bighead carp

:  a freshwater, cyprinid fish (Hypophthalmichthys nobilis) that has a large head and mouth, a ventral keel between the anal and pelvic fins, and a blotchy, dark-gray color and that is native to eastern Asia and has been widely introduced into nonnative waters where it is often considered a pest The bighead carp, which can grow to 100 pounds, have caused environmental havoc in rivers and lakes in the South and Midwest because they devour huge volumes of food. — Gene Schabath, Detroit News, 22 Dec. 2003 Silver and bighead carp are filter feeders that compete for diminishing plankton stocks with native fishes and mollusks. — Kathy Etling, St. Louis Post-Dispatch, 10 May 2008 ◆Bighead carp is considered an invasive species in the U.S. where it has had a detrimental environmental impact due to its voracious appetite, especially for zooplankton, and rapid reproduction.