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UMESC
folder.gifInvasive Species

Asian Carp

 Grass Carp
Asian Carps
Why are they a problem?

Types: common, grass, bighead, silver and black carps

Black Carp (Mylopharyngodon piceus)

Black Carp
(Mylopharyngodon piceus)

Common Carp

Common Carp

All four of the Asian carps that are established in the United States spread quickly after introduction, became very abundant, and hurt native fishes either by damaging habitats or by consuming vast amounts of food. Common and grass carps destroy habitat and reduce water quality for native fishes by uprooting or consuming aquatic vegetation.

Bighead and silver carps are large filter-feeders that compete with larval fishes, paddlefish, bigmouth buffalo, and freshwater mollusks (clams). In addition, boaters have been injured by silver carp because they commonly jump out of the water and into or over boats in response to outboard motors. Black carp, which consume almost exclusively mussels and snails, may further threaten our already imperiled native freshwater mussels should they become established.
Fast Facts 
Origin: Eurasia
Preferred habitat: Large warm-water rivers and impoundments.
Size: Commonly 24–30 inches and 3–10 pounds, but individuals of all species can reach 50+ pounds.
Method of introduction: All species were introduced from multiple pathways. Common and grass carps were introduced by government agencies; bighead and silver carps escaped from aquaculture facilities. Black carp are not established; they remain only within aquaculture facilities.
How far have they spread?
Common carp and grass carp have spread or have been introduced legally or illegally into nearly every state in the United States. Bighead and silver carps are spreading rapidly but are found mainly in the Mississippi River drainage basin. Black carp have been collected in the Mississippi River but are not thought to have established reproducing populations at this time.
What are UMESC scientists doing to help?
USGS scientist Lynn Bartsch
 Through partnership with the Long Term Resource Monitoring Program, UMESC scientists have detected and monitored the spread of Asian carps in the Upper Mississippi River. In a joint effort with the USGS Center for Aquatic Resources Studies in Florida, UMESC scientists are conducting a risk assessment for bighead and silver carp. This assessment will be used by the U.S. Fish and Wildlife Service to determine if these species should be listed as injurious wildlife in the Lacey Act. If listed, importation and interstate transportation of these species would be prohibited.


Last updated on January 30, 2004
Contact the Upper Midwest Environmental Sciences Center
http://www.umesc.usgs.gov/invasive_species/asian_carp.html
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