Asian Carp Response in the Midwest
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"Asian carp" refers to several species of related fish originating from Asia. Two species of Asian carp—the bighead and silver carp—were imported into the southern United States to keep aquaculture facilities clean and to provide fresh fish for fish markets. Bighead and silver carp escaped into the wild in the 1970s and have been swimming northward ever since, overwhelming the Mississippi and Illinois River systems.
Bighead and silver carp are voracious eaters. This is a problem because the diet of Asian carp overlaps with the diet of native fishes in the Mississippi and Illinois Rivers. Asian carp consume plankton—algae and other microscopic organisms—stripping the aquatic food web of the key source of food for native fish. Averaging 30-40 pounds, some Asian carp can grow to be over 100 pounds. Both bighead and silver carp juveniles can eat between 20 and 120 percent of their body weight each day.
Between 1991 and 2000 the Asian carp population dramatically increased as fish spread throughout the Mississippi and Illinois Rivers. 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. A pound of Asian carp is currently less valuable than a pound of many native fish.
In addition to causing ecological harm, the silver variety of the Asian carp has caused direct harm to people. The silver carp is skittish and easily startled by the sound of a boat motor. The sound causes the fish to leap as high as ten feet out of the water. They have landed in boats, damaged property, and injured people.
An artificial connection – known as the Chicago Area Waterway System – connects the Great Lakes to the Illinois River, which connects to the Mississippi River. The United States Army Corps of Engineers currently maintains an electric barrier to prevent carp from entering the Great Lakes basin. The Corps is also conducting the Great Lakes and Mississippi River Interbasin Study, which is exploring additional options and technologies that could be applied to prevent ANS transfer between the Great Lakes and Mississippi River basins through aquatic pathways.
Biologists, policy makers, and citizens have grown deeply concerned about the prospects of Asian carp entering the Great Lakes through the Chicago Waterway System. If these fish enter the Great Lakes, they may spread throughout the basin due to the natural and man-made connections and the widespread distribution of suitable habitat. While the fish will not find all parts of the Great Lakes to be hospitable, the lakes contain areas where the fish may thrive, reproduce, and cause harm.
The health of the Great Lakes is important to the U.S. economy. The Great Lakes provide over 1.5 million jobs to U.S citizens and over $62 billion in wages. The establishment of Asian carp could decimate commercial and sport fish populations, hurting the Great Lakes' economically valuable commercial, tribal, and sport fisheries.
Recognizing the environmental and economic importance of the Great Lakes, the Asian Carp Regional Coordinating Committee is a federal and state partnership that was formed to help prevent the movement of self-sustaining populations of Asian carp into the Great Lakes.
View maps to see where Asian carp have been found: