A new test shows Asian carp appear to be moving north on the Mississippi River, which could threaten waters in most of northern Minnesota.
Water samples in the Twin Cities tested positive for genetic material from silver carp, one variety of Asian carp. That indicates the carp likely are in the area, according to the Minnesota Department of Natural Recourses.
Similar DNA traces have been found in the St. Croix River between Minnesota and Wisconsin. The St. Croix joins the Mississippi near Hastings, Minn.
Tim Schlagenhaft, a Mississippi River biologist, said the tests are sensitive and usually indicate fish are in the area. “In other states where DNA testing has resulted in positive samples, the fish have proven very difficult to subsequently capture, and we expect this to the case in the Mississippi River if the fish are in present in low numbers.”
“These eDNA results are like a smoke alarm blaring,” said Superintendent Paul Labovitz of Mississippi National River and Recreation Area in the Twin Cities area. “Until we find the source, we have to assume there is a fire. We have to assume Asian carp are here.”
Experts fear that the invading carp, which eat so much that little food is left for native species, will move up the Mississippi into streams throughout northern Minnesota.
The Legislature and Gov. Mark Dayton earlier this year agreed to spend $16 million to update a dam in the northwestern Twin Cities to prevent carp from going north, but that work is far from being completed.