Andrew Stern, PlanetArk 4 Dec 09;
CHICAGO - Authorities scooped up poisoned fish floating to the surface of a Chicago-area waterway on Thursday in an operation designed to keep invasive Asian carp out of the Great Lakes and prevent an ecological disaster.
So far, none of the prolific two species of Asian carp, the Bighead carp and the Silver carp, have turned up in the huge fish kill that began overnight along 6 miles of the Chicago Sanitary and Ship Canal southwest of the city.
Some 200,000 pounds (90 tons) of dead fish are expected to be collected, weighed, inventoried, and dumped in a landfill. Most of the dead fish scooped up so far have been native carp and shad.
Silver carp and the Asian Bighead, which can grow to 5 feet and weigh more than 100 pounds (45 kg), have come to dominate sections of the Mississippi River and its tributaries.
Authorities fear that if the carp swim up to the Great Lakes, the largest fresh-water resource in the world, they could create an "ecological disaster" by consuming the bottom of the food chain and ruining the lakes' $7 billion fishery.
Since 1990s floods allowed the carp to escape into rivers from research facilities and commercial fish ponds in the South, where they were introduced to clean away weeds and other detritus, the carp have multiplied and become a "nuisance species," according to the U.S. Fish and Wildlife Service.
Along some stretches of the Illinois River, the carp make up 95 percent of the biomass and they are considered poor for eating or as a game fish. Silver carp, which leap into the air when disturbed by passing motorboats, have injured boaters.
Two electrical barriers in the canal were erected in 2002 and 2006 to shock any fish, particularly carp, that try to swim up the canal to Lake Michigan. The newer barrier is being switched off to perform maintenance on it.
To give themselves a window to complete the task and keep any carp at bay below the barrier, authorities dumped into the canal more than 2,000 pounds (900 kg) of the natural poison rotenone that prevents fish gills from absorbing oxygen.
The toxin, which is used as a broad-spectrum insecticide and pesticide, kills fish and freshwater snails but does not harm other animals. It dissipates within two days, though authorities planned to introduce a neutralizing agent to speed up the process.
ON LOOKOUT
Notre Dame University scientists recently detected carp DNA on the lake side, which could indicate the carp have already passed the barriers and the effort is too little, and, or too late.
Fishermen have been asked to look out for the invasive carp on the lake side of the barrier.
The DNA discovery led some environmentalists to call for river locks to be shut and ask for permanent separation of the Great Lakes from the Mississippi River watershed.
Michigan Governor Jennifer Granholm has indicated her state might demand locks be closed permanently.
But the shipping industry argued that would be a costly mistake.
The American Waterways Operators, which represents barge operators and other water shippers, said 15 million tons a year of commodities including oil, cement, iron, coal and road salt would be disrupted or halted.
(Editing by Sandra Maler)
Decision soon on closing lock to stop Asian carp
Michael Tarm, Associated Press Yahoo News 5 Dec 09;
CHICAGO – A decision could come within days on whether to temporarily close a vital Chicago area shipping waterway in an increasingly desperate bid to stop the invasive Asian carp from reaching the Great Lakes, an Obama administration adviser said Friday.
Cameron Davis, the Great Lakes adviser to the U.S. Environmental Protection Agency, told The Associated Press that discussions were under way about shutting the O'Brien Lock while crews poison part of the Chicago Sanitary and Ship Canal to kill the giant carp.
"It's going to happen soon," he said about a decision. "We're talking, best guess, within the next two or three days."
Before making a final decision, officials want to finish searching for Asian carp and conduct other tests along the canal to pinpoint where they might be located, Davis said. If officials do choose to close the lock, it would shut down immediately.
Authorities are trying to make sure the voracious carp don't reach Lake Michigan where they could starve out smaller, less aggressive competitors and cause the collapse of the $7 billion-a-year Great Lakes sport and commercial fishing industry.
But closing the lock could also disrupt the movement of millions of tons of iron ore, coal, grain, salts and other goods.
The American Waterways Operators, a trade group representing the tug and barge industry, said Friday that a safety zone set up by the U.S. Coast Guard to search for Asian carp near the O'Brien Lock already made it impassable for commercial vessels.
"De facto it is closed ... They're playing with words on this," said Lynn Muench, a senior vice president for the group. "Our vessels cannot go through to Lake Michigan. We cannot transit." She expected traffic to be restricted for up to eight days.
The closure of the locks, especially for any longer period of time, could result in sharply higher shipping costs because commodities would have to be sent overland by truck or train.
A sense of urgency among environmentalists rose on Thursday after officials said they found a single Asian carp during a fish-kill operation this week in another part of the canal. It was the closest that an actual fish has been found to Lake Michigan.
Last month, officials said they found DNA evidence that the carp may have breached an electrical barrier on the Chicago Sanitary and Ship Canal that is meant to hold back the fish from the lakes. Michigan Gov. Jennifer Granholm and five environmental groups have threatened to sue if the U.S. Army Corps of Engineers to force it to temporarily shut three locks near Chicago over fears the carp will creep into the Great Lakes.
The carp — which can grow to 4 feet long and 100 pounds and are known for leaping out of the water when boats are near — were imported by Southern fish farms in the 1970s but escaped into the Mississippi in large numbers during flooding in the 1990s and have been making their way northward ever since.
The Mississippi and the Great Lakes are connected by a complex, 250-mile network of rivers and canals engineered more than a century ago. It runs from Chicago, on the southern edge of Lake Michigan, to a spot on the Mississippi just north of St. Louis.
In the ongoing battle against the Asian carp, environmental officials began dumping poison Wednesday in a nearly six-mile stretch of the canal to kill off any Asian carp while the electrical barrier was turned off for maintenance. Work was expected to finish on Saturday.
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Associated Press Writer John Flesher in Traverse City, Mich., contributed to this report.
