Illinois River - LaGrange Pool

Channel Catfish

Excellent

Channel catfish are one of the primary game fish of the La Grange Pool and they are abundant throughout the reach. Fish over 24 inches weighing 7 to 10 pounds are common. Notable areas for channel catfish are main channel border (area between the navigation channel and the river bank) and side channels with current and structure. The 2025 fish community survey resulted in a catch rate of 5.8 channel catfish/hour electrofishing with fish ranging in size 11-21 inches weighing up to 3.4 pounds. Hoop net surveys are a better gear to evaluate benthic fish populations, like channel catfish. Hoop net surveys on the LaGrange Pool will be conducted in 2026. There remains a one-meal-per-week contaminant advisory on channel catfish over 16 inches in the lower Illinois River due to low level PCB detection in the flesh. PCB contamination in fish is a remnant of past pollution that is declining. Trim the fat, particularly around the belly, and allow fat to drip off the fish when cooking to minimize exposure to PCBs.

Crappie spp.

Good

Both black crappie and white crappie are common in the La Grange Pool. Crappie catch rates in the La Grange Pool were above average in 2025 with over 9/hour of electrofishing collected. Crappie ranged from 2-12 inches. One fish survey was conducted a week after water temperatures had cooled and crappie had moved to more shallow water, which skewed the long-term data trend. There is a one-meal-per-week consumption advisory for black crappie of all sizes for women and childbearing age due to mercury detection in the flesh. Backwaters, side channels and main channel border areas with submerged brush are the best locations for crappie fishing. The numerous backwater lakes of the LaGrange Pool have historically been excellent crappie waters.

Smallmouth Bass

Fair

Smallmouth bass are collected in lower numbers in the LaGrange Pool compared to largemouth bass. Only two Smallmouth bass were collected in 2025.

Blue Catfish

Improving

No blue catfish were collected in 2025, but densities are increasing adding another potential trophy catfish species to the pool.

White Bass

Very Good

The white bass is a schooling species that is present throughout the main channel of the LaGrange Pool. White bass are a cyclic species that are short lived and have high reproductive spikes during flood years. White bass can be found pool wide congregated at outflows and following schools of shad. White bass collections were below the ten-year average with only 8.9 white bass/hour electrofishing collected in the 2025 survey. This below average catch rate follows a spike in abundance in 2024 from the short spring flood pulse. IDNR Biologists have been receiving an increase in calls from anglers catching hybrid striped bass (white bass x striped bass). There is no creel limit on white or hybrid striped bass measuring less than 17 inches, however white or hybrid striped bass measuring 17 inches or greater have a 3 fish/day creel limit on the Illinois River.

Largemouth Bass

Fair

Largemouth bass historically have been prevalent throughout the LaGrange Pool. Like other sunfish species, they have reproductive spikes during big flood years. Spring flood pulses extend water surface area into the floodplain, which provides suitable habitat for bass to carry out their life history strategies. Extended spring flooding has been lacking over the last several years, which has resulted in poor year class strength. The 2025 fish community survey resulted in the collection of only one largemouth bass. Because extended spring flooding has been absent in recent years, Largemouth Bass stocking will occur in the LaGrange Pool 2026 to supplement year class strength.

Flathead Catfish

Excellent

Flathead catfish are common in the La Grange Pool and trophy-sized fish exceeding 36 inches and 30 pounds can be found. The 2025 fish community survey resulted in the collection of 6.2 flathead catfish/hour electrofishing ranging from 2 - 37 inches weighing up to 29 pounds. A focussed catfish survey will be conducted on the LaGrange Pool in 2026. Fish the deep holes, main channel border near current breaks, and woody debris piles or other structure.

Sauger

Average

Sauger and walleye are most abundant in the upper pools of the Illinois River, but are present in the LaGrange pool. Three sauger ranging in size from 9-15 inches were collected in the 2025 La Grange Pool annual fish survey. They are typically found in deep waters during the day, but search for food in the shallows at night, therefor our daytime electrofishing surveys are not ideal to assess sauger or walleye populations.