Skip common site navigation and headers
United States Environmental Protection Agency
Great Lakes
   
Recent Additions | Contact Us | Print Version Search:
Begin Hierarchical Links EPA Home > Great Lakes > Invasive Species > Asian Carp
 

Man holding large Asian carp

Photo courtesy of US Fish and Wildlife Service

Asian Carp and the Great Lakes

Asian carp have been found in the Illinois River, which connects the Mississippi River to Lake Michigan. Due to their large size and rapid rate of reproduction, these fish could pose a significant risk to the Great Lakes Ecosystem.

To prevent the carp from entering the Great Lakes, the U.S. Army Corps of Engineers, U.S. EPA, the State of Illinois, the International Joint Commission, the Great Lakes Fishery Commission, and the U.S. Fish and Wildlife Service are working together to install and maintain a permanent electric barrier between the fish and Lake Michigan.

How did Asian carp get so close to the Great Lakes?

Two species of Asian carp -- the bighead and silver -- were imported by catfish farmers in the 1970's to remove algae and suspended matter out of their ponds. During large floods in the early 1990s, many of the catfish farm ponds overflowed their banks, and the Asian carp were released into local waterways in the Mississippi River basin.

The carp have steadily made their way northward up the Mississippi, becoming the most abundant species in some areas of the River. They out-compete native fish, and have caused severe hardship to the people who fish there.

Chicago Area waterways map showing location of carp barrier

Chicago Area waterways map showing location of carp barrier (Illustration courtesy of U.S. Geological Survey)

The Chicago Sanitary and Ship Canal, where the barrier is being constructed, connects the Mississippi River to the Great Lakes via the Illinois River. Recent monitoring shows the carp to be in the Illinois River within 50 miles of Lake Michigan.

What effects might Asian carp have on the Great Lakes?

Asian Carp are a significant threat to the Great Lakes because they are large, extremely prolific, and consume vast amounts of food. They can weigh up to 100 pounds, and can grow to a length of more than four feet. They are well-suited to the climate of the Great Lakes region, which is similar to their native Asian habitats.

Researchers expect that Asian carp would disrupt the food chain that supports the native fish of the Great Lakes. Due to their large size, ravenous appetites, and rapid rate of reproduction, these fish could pose a significant risk to the Great Lakes Ecosystem. Eventually, they could become a dominant species in the Great Lakes.

What are EPA and other agencies doing about it?

Federal and state agencies completed construction of an electrical fish barrier as a demonstration project to study the effectiveness of preventing species migration between the River and the Lake. The U.S. Army Corps of Engineers constructed the temporary electronic dispersal barrier on the Chicago Sanitary and Ship Canal near Romeoville, Illinois, at a cost of approximately $2.2 million. It was activated in April, 2002.

The Illinois Natural History Survey is actively monitoring the effectiveness of the temporary barrier. They have tagged and tracked the movements of 100 common (native) carp near the canal.  To date, only one radio-tagged common carp has breached the barrier, most likely as a result of turbulence caused by a passing barge.  The design of a permanent barrier was modified to address this situation. Simulated tests in a fish hatchery and field monitoring of tagged fish have also shown that the barrier was extremely effective at preventing the movement of fish into Lake Michigan.

Schematic Diagram of Chicago Sanitary and Ship Canal Dispersal Barrier

Schematic Diagram of Chicago Sanitary and Ship Canal Dispersal Barrier (Illustration courtesy of U.S. Army Corps of Engineers)

In late October 2004, construction will begin on a second, more permanent barrier. The new barrier, scheduled to be completed in February 2005, stretches two rows of electrodes across the canal approximately 220 feet apart. The electrodes pulse DC current into the water, causing fish will turn back rather than pass through the electric current. The electric current poses no threat to people.

Changes to the design will provide a stronger, more consistent electric field in the new barrier. A second control house will also be constructed, so that two sets of electrodes -- primary and backup -- can be operated simultaneously. These changes will prevent fish from being swept through by ship turbulence.

The cost of this permanent barrier is $9.1 million.  These funds are 75% federal and 25% non-federal.  The State of Illinois has committed $1.7 for the non-federal share.

Related links

$9.1 million to protect Great Lakes from Asian carp
EPA's October, 2004 press release announcing Federal Funding Available for Enhanced Protection Against Asian Carp

Fisheries Management: Asian Carp Exit EPA disclaimer
Great Lake Fishery Commission Web site about the effects of the invasive species. Includes pictures, video, and many publications on the issue.

EPA's Great Lakes Significant Activities Reports
Information on the dispersal barrier and Asian carp.
May 2002
September-October 2002
December 2002
February 2003

Agencies Take Emergency Action to Defend Against Asian Carp Invasion
EPA's November, 2002, press release announcing the dispersal barrier.

Facts about Asian Carp Exit EPA disclaimer
Facts about the invasive species from the U.S. Geological Survey

Identifying Asian Carp Exit EPA disclaimer
Fact sheet from the U.S. Fish and Wildlife service showing key features and introduction areas.

Invading Asian carp pose unusual threat Exit EPA disclaimer
Article from the U.S. Army Corps of Engineers.

 
 
Begin Site Footer

EPA Home | Privacy and Security Notice | Contact Us