 UTICA, ILL.
-- The 20-foot flat-bottomed johnboat roared up the Illinois River at 30
miles per hour, leaving a roiling brown wake. Suddenly, the water exploded.
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- Twenty pounds of fat, silvery carp shot into the air,
twisting 5 feet above the river's surface before slamming back into the
water.
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- "Watch out -- south of here, they wham right into
the boat or jump in," said Nate Caswell, a U.S. Fish and Wildlife
Service biologist who was driving the boat.
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- Neither happened on this trip, but for the next 15 minutes,
dozens of the ugly, hulking Asian carp performed their odd airborne ritual,
flipping, leaping and skipping across the water.
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- "They freak out at the slightest disturbance, but
nobody knows why," Caswell said. "We want to keep them out of
the Great Lakes if we can, but the fact is they're on the way."
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- It's not just fish that are freaking out these days.
The carp have worked scientists, resource managers and politicians into
a frenzy.
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- Throughout the Great Lakes basin and along the Mississippi
River, officials and researchers are desperately trying to fashion a way
to stop the species' advance.
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- The beasts have made their way upriver for more than
a decade and are now less than 50 miles from Chicago's Lake Michigan lakefront,
held back by an electrified "dam."
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- The carps' voracious eating habits (one fish eats half
its body weight per day) and breeding habits (they're also known as "river
rabbits") could wipe out the base of the Great Lakes' food chain.
Beyond the ecological disaster that they would wreak, the carp could devastate
the lakes' $4.5 billion commercial and sport fisheries.
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- Add to that the grotesque spectacle that has been captured
on videotape several times: Flying carp slamming into boaters, crashing
into boats and flopping wildly in hulls.
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- "I've been hit by them -- everyone in my crew has
been," said Caswell, who has been monitoring the carp for a year.
"One of these days, some boater going 50-60 miles an hour is going
to take a 10-pound carp to the noggin, get knocked out of the boat and
drown."
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- Pam Thiel, who supervises the carp project on the Illinois
River, said such spectacles "seem like slapstick humor, but it's really
black humor when you realize what these carp could do to the Great Lakes."
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- The carp are the most recent poster child in a widespread
battle against invasive, non-native species, which federal officials estimate
cause $137 billion in economic losses nationwide every year. More than
160 of these species have invaded the Great Lakes; a similar number have
moved into the Mississippi River. They include such varying species as
sea lampreys and zebra mussels.
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- But most Minnesotans haven't heard of the Asian carp,
much less been alarmed by their approach.
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- "I've been talking about these things for several
years, but not a whole lot of people are paying a lot of attention,"
said Jay Rendall, exotic species program coordinator for the Minnesota
Department of Natural Resources. "When they do start showing up here,
they will."
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- Four species of Asian carp -- grass, silver, black and
bighead -- were imported into the United States in the 1970s by southern
aquaculture operators who were using them to clean up fish farm waste and
aquatic plants from the bottoms of their ponds. Then, they got out "through
the accidental and intentional, legal and illegal release," said a
Fish and Wildlife Service bulletin.
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- They began moving north, up the Mississippi and its tributaries,
piling up below dams, crowding out other fish species and filling commercial
fishing nets so full that the nets couldn't be lifted.
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- They have become so ubiquitous in the river's lower reaches
that when a fish kill of undetermined origin occurred four years ago on
the Mississippi in Illinois, biologists discovered that 97 percent of the
fish were Asian carp.
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- "On the ecological side, they just outcompete native
fish," Rendall said. "They filter up so much zooplankton, there's
not going to be much left for the native species to eat."
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- Confronting a specter of a devastated Great Lakes fishery
that would become, in effect, a vast carp farm, governments of both the
United States and Canada have poured more than $1 million into heading
off disaster.
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- Last month, Chicago Mayor Richard M. Daley convened the
Aquatic Invasive Species Summit, a gathering of nearly 70 scientists, engineers
and biologists who are trying to get carp under control. "The longer
you put off solving a problem, the more it costs you in the long run,"
Daley said. "An aggressive solution to a problem is always cheaper
than repairing the damage later."
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- Dennis L. Schornack, the chairman of the U.S. section
of the International Joint Commission, which manages water bodies along
the U.S.-Canadian border, called invasive species "the No. 1 threat
to both the ecology and the economy of the Great Lakes."
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- Thiel said the issue has received high-profile support
"because this could cost big bucks, and people like Mayor Daley realize
that."
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- The Great Lakes' last line of defense against the carp
is an electrified "dam" that has been installed in the Chicago
Sanitary and Ship Canal about 25 miles from Lake Michigan. The canal was
originally the Chicago River, which dumped raw sewage into the lake. It
was re-engineered in 1900 to flow the opposite way, connecting it to the
Illinois River's drainage.
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- That inadvertently gave the carp and other, more benign,
species a portal into the Great Lakes.
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- "Connecting the two had major implications for the
whole mid-continent that no one could forsee," Thiel said.
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- Since the electric barrier was switched on in April 2002,
it has apparently done its job of repelling carp. But it has an expected
lifetime of only three years, and federal officials are scrambling to beef
up its reliability and build a permanent replacement.
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- Although carp have been found within a few miles of the
barrier, the main advance remains farther away, according to the results
of an annual survey of the Illinois River that was conducted earlier this
month.
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- "We didn't get them any closer than 21 miles from
the barrier," said Thiel, who supervised what was dubbed a carp corral.
"But they were more numerous where we were netting them."
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- A 14-boat armada carrying nearly 50 fishery biologists
criss-crossed about 100 miles of the Illinois River for a week, repeatedly
setting gillnets and recording their unwanted catches.
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- Thiel spent one morning with Caswell and fellow biologist
Eric Leis on a stretch of the river centered on Starved Rock State Park.
Although the biologists had had a 15-carp haul the day before, pickings
were slim.
- "Well, that bites," Caswell said as he pulled
in a nearly empty net.
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- "I guess we solved the problem -- we've caught all
of them," Leis said.
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- By morning's end, they had hauled in only four carp,
which were tossed into an oversized cooler.
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- After being tested for diseases and pathogens, the fish
would be "bled out and deep-sixed," Caswell said. "They
stink so bad there's not a Dumpster around here that would take them."
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- Marveling at their bloated ugliness, he described the
fish as "like salmon from Bizarro World. In a postapocalyptic world,
all you'll have left is cockroaches -- and carp."
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- Bob von Sternberg is at vonste@startribune.com.
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