The Illinois Waterway: A View of the Hydrodynamics and Habitat through the Eyes of Bigheaded Carp

Established reproducing populations for Bigheaded Carp (Hypothalmicthus molitrix and H. nobilis) are found throughout the lower pools of the Illinois River (river miles 0-230).  There is concern over the potential impact these invasive species could have on native ecosystems if they were to become established in the Great Lakes. One potential pathway is the Upper Illinois Waterway (including the Illinois and Des Plaines Rivers and the Chicago Area Waterway System).  Federal and State agencies are collaborating to control the populations and distribution of Bigheaded Carp and gain a better understanding of their life history in the Illinois Waterway.  As part of this effort, U.S. Geological Survey (USGS) scientists are compiling detailed hydrodynamic, bathymetric, and water-quality datasets associated with Bigheaded Carp habitat and populations.   In addition, USGS is simulating the transport and drift of eggs during verified and hypothetical spawning events in the Illinois Waterway.  This information is being used by management agencies to better understand spatial distributions of eggs and larvae in the Waterway, to identify critical early life stage habitat required for recruitment, and to develop controlled harvest strategies for early life stages of Bigheaded Carp.