The bighead carp (Hypophthalmichthys nobilis) in the Mississippi River Tucker, J. K., F. A. Cronin, R. A. Hrabik, M. D. Petersen, and D. P. Herzog. 1996. The bighead carp (Hypophthalmichthys nobilis) in the Mississippi River. Note in Journal of Freshwater Ecology 11(2):241 243. Reprinted by U.S. Geological Survey, Environmental Management Technical Center, Onalaska, Wisconsin, August 1997. LTRMP 97-R014. 3 pp. (NTIS #PB98-104227) ABSTRACT We report collections of the bighead carp, Hypophthalmichthys nobilis (Richardson, 1845), in the Mississippi River in Missouri and Illinois between 1991 and 1994. In all, we collected 48 specimens ranging from 18 to 790 mm total length. Young-of-the-year fish were caught in 1992 and 1994, which suggests that the species is able to reproduce in the Mississippi River and may become established. Because H. nobilis is a low level filter feeder, its presence may affect other filter feeding fishes such as the paddlefish (Polyodon spathula), bigmouth buffalo (Ictiobus cyrinellus), and gizzard shad (Dorosoma cedpedianum). Further research is needed to confirm that the species is established and what its biological impact will be. KEYWORDS Bighead carp, Hypophthalmichthys nobilis, Illinois, Mississippi River, Missouri