CS17 Invasive Species
Date: Thursday, June 13, 2002
Time: 11:30:00 AM
Location: Sidney
 
PichlovaR, CILER/University of Michigan- GLERL/NOAA, Ann Arbor, USA, radka.pichlova@noaa.gov
Vanderploeg, H, A, GLERL/NOAA, Ann Arbor, USA, henry.vanderploeg@noaa.gov
 
PREDATORY INTERACTIONS BY CERCOPAGIS PENGOI, A NEW INVADER TO THE GREAT LAKES: PRELIMINARY RESULTS
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Cercopagis pengoi (Ostroumov 1891), a predatory cercopagid native to the Ponto-Caspian region, is one of the most recent invertebrate invaders into the Great Lakes. In Lake Michigan is most abundant in nearshore zone during summer. To examine potential food-web impacts and interactions, we conducted preliminary feeding experiments in large bottles and small enclosures: (1) presenting different cultured zooplankton to C. pengoi, (2) presenting natural zooplankton assemblages to C. pengoi, and (3) confining together C. pengoi and Bythotrephes cederstroemi, a larger predatory cercopagid that successfully invaded Great Lakes two decades ago. C. pengoi preyed on small cladocerans and rotifers, with average consumption of about five items per day, while copepods were able to escape. B. cederstroemi preyed successfully on C. pengoi. Direct observation with video showed that C. pengoi is more slowly moving than B. cederstroemi and thus would be less adept at capturing fast moving prey like copepods.