A long tradition of Asian carp exists in Chinese culture and literature. A popular lyric circulating as early as 2000 years ago in the late Han period includes an anecdote which relates how a man far away from home sent back to his wife a pair of carp (Chinese: 鯉魚; pinyin: Liyu), in which, when the wife opened the fish to cook, she found a silk strip that carried a love note of just two lines: “Eat well to keep fit” (first line) and “Missing you and forget me not” (second line).
At the Yellow River at Henan (Chinese: 河南; pinyin: Hénán; Wade–Giles: Ho-nan) is a waterfall called the Dragon Gate. It is said that if certain carp called yulong can climb the cataract, they will transform into dragons. Every year in the third month of spring, they swim up from the sea and gather in vast numbers in the pool at the foot of the falls. It used to be said that only 71 could make the climb in any year. When the first succeeded, then the rains would begin to fall. This Dragon Gate was said to have been created after the flood by the god-emperor Yu, who split a mountain blocking the path of the Yellow River. It was so famous that throughout China was a common saying, "a student facing his examinations is like a carp attempting to leap the Dragon Gate."
Henan is not the only place where this happens. Many other waterfalls in China also have the name Dragon Gate and much the same is said about them. Other famous Dragon Gates are on the Wei River where it passes through the Lung Sheu Mountains and at Tsin in Shanxi Province. The fish's jumping feature is set in such a proverbial idiom as "Liyu (Carp) jumps over the Dragon Gate (Chinese: 鯉躍龍門)," an idiom that conveys a vivid image symbolizing a sudden uplifting in one's social status, as when one ascends into the upper society or has found favor with the royal or a noble family, perhaps through marriage, but in particular through success in the imperial examination. It is therefore an idiom often used to encourage students or children to achieve success through hard work and perseverance. This symbolic image, as well as the image of carp itself, has been one of the most popular themes in Chinese paintings, especially those of popular styles. The fish is usually colored in gold or pink, shimmering with an unmistakably auspicious tone. Yuquan (玉泉 in Chinese), one of the well-known scenic spots in Hangzhou, has a large fish pond alive with hundreds of carp of various colors. A three-character inscription, Yu-Le-Guo (鱼乐国), meaning "fish’s paradise", is set above one end of the pond in the calligraphy of a famous gentry-scholar of the late Ming Dynasty named Dong Qichang (Chinese: 董其昌). Many tourists feed the fish with bread crumbs.
Among the various kinds of carp, the silver carp is least expensive in China. The grass carp is still a main delicacy in Hangzhou cuisine. Restaurants along the West Lake of the city keep the fish in cages submerged in the lake water right in front of the restaurant; on an order from a customer, they dash a live fish on the pavement to kill it before cooking. The fish is normally served with a vinegar-based sweet-and-sour sauce (Chinese: 西湖醋魚).
Silver carp have become notorious for being easily frightened by boats and personal watercraft, which cause them to leap high into the air. The fish can jump up to 2.5–3.0 m (8–10 ft) into the air, and numerous boaters have been severely injured by collisions with the fish. According to the EPA, "reported injuries include cuts from fins, black eyes, broken bones, back injuries, and concussions.". Silver carp can grow to 45 kg (100 lb) in mass. This behavior has sometimes also been attributed to the very similar bighead carp, but this is uncommon. Bighead carp do not normally jump when frightened. Catching jumping carp in nets has become part of the Redneck Fishing Tournament, in Bath, Illinois. Other parties, such as the Peoria Carp Hunters, have taken advantage of the jumping ability as a mechanism of hunting the carp, in some cases to purge the invasive species.
Asian carp have been a popular food fish in Asia for thousands of years. Some recipes are specifically for carp such as Tángcù Lǐyú (sweet-and-sour carp) and Koikoku (thick miso soup with carp). However, many people in North America associate Asian carp with common carp, a bottom-feeding, highly bony species which was introduced from Eurasia in the 1800s and is not widely regarded as food.
The pearly white flesh—complicated by a series of bones—is said to taste like cod or described as tasting like a cross between scallops and crabmeat. They are low in mercury because they do not eat other fish. To make the fish more appealing to American consumers, the fish have been renamed silverfin or Kentucky tuna. Volunteer efforts to increase the popularity further include making and selling carp-based dishes and using the entrails to make fertilizer.
Some have thought to collect the carp eggs for caviar, since one bighead carp was found with over 2 million eggs. Two million eggs from one fish could fill two jars of caviar, which would be quite valuable. This is only true, however, in the case of a fish from which people would eat eggs. As of now, no market for carp eggs exists in America, though there is a movement that is trying to increase the popularity of carp eggs in Europe.
In April 2015, a company called BareItAll Petfoods, based in Chicago, created the first commercially available pet food featuring Asian carp as a means to reduce the populations in the waterways of the Midwest.
Asian carp are an invasive species. Some species of Asian carp cause harm when they are introduced to new environments. The black carp feeds on native mussels and snails, some of which can be already endangered. Grass carp can alter the food webs of a new environment by altering the communities of plants, invertebrates, and fish. Silver carp feed on the plankton necessary for larval fish and native mussels.
Because of their prominence, and because they were imported to the United States much later than other carp native to Asia, the term "Asian carp" is often used with the intended meaning of only grass, black, silver, and bighead carp. In the US, Asian carp are considered to be invasive species. Of the Asian carp introduced to the United States, only two (crucian and black carp) are not known to be firmly established. Crucian carp is probably extirpated. Since 2003, however, several adult, fertile black carp have been captured from the Atchafalaya and other rivers connected to the Mississippi River. Dr. Leo Nico, in the book Black carp: Biological Synopsis and Risk Assessment of an Introduced Fish, reports that black carp are probably established in the United States. In South Florida, the local water management district actually stocks the canals with sterilized grass carp to control the hydrilla plant, which tends to block the locks and drainage valves used to control water flow from the Everglades.
The common carp was brought to the U.S. in 1831, and has been widespread for a long time. In the late 19th century, it was distributed widely throughout the United States by the United States Fish Commission as a foodfish. However, common carp are not now normally prized as a foodfish in the United States. They are often known to uproot vegetation and muddy water through their habit of rooting in the mud for food. They are thought often to have detrimental effects on native species. However, in Europe, common carp are prized as a sportfish, and angling for common carp is enjoying increased popularity in the United States.
In the 1970s, fish farmers in mostly Southern states began importing Asian carp from China to help clean their commercial ponds. The rise in the populations of bighead and silver carp has been dramatic where they are established in the Mississippi River basin. Although many sources cite the record floods of the 1990s as the means by which Asian carp escaped aquaculture ponds into the Mississippi River, this is apocryphal. At least one known escape of bighead carp from aquaculture ponds occurred in 1995, but bighead and silver carp were established in the Mississippi River basin prior to 1990. Grass carp have been reproducing in the Mississippi River since the 1970s.
Bighead, silver, and grass carp are known to be well-established in the Mississippi River basin (including tributaries), where they at times reach extremely high numbers, especially in the case of the bighead and silver carp. Bighead, silver, and grass carp have been captured in that watershed from Louisiana to South Dakota, Minnesota, and Ohio. Grass carp are also established in at least one other watershed, in Texas, and may be established elsewhere.
The Asian carp have recently been found in Lake Calumet in Illinois. Grass carp have been captured in every Great Lake except Lake Superior, but so far, no evidence indicates a reproducing population, although a juvenile grass carp was caught in a river leading to Lake Scugog. No silver carp or black carp have yet been found in any Great Lake. Common carp are abundant throughout the Great Lakes. Current records of where Asian carp have been captured may be found at the United States Geological Survey's Nonindigenous Aquatic Species website.
These fish are thought to be highly detrimental to the environment in parts of the United States. Because of these concerns, the U.S. Fish and Wildlife Service convened stakeholders to develop a national plan for the management and control of invasive Asian carp (referring to bighead, silver, black, and grass carp). The plan was accepted by the National Aquatic Nuisance Species Task Force in the fall of 2007.
In July, 2007, the U.S. Department of the Interior declared all silver carp and largescale silver carp to be injurious species under the Lacey Act. In July 2012, Congress included the "Stop Invasive Species Act" as an amendment to a transportation bill it approved. The act requires the U.S. Army Corps of Engineers to speed up implementation of strategies to protect the Great Lakes from Asian carp.
Bighead and silver carp feed by filtering plankton from the water. The extremely high abundance of bighead and silver carp has caused great concern because of the potential for competition with native species for food and living space. Because of their filter-feeding habits, they are difficult to capture by normal angling methods.
In Canada, the federal Department of Fisheries and Oceans has evaluated the risk of Asian carp invading Canadian waters, particularly the Great Lakes, either by introduction from the Mississippi or through the market in live carp. A few bighead and grass carp have been captured in Canada's portions of the Great Lakes, but no Asian carp (other than common carp, an originally Eurasian species) is known to be established in Canada at this time. Concerns exist that the silver carp may spread into Cypress Hills in Alberta and Saskatchewan through Battle Creek (Milk River), the Frenchman River, and other rivers flowing south out of the hills into the Milk River. In Mexico, grass carp have been established for many years in at least two river systems, where they are considered invasive, but no other Asian carp are known to have been introduced.
The United States Environmental Protection Agency is also concerned about the possibility of Asian carp migrating to the Great Lakes. In 2002, the U.S. Army Corps of Engineers completed an electric fish barrier in the Chicago Sanitary and Ship Canal, the only navigable aquatic link between the Great Lakes and the Mississippi River drainage basins. The initial fish barrier was used as a demonstration project to study the design's effectiveness. Following positive results, construction began on a second, permanent barrier in 2004. In addition to the canal, the corps has identified 18 sites in five additional states, from Minnesota to New York, that could allow for movement of Mississippi basin carp into the Great Lakes.
U.S. Representative Dave Camp from Michigan's 4th district and Senator Debbie Stabenow of Michigan introduced the Close All Routes and Prevent Asian Carp Today (CARPACT), which directs the Army Corps of Engineers to take action to prevent Asian carp from entering the Great Lakes, which is estimated to cost more than $30 million in 2010. The act will make sure the locks and sluice gates at the O’Brien Lock and Dam and the Chicago Controlling Works are closed and remain closed until a better strategy is developed. The act will also enhance existing barriers and monitoring systems by giving authority to the Army Corps of Engineers to obtain real estate necessary for the construction and maintenance of the barrier. The corps also has the authority to eliminate and prevent the spread of the carp using fish toxicants, commercial fishing and netting, and harvesting. A new report issued in 2012 by the Great Lakes Commission concludes that physical separation of the Great Lakes and the Mississippi River watersheds is the best long-term solution to prevent Asian carp and other invasive species from migrating between the waterbodies.
In November, 2009, carp genetic material was detected beyond the two electric barriers, leaving only a single lock/dam on the Calumet River between the detected presence and Lake Michigan. "This is absolutely an emergency", Joel Brammeier, acting president of the Alliance for the Great Lakes, was quoted as saying, referring to the ecological threat, and also mentioning the threat to recreational boaters. "Mr. Brammeier and some others called for the immediate closing of the lock ... though others doubted it was feasible to stop shipping traffic [there]." "All options are on the table", said Jacqueline Y. Ashmon, a spokeswoman for the Corps of Engineers. "We don’t have any specifics."
In the first week of December, 2009, the Army Corps made plans to shut down one of the electric barriers for maintenance, and the Illinois Department of Natural Resources responded by dumping 2,200 gallons of the toxin rotenone into the canal. Rotenone, the report said, is deadly for fish, but not harmful to humans, animals, or most other aquatic life. While "scores" of fish were killed, only one carp was found, near Lockport Lock and Dam and nearly six miles below the electronic barriers. The fish kill cost $3 million and produced 90 tons of dead fish, reported one commentator, who also noted a parallel with an intentional fish kill in Chicago, in Lincoln Park's South Pond, by the IDNR in November, 2008.
Other efforts to reduce the number of Asian carp have included encouraging the public to eat more carp and fisheries shipping the fish to other markets, such as Israel, and have included the participation of then Secretary of State Hillary Clinton.
On June 22, 2010, a 19-pound Asian carp was found near the shore of Lake Michigan, in Lake Calumet, about six miles downstream from Lake Michigan, by a commercial fisherman hired by the state of Illinois to do routine fish sampling in the area. The fish confirms DNA evidence that Asian carp have indeed breached the electric fish barrier on the Chicago Sanitary and Ship Canal.
Stopping these invasive carp from spreading into Lake Erie is another concern to many involved, as Lake Erie provides the ideal habitat for the carp to survive. This could lead to the fish choking out the other native fish that exist there. Ohio has a multimillion-dollar sport fishing and boating industry. Allowing these fish to choke out native species would cause a huge hit to this industry. This is especially true since catching these carp with traditional fishing methods is so difficult, which makes it harder for the industry to shift the sport fishing from one fish to another.
On August 24, 2010, a carp reportedly knocked a kayaker out of competition in a Missouri River race at Lexington in western Missouri.
On September 8, 2010, the Council on Environmental Quality announced the appointment of John Goss as the Asian Carp Director. Goss' role is primarily to serve as the principal advisor to the CEQ's chair, Nancy Sutley on Asian carp issues, and oversee federal, state, and local coordination on Asian carp control efforts. Goss was previously executive director of the Indiana Wildlife Federation (a state affiliate of the National Wildlife Federation), director of the Indiana Department of Natural Resources, and vice-chairman of the Great Lakes Commission.
The Stop Asian Carp Act of 2011 was introduced to require the Secretary of the Army to study the feasibility of the hydrological separation, such as electric barriers, of the Great Lakes and Mississippi River basins. The act provided 30 days for the Secretary of the Army to begin a study on the best means of implementing a hydrological separation of the Great Lakes to prevent the introduction of Asian carp. The study requirements included researching techniques that prevented the spread of carp from flooding, wastewater and storm water infrastructure, waterway safety operations, and barge and recreational traffic.
In 2012, the U.S. Senate and House introduced new bills aimed at combating the spread of Asian carp into the Great Lakes by expediting some items of the Stop Asian Carp Act of 2011. The legislation provides direction to the U.S. Army Corps of Engineers to complete their study within 18 months on how to separate the Great Lakes from the Mississippi watersheds. The USGS collaborated with the University of Minnesota to prepare an extensive report on the use of environmental deoxyribonucleic acid (eDNA) to detect a species in a waterway. This report was put together after extensive field research resulting from positive findings of the eDNA of Asian carp in Minnesota waterways in 2011. Rivers being researched are the Mississippi and St. Croix Rivers. However, new research was unable to redetect the presence of Asian carp, although several have been caught in Minnesota over the past two years. Possibilities of why Asian carp were not detected include a change in the method of sampling or a disappearance of the carp from Minnesota waterways.
The Upper Mississippi CARP Act was presented to Congress as recently as 2013. Presented by Congressmen Ellison of Minnesota, the Upper Mississippi CARP Act would empower the Secretary of the Army to enact strategies previously determined to prevent further spread of Asian carp and begin eliminating the species. Included in this legislation is the requirement for the Army Corp of Engineers to shut down the Upper St. Anthony Falls lock if Asian carp are detected in the portion of the Mississippi River near the Twin Cities. U.S. Senator Amy Klobuchar (DFL) told the Pierce County Herald, “Asian carp not only pose a serious threat to Minnesota’s environment, and they also threaten the recreation and fishing industries that play a key role in the state’s economy. We must do everything we can to stop the further spread of this invasive species into our lakes and rivers, and this legislation will help the state take action to protect Minnesota’s waterways”.
In May 2013, a test for silver carp eDNA in the waters of Sturgeon Bay in Lake Michigan near Green Bay, Wisconsin was positive. The carp are active in May. The result was published in October and scientists will retest in May, 2014.
In July 2015, two grass carp were found within days of each other in contained ponds near Toronto's Lake Ontario waterfront. This could mean a variety of things, but has yet to prove that widespread reproduction is taking place in Lake Ontario, although both fish were male and fertile. The United States and Canadian authorities have been working together to determine where the fish originated and how to stop a potential invasion into the Great Lakes, however in early September three more grass carp were found near the Toronto Islands.
As of 2016, efforts were being made to reintroduce alligator gar between Tennessee and Illinois as part of an effort to control Asian carp.
On December 21, 2009, Michigan Attorney General Mike Cox filed a lawsuit with the U.S. Supreme Court seeking the immediate closure of the Chicago Sanitary and Ship Canal to keep the Asian carp out of Lake Michigan. Neighboring Great Lakes states and the U.S. Army Corps of Engineers, which constructed the canal, are co-defendants in the lawsuit.
In response to the Michigan lawsuit, on January 5, 2010, Illinois Attorney General Lisa Madigan filed a counter-suit with the Supreme Court, requesting it to reject Michigan's claims. The Illinois Chamber of Commerce and American Waterways Operators both sided with Illinois in the lawsuit, filing affidavits (amicus briefs) and arguing that closing the Chicago Sanitary and Ship Canal would upset the movement of millions of tons of vital shipments of iron ore, coal, grain, and other cargo, totaling more than $1.5 billion a year, and contribute to the loss of hundreds, perhaps thousands of jobs. In response, Michigan noted the value of the sport fishing and recreation industry, already heavily affected in other states with large carp populations, would drop by more than $3.0 billion and result in the loss of at least 4,000 jobs. President Obama and his administration supported Illinois's efforts to keep the canal open; with the support of USGS and USFWS, reports have consistently denied the Asian carp poses a threat.
On January 19, 2010, the Supreme Court rejected the Michigan injunction request, but took no action on Michigan's separate request to reopen older cases regarding Chicago water withdrawal from Lake Michigan. The litigation proceeds in lower courts.
On January 1, 2010, the Ontario government also filed a lawsuit (alongside the American states) in an American court to stop the dumping of Asian carp into the Great Lakes, a potentially damaging act to the fishing industry (of Canada).