A federal study says small fish can be trapped in water currents created by commercial barges and pulled through electric barriers designed to prevent invasive Asian carp from reaching the Great Lakes. The U.S. Fish and Wildlife Service says tests show that fish swimming near barges can remain caught between them for substantial distances.
In one trial, live fish were transported more than nine miles along the Illinois River. They went through a shipping lock and the barriers 37 miles from Lake Michigan at Chicago.
Researchers used golden shiners for the experiments. They're about the size of small Asian carp.
Fish and Wildlife official Charlie Wooley says the results are worrisome but there's still time to reduce the risk of the hungry, aggressive carp slipping past the electric barriers.