THE LONG-TERM ILLINOIS, MISSISSIPPI, OHIO, AND WABASH RIVERS FISH POPULATION MONITORING PROGRAM 2013

This report presents a summary of those data collected during segment 25(2013-14) of the Long-term Illinois, Mississippi, Ohio, and Wabash Rivers Fish Population Monitoring Program(LTEF), an annual survey executed by members of the Illinois Natural History Survey with funds administered by the U.S. Fish and Wildlife Service and the Illinois Department of Natural Resources. Sampling for the LTEF program was conducted throughout the state’s largest rivers: six reaches of the Illinois River Waterway, six segments or pools of the Mississippi River, four segmentsor pools of the Ohio River,five segments of the Wabash River, and navigable portions of the Iroquois and Kankakee Rives. In all segments of the LTEF program, all fish species collected were accurately identified, tallied, measured, and weighed. The catchrates of sportfishspecies were calculated as the number of individuals collected per hour (CPUEN± standard error).Structural indices [Proportional Size Distribution (PSD) and Relative Weight (Wr)] were also calculated for species of interest to regional managers. Catch rates and species richness varied greatly among all sampling locationsand sampling periods. Emerald shiners and gizzard shad comprised the majority of the individuals caught, while silver carp and common carp accounted for the greatest proportion of the biomass collected in most sampling areasof the survey. The analysis of CPUEN and PSD trends in sportfish populations sampled by the program may indicate inter-annual recruitment patterns in sportfish populations around the state. Both shovelnose sturgeon and blue catfish were the two species most commonly encountered in the gill net surveys.