Changes in the Fish Community at The Nature Conservancy's Merwin Preserve at Spunky Bottoms

The fish community at the Merwin Preserve has undergone several changes over the 15 years of this study, several coinciding with low water levels observed in 2005 and drought events in 2007, 2012, and 2013. The fish community quickly progressed into a sport fish dominated system with abundant native fishes, however all fish populations declined in the mid to late 2000’s, coinciding with low water of 2005 and drought of 2007. As fish communities began to recover, the community shifted to a Common Carp and Bigmouth Buffalo dominated system with drastically reduced sport fish populations in 2012 and 2013. These shifts coincided with additional drought events during those two years. Presently, after the breaching of the levee by 2013 record flooding throughout the Illinois River, the Merwin Preserve is a semi-connected backwater of the Illinois River dominated by Common Carp and Bigmouth Buffalo.