Midwest Fish & Wildlife Conference 2018

AUTHORS: Seth M. Bogue, Bethany Hoster, Cassi Moody-Carpenter, Anabela Maia, Robert E. Colombo - Biological Sciences Department, Eastern Illinois University

ABSTRACT: The Sangamon River flows approximately 246 miles through central Illinois and is impounded in Decatur for municipal use. Wastewater effluent is discharged into the river below the dam and constitutes the majority of flow during low water periods. Catostomid species exhibiting fin abnormalities have recently been observed in the river reach between Decatur and Springfield. Previous research indicates that caudal fin length of Smallmouth Buffalo and River Carpsucker from this stretch of the Sangamon River respectively comprised 6.98% and 5.48% more of the total body length than that of fish from the Embarras River. We compared morphology of all fins for three species from the Sangamon River to that of the same species from the Embarras River in order to determine the extent of elongation. Landmarks were placed on lateral fish images utilizing tpsDig2 software© and subsequent geometric morphometric analyses was performed with MorphoJ software©. Principal Component Analysis (PCA) was used to highlight differences between populations. Preliminary results show that fins are elongated in the Sangamon River, especially downstream of the wastewater effluent. Fin elongation can negatively affect fish swimming by increasing drag. Future research will be performed to quantify these negative effects by measuring aerobic scope in a flow tank.