Why be concerned? >>

Why be concerned?

While bighead and silver carps are not established in any of the Great Lakes, invasive carp are well-suited to the climate of the Great Lakes region, which is similar to that of their native range in Asia. According to a recent U.S. Geological Survey study, if introduced to the Great Lakes these fish are expected to flourish in the near shore areas and large river tributaries.

While we believe all invasive carp pose a significant threat to the natural ecosystems and recreational opportunities, we are especially concerned about bighead and silver carp.

Reduced fishing opportunities

Researchers predict bighead and silver carp, due to their large size and high reproductive rates, will disrupt the food chain that supports the native fish of the Great Lakes, such as walleye, yellow perch and lake whitefish and may result in reduced recreational and commercial fishing opportunities in the region.

Threat to human health

Silver carp pose a direct threat to human health because they leap high out of the water when disturbed by vibrations like those from boat motors. Boaters can and have been injured when hit by leaping fish weighing up to 40 pounds. Michigan's recreational economy could be affected if people are afraid of injury from silver carp and choose not to go boating in areas where silver carp are present.   

The Illinois-Indiana Sea Grant has published a flyer outlining safety measures for boaters to avoid injury from flying silver carp.  Recommendations include keeping passengers in the middle of the boat, installing netting or shields to deflect fish and avoiding water skiing, tubing or jet skiing in infested waters. 

Video: invasive carp jumping out of the water



Changing ecosystems

In other states where bighead and silver carp have become established, they have changed river and lake ecosystems. In the Chicago Area Waterway System, more than 85% of the fish population is made up of invasive carp.  According to the Asian Carp Regional Coordinating Committee, “between 1994 and 1997, commercial catch of bighead carp in the Mississippi River increased from 5.5 tons to 55 tons.  Today, commercial fishers in the Illinois River regularly catch up to 25,000 pounds of bighead and silver carp per day.”

In early May 2017, a massive silver carp die-off in Kentucky and Barkley lakes in Tennessee left thousands of rotting fish along the shoreline, making fishing and recreation nearly unbearable.