A commercial fisherman has caught a bighead carp, part of a family of invasive fish, in the St. Croix River.
Bighead carp can out-compete Minnesota's native species and damage the waters they live in. The fish was caught where the St. Croix River joins the Mississippi near Prescott.
The DNR wants help from the National Park Service, the U.S. Army Corps of Engineers, and the U.S. Fish and Wildlife Service, to try to slow the spread of the invasive fish. Locks and dams in the Mississippi are likely barriers, but the DNR says it needs emergency authority to close those locks.
The DNR says a new technology using the ear bone can tell where the carp came from and where it's been.
The last time a bighead carp was found in the St. Croix was in 1996.