Michigan river shows no Asian carp eDNA after positive summer test

Grass carp (Credit: USGS)

Environmental DNA sampling at the end of October found no trace of the invasive Asian carp on the lower Kalamazoo River, according to a release from the Michigan Department of Natural Resources.

The announcement arrives shortly after the DNR and the U.S. Fish and Wildlife Service revealed that summer sampling had produced a positive eDNA result for silver carp in the Kalamazoo. The third and most recent eDNA sampling effort was conducted with the help of local anglers.

The presence of genetic material wouldn’t necessarily indicate a population of invasive carp in the river, as scales, excrement and other DNA-carrying material can brought in on boats or fishing gear, among other sources.

Top image: Grass carp swimming. (Credit: USGS)