— While scientists have been battling to keep a ravenous, invasive fish species out of the Great Lakes, some worry that spring floods along the Mississippi River may be spreading the Asian carp downstream.
Duane Chapman, a U.S. Geological Survey biologist and Asian carp expert, says the fish are likely to show up in places where Mississippi floodwaters intruded. They can weigh up to 100 pounds grow 4 feet long and live for 25 years.
They could be crowding out food sources of native species for decades. “I think there is a very serious issue here,” said Chapman. “We may now be finding them in lakes, ponds, bayous, anywhere the river water went. Those things will be full of carp now.”
Asian carp is a term applied to several related species of carp that were brought to the United States in the 1970s to control algae in catfish farms in the South. Floods washed them into the Mississippi River in the 1980s.
Since their escape into the wild, the carp have established themselves in the Mississippi and Missouri river basins. They endanger native fish by greedily eating aquatic vegetation and robbing local species of their food supply.
The battle to keep them out of the Great Lakes includes the use of underwater cameras and sonar to monitor the effectiveness of the Army Corps of Engineers’ electronic barriers.
The Mississippi’s spring floods inundated an estimated 6.5 million acres along a 1,000-mile stretch of winding river from Cape Girardeau, Mo., to the Mississippi’s mouth in Louisiana, said corps spokesman Bob Anderson. Top 10 Evil Animals: Asian Carp
In Mississippi, ponds holding farmed catfish have taken a heavy toll from backwater flooding. The industry says it may take a year to scrub out the ponds and remove much that was left behind, including Asian carp. They also will have to restock because their crop either swam away in the flood or died because of muck and foul water entering the ponds.
The fish thrive in fast-moving water, said Ruben Keller, a lecturer in environment studies at the University of Chicago who has worked extensively on Asian carp with the National Invasive Species Council. “They spawn in high water events like the flood,” Keller said. “This will produce many more carp.”
The lakes are brackish — a mix of fresh and salt water.
Most freshwater species cannot survive in a salty environment. But the carp can. “Asian carp unfortunately are the exception that can do fairly well in high-salinity water,” Chapman said.
How far the fish may spread because of the flood won’t be known for some time, he said. “At this point we have to wait until after the flood dissipates before we can evaluate and see how bad it is.”
