14:45 - 15:00
ECOSYSTEM RESPONSES TO ASIAN CARP INVASION AND CONTROL: PATTERNS OF RIVERINE ZOOPLANKTON ABUNDANCE, BIOMASS, AND COMPOSITION Asian carp exert a strong indirect pressure on ecosystems through the planktivory. This talk summarizes projects that examine river zooplankton response to the arrival and removal of Asian carp over a 20 year period in the Illinois River. Plankton responses examined include; shifts in community composition since pre-Asian carp conditions, longitudinal patterns of plankton composition across a 250 kilometers gradient of Asian carp abundance, and an assessment of the potential for rapid recovery of the zooplankton to localized carp removals of between 2 -20 tones from a single floodplain backwater. Since Asian carp establishment in 2000, zooplankton abundance and biomass have both dramatically decreased. Although large bodied cladocerans and copepods were most affected the highly abundant rotifers, dominant in this and other large rivers systems, was also significantly reduced even though rotifer biomass was unaffected. Plankton community composition and dominance shifts markedly as carp arrived in 2000 but, to date, the localized removal efforts of a commercial fishing program have not reversed these shifts, even at a local level.
Andrew Casper (Primary Presenter/Author), Illinois Natural History Survey, firstname.lastname@example.org;
Collin J. Hinz (Co-Presenter/Co-Author), Illinois Natural History Survey, University of Illinois, email@example.com;
Richard M. Pendleton (Co-Presenter/Co-Author), Illinois Natural History Survey, University of Illinois, firstname.lastname@example.org;