and then gobble their way through the Great Lakes ecosystem, likely ruining the pleasure boating and fishing industries of abutting states and Canadian provinces.

Though a looming snow storm caused many official activities in Washington to be cancelled, congressional hearings on the fish threat sailed ahead Tuesday in a nearly empty hearing room – propelled by a mounting sense of urgency and scientific warnings that some Asian carp are even now in Lake Michigan.

The hearings came on the heels of a White House summit Monday to help state and federal stakeholders unite around a plan to fight the threatened invasion by the bighead and silver carp species, which have been working their way north since they escaped from Louisiana catfish farms around 1993. The summit produced a $78.5 million budget and thick “control strategy framework” that identified steps that could be taken.

Critics want specific steps and a timetable

The document was hailed as a unified plan by some and criticized by others for failing to identify specific steps to take – and a specific timetable for implementing them.

Some suggested that electric fish barriers and other measures will meet the threat. Others, though, said the real question is whether to permanently close the channels linking the Mississippi River with Lake Michigan – a step resisted by the shipping industry and others worried about its economic impact.

“All of the actors in this drama have become very good at laying out the different tools they have in their toolbox,” says Thom Cmar, an attorney with the Natural Resources Defense Council in Chicago. “Incremental steps and political posturing [are] still substituting for concrete action. There’s still no clear plan everyone thinks will work and no timetable taking specific steps.”

Varying views on the threat – and what to do about it – were on display at the hearing, the first Congress has held on Asian carp. Front and center: Just how to keep the carp from swimming through the Chicago Area Waterway System’s canals and waterways, which provide a navigation link between Lake Michigan and the Mississippi River and an outlet for storm water and sewage effluent.

Are electrified barriers effective?

The US Army Corps of Engineers since 2002 has built two electrified barriers to prevent the fish from proceeding upstream. It plans to build a third by September along a major link, the Chicago Sanitary and Ship Canal, to prevent carp from swimming through to Lake Michigan.

“Because Asian carp DNA [detection system] has not yet undergone complete scientific independent peer review, the results should be considered ‘preliminary’ at this time,” said Maj. Gen. John Peabody, commander of the Great Lakes Division of the Army Corps. He defended the efficacy of the electric barriers and cast doubt on findings of a Corps-employed scientific team that maintains the carp are being detected miles beyond the barriers – including in Lake Michigan.

“Any assertions that the barrier system is, or has been, ineffective in restricting upstream movement of bighead and silver carp are speculative,” Peabody told Rep. James Oberstar (D) of Minnesota, chairman of the House subcommittee on transportation and infrastructure, and a few other lawmakers.

But minutes later, David Lodge, a Notre Dame University scientist the Corps has hired to detect carp, said his testing system is indeed accurate – and was approved last week by an audit team of specialists from the Environmental Protection Agency.

“What we have discovered, unfortunately … is that both silver and bighead carp are in the waterway north of the electric barrier,” Dr. Lodge testified. “The most troubling result is that silver carp are not only at the doorstep … but in fact appear to be in Lake Michigan – or at least in Calumet Harbor opening to Lake Michigan.”

Trying to prevent a breeding population

This did not mean, he emphasized, that a carp “invasion” has occurred. There is still time to keep a breeding population from developing in the lake, although how much time is impossible to tell, he said.

“We know silver and bighead carp are both very abundant south of the electric barrier,” he said. “Those fish are stacked up … against the electric barrier. If it’s less than 100 percent effective or [if] there’s a flood” that washes them past the barrier, the fish could surge into the lake, Lodge said.

There were other signs, too, of chaffing for action to close the locks and place other physical barriers in the channel to defend the lakes. The US Supreme Court refused to order an immediate closure of Chicago canal locks last month.

But MIchigan last week filed new motions to force action, said Rebecca Humphries of the the Michigan Department of Natural Resources and Environment.

“Is our goal to biologically and physiologically separate these watersheds – or is it not?” she asked.

While applauding efforts to coordinate activity, federal funding, and congressional attention, Ms. Humphries said, “quite frankly we need to do more.” She added: “We do not feel that continuing to operate the lock structure … is a sustainable strategy.”

Barge owners oppose closing canal locks

Testifying for the American Waterways Operators, Del Wilkins, vice president of the Canal Barge Co., said his group supports strong action to stop the carp threat but will not support totally closing the locks.

“We strongly oppose those proposals,” he said in a written statement. “These ideas do not meet the test of our fundamental principle to ensure that appropriate actions balance environmental protection with commercial sustainability.”

Closing the locks would stop barge traffic, replacing the lower emissions and high capacity of barge transportation with truck and rail congestion. Others testified that closing the locks would have minimal impact on the region. Still, Mr. Wilkins said his group would consider more limited opening and closing of the locks, as noted in the White House framework document.

A reduced schedule of lock operation does not satisfy many. As long as a physical connection exists between Lake Michigan and the Mississippi River, carp and other invasive species have opportunities to enter the lakes, Lodge and others said.

Waiting for a flood or power outage that would sweep the fish into the lake would be like playing “Russian roulette with the economy and the environment,” Lodge said. “We’re sitting here talking, and the fish are swimming.”


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