Monitoring and Assessment of Aquatic Life in the Kaskaskia River for evaluating IDNR Private Lands Programs: Annual Report 2015

Summer thermal characteristics were monitored at 81 locations in the basin (Figure 3) during the three years of this study. Mean daily summer temperature ranged from 18.9oCto 27.2oC with a mean of 23.5oC. Water quality parameters were measuredduring152site visits in summer and 60 site visits infall between 2013 and 2015. Mean values for these parameters were similar in summer and fall (Table 2) and are characteristic of Midwestern watersheds with high densities of agricultural land use. Fish were collected during123sampling events between 2013 and 2015.Mean standardized abundance (number of individuals per 100m of sampled stream) was 323.3 and mean standardized species richness (number of species per 100m of sampled stream) was 11.8. Index of Biotic Integrity(Smogor 2000)scores calculated from sampled fish assemblages had a range of13 (very low) to 55(moderate) and a mean of 36.3(indicating an average condition within the moderately low category; Table 3).The seven overall most abundant fish species in wadeable streams of the Kaskaskia River watershed were all minnows, but that pattern varies by subwatershed (Table 4). Green sunfish is the most frequently collected species in the watershed and in three of the four subwatersheds; however, frequency of occurrence patterns vary across the subwatersheds amongst the remaining species(Table 5).QHEI scores (OEPA 2006) for the watershed range between 21 (impaired) and 77.5 (excellent) with a mean of 51.8 (moderate, Table 6). IHI scores (Sass et al. 2011) for the watershed range between5 and 24 (which are the minimum and maximum scores possible) with a mean of 18.3, which is near the middle of the index gradient (Table 7).Work conducted during this reporting period was performed primarily by one FTE research scientist aided by the Principle Investigators, two graduate students and three hourly workers. A total of eleven hourly workers (mainly undergraduate students) have assisted staff during the three years of study.