Carp are not native to North American waters, but various carp species have been introduced here since the mid-1800s, much to the detriment of native fish. Although carp eradication measures have been active for over 100 years, long-established species, like the common carp, are present in almost every state.
Asian carp (bighead, black, grass, and silver carp) were imported to the United States in the 1970s as a method to control nuisance algal blooms in wastewater treatment plants and aquaculture ponds as well as for human food. Within ten years, the carp escaped confinement and spread to the waters of the Mississippi River basin and other large rivers like the Missouri and Illinois.
Asian carp are in direct competition with native aquatic species for food and habitat. Their rapid population increase is disrupting the ecology and food web of the large rivers of the Midwest. In areas where Asian carp are abundant, they have harmed native fish communities and interfered with commercial and recreational fishing.
Experts are extremely concerned about the consequences of Asian carp invading the Great Lakes, where the carp would negatively affect the $7 billion-a-year fishing industry.