Seasonal Water Area Uses of Asian Carp in The Upper Illinois River Waterway Using Acoustic Telemetry.

Asian Carp are a highly invasive species introduced into the Mississippi River System in the mid-1970s and now, due to expanding populations, are a pervasive threat to invading the Great Lakes. The Dresden Island, Marseilles, and Starved Rock Asian Carp populations in the upper Illinois River waterway (leading edge) pose the greatest risk to the Great Lakes. Therefore, understanding their habitat use and behavior in this region is important to enhance removal efforts and restrict further expansion. The objectives of our study were to determine habitat preferences and identify areas of concentration of silver carp, bighead carp, and grass carp at their leading-edge population using acoustic telemetry. Asian carp species were tracked from March 2018 - October 2019 using a mobile Vemco VR-100 receiver at pre-defined grid points (0.54 km apart) within the three pools. Detections from 213 tagged Asian Carp have been used to identify seasonal water use associations (100 in Dresden Island, 55 in Marseilles, and 58 in Starved Rock), with unique patterns persisting in each pool. In the Dresden Island Pool Asian Carp move between tributary channels, and floodplain lakes. In the Marseilles Pool Asian Carp reside seasonally in floodplain lakes and the main navigation channel. In the Starved Rock Pool Asian Carp utilize secondary channels of the pool. Statistics were completed in R detailing habitat selectivity and maps were created in ArcMap showing densities of Asian Carp in each of three pools.