This fish was above the lock and downstream from the barrier. As to there being only one, well if there is only one, that's a good thing. But I think there were probably more than one, whether they ever find them or not. Bighead and silver carp have a tendency to sink, not float, when killed with rotenone. See below..Also note the fish was 22", not the 22 pounds being reported now.http://www.freep.com/article/2009120...3/?imw=YKiller carp: In hiding or just a big fish tale?Cleanup near Chicago yields just 1 bigheadBY TINA LAMFREE PRESS STAFF WRITERLOCKPORT, Ill. -- As cleanup and Asian carp-searching efforts continued after a massive poisoning in the Chicago Sanitary and Ship Canal on Thursday, officials said they had found a lone Asian carp among the 200,000 pounds of dead fish.The bighead carp, nearly 22 inches long, was found just above the lock and dam at Lockport.That's one of many spots where DNA testing since July has shown the presence of carp.The find is important because it established that the DNA testing is correct. That same testing has shown that there are carp just below an even more critical lock, the O'Brien lock, 7 miles from Lake Michigan.A biologist who tested the poison on carp said Thursday that the fact that more carp weren't showing up dead in the canal wasn't surprising, since his tests showed they would sink to the bottom."There is a chance someone will find one or two," wrote Duane Chapman, a biologist at the U.S. Geological Survey in Missouri.Finding the single carp Thursday will only increase the drumbeat to close the canal off from Lake Michigan. "We're concerned," said Dan Thomas, president of the Great Lakes Sport Fishing Council. The Great Lakes Fishery Commission has pushed for several years to try to get studies done about how the engineering work might be done, said Marc Gaden, spokesman for the Great Lakes Fishery Commission. The canal was built more than 100 years ago to let ships move between the Great Lakes and the Mississippi River basin, and to allow Chicago to flush its waste down the river. Now, it's become a pathway for invasive species to pass back and forth between the bodies of water.