Between 23 August and 5 September 2010, 27sites on the Illinois River waterway and one site in Reach 26 of the Mississippi River were sampled using AC electrofishing to monitor fish communities. A total of 5,412fishesrepresenting 61species (plus two hybrids) from15 families were collected during 26.01 hours of sampling. Collections made in 2010 indicated continued high catches of gizzard shad, emerald shiner, and bluegill throughout most of the Illinois River waterway. Several fish species were collected for the first time within a given river reach in 2010, including northern pike, brook silverside, and silver redhorse. Gizzard shad were the most abundant species collected throughout the waterway in 2010with 1,430 fish collected comprising 26.4% of the total catch. The sample from Lambie’s Boat Harbor (RM 170.3, Peoria Reach) yielded the highest collection of total fish (1,049, 19.4% of the total collection), while the sample from Johnson Island (RM 249.6) produced the lowest total fish (31, 0.6% of the total collection). Fish species richness at sites ranged from 25 at Clark Island (RM 215.3, Peoria Reach) to 8 species at the Mouth of the DuPage (RM 277.4, Dresden Reach). Important sportfish species such as bluegill, largemouth bass, and channel catfish were collected in all six waterway reaches in 2010. Bluegill catch per unit effort in number of fish collected per hour (CPUEN) ranged from 65.20in Peoria Reach to 2.67in Alton Reach. Largemouth bass CPUEN ranged from 19.07in Peoria Reach to 1.17in Alton Reach. Channel catfish CPUEN ranged from 25.33in Alton Reach to 0.00in Dresden Reach. Biomass catch per hour (CPUEW) was highest in the Peoria Reach yielding181.56pounds per hour. Silver carp biomass ranked first over all reaches at 82.98pounds per hour, comprising 40.92%of the total biomass. Common carp ranked among the top three fish species in CPUEW in every reach, except Dresden Reach where it ranked fourth. Catch in weight for silver carp was the highest ever observed in a given reach in F-101-R sampling. Between 15 June and 31 October 2010, 37,174 fish were collected with a total biomass of 12,087.60 pounds representing 96 species and 8 hybrids from20 families during 80.25 hours of pulsed-DC electrofishing in the Illinois, Mississippi, Ohio, and Wabash rivers. Gizzard shad were the most abundant species by number, (37.8% of catch, 14,065 fish) followed by emerald shiner (21.1 % of catch, 7,866 fish), freshwater drum (3.0% of catch, 1,097 fish), channel catfish (2.5% of catch, 936 fish), and common carp (2.3% of catch, 835 fish). Common carp contributed the greatest biomass (33.5% of catch, 4,043.79 lbs) followed by smallmouth buffalo (9.6% of catch, 1,164.05 lb), silver carp (9.4% of catch, 1,140.48 lbs), channel catfish (7.9% of catch, 950.96 lbs), and freshwater drum (1.5% of catch, 186.65 lbs). In general, pulsed-DC electrofishing catches were dominated in number and biomass by forage and non-sport species. However, channel catfish were among the top five species contributing the most biomass to the overall catch in each river and were the most commonly collected sportfish by number and biomass across all rivers. Bluegill were among the top five species contributing the most individuals to the catch in the Illinois River during Time Periods1 and 2 and in the Ohio River during Time Period 3. Spotted bass made up 5.8% of the catch in numbers and was the fifth most numerous species collected in Time Period 3 from the Wabash River. Gill and hoop net collections between 1 November and 16 November, 2010 yielded 83 fish representing 13 species and 1 hybrid from 79 gill net, hoop net, and benthic hoop net sets. Channel catfish was the most abundant species by number (23, 27.7%) while flathead catfish contributed the most biomass (73.57 lb, 46.8&). Gill and hoop net collections between 5 April and 18 May 2011 yielded 718 fish representing 20 species and 1 hybrid from 9 families from 126 gill and hoop net sets. Shovelnose sturgeon was the most abundant species in terms of number (465, 64.7%) and biomass (771.1lb, 53.5%).