Protecting Northern Michigan's ​Water Resources

Detailed Timeline for Invasive Carp in the United States

1900: The Chicago Sanitary & Shipping Canal was completed creating a permanent connection between Lake Michigan and the Mississippi River Basins. The canal system was originally constructed to permit Chicago to dispose of its wastewater without allowing it to enter Lake Michigan, its source of drinking water. 

Before and After of the Chicago Sanitary & Shipping Canal
Credit: United States Army Corps of Engineers

1963: The U.S. Fish and Wildlife Service imports grass carp from Eastern Asia to Arkansas for federal research on controlling aquatic vegetation in aquaculture ponds. 

1966: First believed escape of invasive carp into U.S. waters, in Arkansas. 

1970: State of Arkansas begins stocking grass carp in weed-choked waters throughout the state. 

1972: Bighead carp are first brought into the US by a fish farmer in Arkansas to improve water quality and fish production in aquaculture. 

1973: Silver carp are introduced into the US for phytoplankton control in culture ponds and as fish food. 

1973: An Arkansas fish farmer who ordered grass carp unintentionally receives the nation’s first shipment of black carp. 

1974: The Arkansas Fish and Game Commission report extensive stocking in more than 100 public or semi-public lakes with over 50,000 acres stocked with more than 380,000 grass carp. 

1976: Silver carp, stocked in sewage ponds, escape into wild during flood. 

1976: First wild sighting of invasive carp in Arkansas. 

1980: The first report of silver carp swimming in the wild. 

1981: The first record of a Bighead carp caught in natural waters when an individual was caught on the Ohio River below Smithland Dam, Kentucky. 

1982: Carp considered “established” in the wild in Arkansas. 

Early 1990s: Heavy flooding allowed more carp to escape from fish farms in the Mississippi and they have since migrated into the Missouri and Illinois rivers. 

1994: The first record of escapement or release to the wild of black carp occurred in Missouri. Thirty or more black carp escaped into the Osage River in Missouri when high water flooded holding ponds at a private aquaculture facility near Lake of the Ozarks. 

1996: Army Corps of Engineers directed to build demonstration electric barrier for aquatic nuisance control. 

2002: Barrier I, a demonstration electric barrier in the Chicago Sanitary and Ship Canal 25 miles from Chicago, comes online. The electric barrier on the canal is designed to prevent the spread of aquatic nuisance species. 

Late 2002: Biologists find invasive carp 21 miles downstream of the experimental fish barrier, about 50 miles from the Lake Michigan 

2007: Congress, through the Water Resources Development Act (WRDA,) directs the Army Corps of Engineers to study factors that could reduce effectiveness of electrical barriers, including areas of potential bypass via flooded areas and to conduct a study to prevent the transfer of aquatic invasive species between the Great Lakes and the Mississippi River Basins. The US Fish and Wildlife Service add silver, large scale silver, and black carp to the list of injurious wildlife. The importation and interstate transportation of certain listed wildlife is prohibited, with exceptions.

July 2009: DNA monitoring tested positive for the presence of invasive carp beyond the barrier, 6 miles from Lake Michigan.


December 2009: The electric barrier is shut down in order to conduct maintenance. To prevent invasive invasive carp from entering the lakes while the barrier is not turned on, fisheries managers treated a 5.7 mile portion of the canal with poison, rotenone, resulting in a large scale fish kill. One invasive carp was found among the dead fish that was collected in the canal. Michigan Attorney General filed suit in the U.S. Supreme Court on behalf of the State of Michigan against the State of Illinois for allowing invasive carp to potentially invade the Great Lakes through the Chicago Canal and other managed waterways. 

January 2010: The Supreme Court refused to order emergency measures sought by the State of Michigan to stop the migration of the invasive carp toward Lake Michigan. Hours later, the Corps of Engineers announces it has found invasive carp DNA in waters connected to Lake Michigan for the first time. 

February 2010: President Obama pledges $78 million to prevent invasive​ carp in the Mississippi River and Chicago Waterway System from invading the Great Lakes. 

April 2010: The U.S. Supreme Court refuses to hear a request to permanently separate the Great Lakes from the Mississippi River to prevent the movement of invasive carp and other harmful aquatic invasive species between the two basins, effectively ending any hope for Michigan and the other Great Lakes states to get the invasive carp case before the Supreme Court. 

May 2010: A second round of poisoning was conducted into two miles of the Little Calumet River below the O’Brien lock and dam. The purpose was to determine whether invasive carp might exist in that location where positive eDNA samples have been taken. No invasive carp were found.

June 2010: An invasive bighead carp was caught in Lake Calumet, 6 miles away from Lake Michigan. This is the first physical specimen that has been found in the Chicago Area Waterway System above the U.S. Army Corps of Engineer’s Electric Barrier System. A stone blockage was placed in the Illinois and Michigan (I&M) Canal to prevent invasive​ carp being swept from the I&M Canal into the Chicago Sanitary and Ship Canal during heavy rains.

July 2010: invasive carp are found in Indiana’s Wabash River, a few miles from where the Wabash often floods and flows into the Maumee River, a major tributary of Lake Erie. Five states – Michigan, Wisconsin, Minnesota, Ohio, and Pennsylvania – filed a lawsuit against the U.S. Army Corps of Engineers and Metropolitan Water Reclamation District of Greater Chicago (District) in federal district court. 

September 2010: President Obama named an “invasive carp Czar,” John Goss, as the chairman of the Invasive Carp Regional Coordinating Committee to oversee the government-led effort to control the species. 

October 2010: Indiana crews complete a nearly 1,200-foot-long, 8 feet high fence designed to prevent adult carp from using the northeastern Indiana marsh to swim from the Wabash River system into the Maumee River and then onto Lake Erie during floods. A 13-mile concrete and steel mesh fence that splits the narrow divide between the Des Plaines River and the Chicago Sanitary and Ship Canal was also completed.
Eagle Marsh Fence
(Credit: Indiana Department of Natural Resources)

December 2010: In collaboration with other Federal and State Agencies, local governments and non-governmental organizations, the USACE launches the Great Lakes and Mississippi River Interbasin Study (GLMRIS). GLMRIS will explore options and technologies, collectively known as Aquatic Nuisance Species (ANS) controls, that could be applied to prevent ANS transfer between the basins through aquatic pathways. 

March 2011: Bighead carp is listed as “injurious” species under federal Lacey Act, making transfer of live fish illegal. The Corps of Engineers acknowledges that the Chicago Sanitary and Ship Canal’s electric-dispersal barriers were only effective for large fish, defined as 5.4 inches or longer. 

April 2011: Barrier IIB begins full-time operation, 100 feet away from Barrier IIA.

August 2011: The U.S. Court of Appeals for the Seventh Circuit rejected the Great Lakes states’ request for a preliminary injunction. 

January 2012: A study, “Restoring the Natural Divide: Separating the Great Lakes and Mississippi River Basins in the Chicago Area Waterway System,” is released by the Great Lakes Commission and the Great Lakes and St. Lawrence Cities Initiative showing that separating the Great Lakes and Mississippi River basins to prevent the spread of invasive carp and other invasive species is not only feasible both technically and economically, but is also a natural step toward much-needed action to improve Chicago’s water infrastructure. The study provides three options for creating a permanent hydrologic barrier between Lake Michigan and the Mississippi River basin. Building the barriers would cost between $3 billion and $9 billion and take at least a decade to complete, according to the study. 

July 2012: The Department of Fisheries and Oceans Canadian released a study affirming that all five Great Lakes are hospitable to invasive carp and that once established the non-native fish will likely disrupt the native fishery, alter the ecosystem and create another food web. The study found that it would take as few as 10 female and 10 or fewer male invasive carp of reproductive age to reproduce in the Great Lakes. Officials announced that six water samples taken from Sandusky and north Maumee bays tested positive for the presence of invasive​ carp environmental DNA in Michigan and Ohio waters. Four samples from Sandusky Bay, in Ohio waters, tested positive for bighead carp eDNA.

December 2012: The U.S. District Court for the Northern District of Illinois dismissed the lawsuit filed two years ago by the states of Michigan, Wisconsin, Minnesota, Ohio, and Pennsylvania, ruling that hydrologic separation of the Great Lakes and Mississippi River Basins is precluded by federal laws that require the U.S. Army Corps of Engineers to sustain through navigation between the water bodies.

February 20, 2013: An interim report for the Invasive Carp Environmental DNA Calibration Study (ECALS) was released. ECALS is a three-year study to improve the understanding and interpretation of invasive carp environmental DNA (eDNA) results. ECALS will investigate alternate sources of invasive carp DNA, improve existing genetic markers and investigate the relationship between the number and distribution of positive eDNA samples with the density of invasive carp populations. The results of this study will allow project managers to better interpret eDNA results, as well as investigate ways to make the eDNA process more efficient.

May 2013: The Invasive Carp Regional Coordinating Committee (ACRCC) released its 2013 Invasive Carp Monitoring and Response Plan (MRP). Outlining a revised and aggressive set of actions to track and remove invasive carp in the Upper Illinois River and the Chicago Area Waterway System (CAWS), the 2013 MRP is again designed to prevent invasive carp from establishing populations in the CAWS and Lake Michigan. The 2013 MRP details over $6.5 million of monitoring, sampling and response activities to be conducted by multiple members of the Invasive Carp Regional Coordinating Committee. The plan outlines actions for the current (2013) field season focused on monitoring and removal of invasive carp in the Chicago Area Waterway System (CAWS) and upper Illinois Waterway; and on-going evaluations of the effectiveness of barriers and gears used in keeping invasive carp from establishing in the CAWS and Lake Michigan. 

July 2013: ACRCC released the 2013 Invasive Carp Control Strategy Framework. The 2013 version adds several initiatives to the proactive effort to combat invasive carp, including testing and deployment of new physical and chemical control tools, strengthening the electric barrier system in the Chicago Area Waterway System, and constructing a new project to physically separate the Great Lakes and Mississippi River basin at Eagle Marsh near Fort Wayne, Indiana. 

October 2013: Scientists confirmed for the first time that at least one variety of invasive carp is living and breeding in the Great Lakes watershed. Four fertile grass carp, discovered in the Sandusky River, were found to have been bred and born in those waters, and not been stocked or transported from elsewhere. Grass carp are one of four species of invasive carp that have been working their way through U.S. waters, but are different from the silver and bighead carp that officials are trying to keep out of the Great Lakes. While the silver and bighead carp are of more concern, grass carp also pose a risk to the Great Lakes ecosystem. They eat large quantities of aquatic plants, which could degrade areas important for spawning and early development of native fish and could be detrimental to ducks, geese or other large aquatic birds that rely on aquatic vegetation for food and shelter. As well, the discovery of grass carp breeding in a Great Lakes tributary suggests other breeds of invasive carp could establish themselves if they reach local waters. 

November 2013: Authorities announced that a second positive DNA hit for the invasive carp was detected in Lake Michigan. (The first positive eDNA hit was from a water sample taken in 2010 in Calumet Harbor, outside of Chicago.) A water sample taken from Lake Michigan’s Sturgeon Bay in Wisconsin in May of 2013 tested positive for DNA from silver carp. The May testing included 50 water samples taken from the Green Bay area; they were among 282 from other areas along Lake Michigan. As a result of the finding, the Wisconsin DNR and the U.S. Fish and Wildlife Service will take more samples from the area to determine whether the positive hit was a fluke or something worse.

January 6, 2014: The U.S. Army Corps of Engineers released the Great Lakes and Mississippi River Interbasin Study (GLMRIS) Report. The GLMRIS Report presents options for preventing movement of invasive carp and other invasive species into the Great Lakes from the Chicago waterways. The report contains eight alternatives, each with concept-level design and cost information, and evaluates the potential of these alternatives to prevent, to the maximum extent possible, the spread of 13 identified aquatic nuisance species, to include invasive carp. The options concentrate on the Chicago Area Waterway System (CAWS) and include a wide spectrum of alternatives ranging from continuing current activities to complete separation of the watersheds. Each alternative includes mitigation measures evaluated for potential impacts to water quality, flood-risk management, natural resources and navigation. The report does not provide a recommendation for action, but it lays some of the necessary groundwork for building a physical barrier that restores the natural Great Lakes-Mississippi River basin divide.

May 2014: The U.S. Army Corps of Engineers released a summary of comments submitted and recorded for administrative record during the public comment period for the Mississippi River Interbasin Study (GLMRIS) Report. The comment summary includes information on the study; the public comment process; a summary of comments by location and themes; commenter demographic information; Corps clarification on several recurring themes; and the path forward on GLMRIS. More than 1,600 comments were submitted from more than 1,800 individuals, organizations, state and local government agencies from 43 states, and the Canadian provinces of Ontario, Quebec, and British Columbia. This does not include input provided though letter-writing campaigns. 

June 2014: ACRCC released its 2014 Invasive Carp Monitoring and Response Plan (MRP). The 2014 Monitoring and Response Plan outlines actions for the 2014 field season focused on monitoring and removal of invasive carp downstream of the Electric Barrier System in the Chicago Area Waterway System (CAWS) and the upper Illinois Waterway, and on-going evaluations of the effectiveness of barriers and gears used in keeping invasive​ carp from establishing in the CAWS and Lake Michigan.

October 2014: A single sample of DNA from a silver carp was discovered in the Kalamazoo River in Michigan. Two hundred water samples were taken in July 2014 along the Kalamazoo River and one of the of 200 samples tested positive for silver carp eDNA. The positive sample was taken from just below the Caulkins Dam. This sample represents the first time that Michigan has experienced a positive result for silver carp eDNA in Michigan’s Great Lakes waters outside of Maumee Bay. As a result of the finding, additional samples will be taken this month, MDNR staff will increase their presence along the Kalamazoo River to enlist anglers to report any invasive carp sightings, and MDNR will be putting information in local bait shops to increase public awareness. 

A single positive sample for silver carp was also identified from 200 samples taken this summer in the Fox River, a tributary of Lake Michigan in Green Bay, Wisconsin. This is the second discovery of eDNA in Wisconsin. The DNR reported on Nov. 5, 2013, that a sample of a silver carp had been found near Potawatomi State Park, where Sturgeon Bay opens to Green Bay. Subsequent testing in the area failed to turn up any new positives.

In addition to the rivers in Wisconsin and the Kalamazoo in Michigan, the following Michigan waters were tested and showed no evidence of Asian carp DNA: Gallen, Grand, Muskegon, Paw Paw and St. Joseph.