Scientists are stepping up the quest for new poisons and other tools that could prevent Asian carp from gaining a foothold in the Great Lakes, Obama administration officials told a congressional panel Thursday.
U.S. Geological Survey experts are looking at short- and long-term methods of reining in the invasive fish amid rising fears they may have eluded electrical barriers on Chicago waterways and are poised to colonize Lake Michigan, said Leon Carl, the agency's Midwest executive.
"The pressure is on our scientists," Carl said, adding that money provided under the Obama administration's $78.5 million carp control plan would help researchers make progress. "I think we're going to do some really exciting research."
Nancy Sutley, head of the White House Council on Environmental Quality, said the studies and other proposals in the government plan have good prospects to succeed -- despite complaints from many in the region that the strategy is inadequate because it doesn't close shipping locks that could open a carp pathway to the lake.
"The Great Lakes face perhaps their most serious threat from invasive species yet in the Asian carp," Sutley said during a Senate Water and Power Subcommittee hearing in Washington, D.C. "We think, however, there's a chance to stop this invasive species before it gets established."
The carp, the largest reaching 100 pounds and 4 feet long, have migrated up the Mississippi and Illinois rivers for decades and infested rivers and canals near Chicago that flow into Lake Michigan.
If a large population spreads across the Great Lakes, the plankton gobblers could unravel the food chain and starve out prey fish on which popular sport varieties such as salmon depend. Silver carp, one of the invasive species, sometimes spring from the water and collide with boaters.
Scientists say even if some carp reach Lake Michigan, as DNA evidence suggests already might have happened, it doesn't necessarily mean all is lost. The key is preventing them from reproducing in large numbers -- a top goal of USGS researchers, Carl said.
They will experiment with methods such as using noisemakers or water cannons to frighten or kill the carp, he said. Longer-term studies will attempt to develop poisons that would kill carp but not other fish, or will seek ways to disrupt carp spawning in tributary rivers.
Another possible measure is using pheromones -- chemicals emitted by animals to attract potential mates -- to lure the fish to places where they could be netted or poisoned.
"A whole (group) of management tools could be coming on in future years as we move forward," Carl said.
Sen. Debbie Stabenow, chairwoman of the subcommittee, repeatedly prodded federal officials to move faster.
"We have a great sense of urgency," the Michigan Democrat said, as the carp could damage the region's $7 billion sport fishing industry and a boating industry valued at $16 billion.
Stabenow's most pointed criticism was directed at the Army Corps of Engineers, which says it needs two years to evaluate severing man-made ties between Lake Michigan the Mississippi River basin.
Environmental groups describe "ecological separation" as the only sure way to stop invasive species from moving between the two watersheds -- a position endorsed this week by the Great Lakes Fishery Commission, an agency representing the eight states adjacent to the lakes.
"It is of great concern to me when we read about a study being completed in 2012," Stabenow said. "We know that these fish are on the move."