PISCICIDES AS AN EMERGENCY TOOL FOR CONTROLLING RANGE EXPANSION OF
THE ROUND GOBY (NEOGOBIUS MELANOSTOMUS) IN THE ILLINOIS WATERWAY. 

Wendi Larson, Verdel K. Dawson, Theresa M. Schreier, and Sue Schleis.  
U.S. Geological Survey, Upper Midwest Environmental Sciences Center, La Crosse, WI 54603.

The Illinois Waterway System provides a direct connection for the continuous transfer of water
from Lake Michigan to the Mississippi River and is presumed responsible for the transfer of
certain exotic species from Lake Michigan to the Mississippi River basin.  Recent surveys
suggest that the exotic species, Neogobius melanostomus (round goby), has invaded the Illinois
Waterway System from Lake Michigan via the Calumet River drainage.  To prevent the spread of
round goby populations into the Mississippi River, conservationists plan to install an electrical
barrier across the Illinois Waterway.  As populations spread beyond this barrier site, however, the
use of piscicides is being considered as an additional control method.  Newly developed
delayed-release formulations of Bayluscide( and antimycin may be ideal toxicants for reducing
bottom-dwelling round goby populations without negatively impacting native fish populations in
the water column.  To determine if Bayluscide( and antimycin are effective piscicides for
controlling round goby populations we 1) tested their avoidance/attraction behavior to each
chemical and 2) established their minimum effective contact time to each chemical.  Round goby
did not demonstrate avoidance behavior to either Bayluscide( or antimycin, and the minimum
effective contact time indicated that a few minutes of exposure to each chemical was lethal. 
These results suggest that applications of Bayluscide( and antimycin may be effective in reducing
the expansion of round goby populations in the Illinois Waterway System.  

Keywords:  piscicides, round goby, exotic species, Bayluscide(, antimycin