Impacts: Their herbivorous feeding can dramatically reduce aquatic vegetation and they can harm water quality by increasing phosphorus levels.
Status: Wild populations of these fish exist in many waters of the United States. No populations are known to be in Minnesota, although individual fish have been caught in state border waters such as the Mississippi River below the Twin Cities and Okamanpeedan Lake on the Minnesota-Iowa border. In 2006, a commercial fisherman caught a large grass carp in the St. Croix River (see photo).
See US map .
Means of spread: They have been stocked in waters of other states, escaped or spread to other waters in flood events, and have spread throughout connected river systems.
Where to look: They have a strong preference for densely vegetated inshore areas of backwaters of large rivers, ponds, and lakes 3 to 10 feet in depth.
Regulatory Classification: It is a prohibited invasive species (DNR), which means import, possession, transport, and introduction into the wild is prohibited.
How can you help?
- Report sightings to the DNR Invasive Species Program and if you catch one bring the fish to your local DNR office
- Don't import or bring these fish into the state