SPATIAL DISTRIBUTION OF FISH NEAR INDUSTRIAL WARM WATER OUTFLOWS ON POOL 19 OF 
THE MISSISSIPPI RIVER DURING COLD WATER CONDITIONS.

Joe DeBold, Dr. Timothy Spier, David Wyffels
Department of Biological Sciences, Western Illinois University, 1 University 
Circle, Macomb, Il 61455

It is well known that various species of fish congregate within warmer waters 
during cold water conditions.  This study aims to show species composition, size 
distribution and microhabitat utilization in relation to these warm water 
outlets in Pool 19 of the Mississippi River.  During this experiment we randomly 
spot sampled two warm water outlets on the Iowa shoreline of pool 19 with a DC 
electrofishing boat.  We also sampled two shoreline areas that had no warm water 
outlets and compared fish species found and catch per unit effort.  Preliminary 
results showed temperatures ranging from 1.9 0C to 13.2 0C.  Common carp 
(Cyrinus carpio) and gizzard shad (Dorosoma cepedianum) were the only fish 
species utilizing these warm water outlets during cold water conditions.  The 
majority common carp were found in water temperatures from 80C to 120C, whereas 
gizzard shad were found in water temperatures from 30C to 90C.  All fish were 
found within 15 meters of warm water outlets which is closer than we expected.  
Temperature, conductivity and bathometric maps were constructed of the warm 
water plumes using GIS and were compared to the spatial distribution of fish 
species.
      
Keywords: Mississippi River, Pool 19, Dorosoma cepedianum, Cyrinus carpio, GIS