Dear EarthTalk : What exactly are Asian carp, and why are they such a big problem lately? Introduced in the southeast to help control weeds and parasites in aquaculture operations, these fish soon spread up the Mississippi River system where they have been crowding out native fish populations not used to competing with such aggressive invaders. Asian carp are hardy, lay hundreds of thousands of eggs at a time and spread into new habitat quickly and easily. To wit, they can jump over barriers such as low dams. Also, flooding has helped the fish expand into previously unattainable water bodies. Federal and state governments have spent millions in tax dollars accordingly to prevent the carp from making their way into the Great Lakes, but an elaborate underwater electric fence constructed to keep them out has not worked as well as hoped, and policymakers are reviewing other options now. In the states of Michigan, Minnesota, Ohio, Pennsylvania and Wisconsin filed suit in federal court against the U.
Invasion USA: Asian Carp Invaders Have Taken the Mississippi, Are the Great Lakes Next?
Asian carp - Wikipedia
Red triangles indicate occurrences from through The distribution in Kentucky has expanded in recent years. As of , both bighead and silver carp occur commonly in the Mississippi River and the Ohio River up into the Meldahl pool. Bighead carp have been reported all of the way up into the Greenup pool. In addition to the main rivers, these species have also been found in most of their tributaries. This includes the Tennessee, Cumberland, Green and Kentucky rivers along with several others.
In early June, two Quebec fishermen caught an Asian grass carp in the St. Lawrence River. There are several species of Asian carp: silver carp, bighead carp, grass carp and black carp.
Though all are fast growing and prolific feeders that out-compete native fish and can leave a trail of environmental destruction in their wake, the four species of Asian carp do not impact the underwater environment in the exact same ways. Grass carp present significantly different risks to the ecosystem compared to highly invasive bighead carp and silver carp. For more information on the differences between the four species, please refer back to our species pages. We are concerned that if a self-sustaining population of Asian carp becomes established in the Great Lakes it will hurt native fish populations. The four species of Asian carp found in the United States are all fast growing and prolific feeders that are able to out-compete native fish for food, as well as alter the underwater environment so that it is uninhabitable for other native plants and animals.