Anderson Lake

Description

Anderson Lake is a natural bottomland impoundment adjoining the Illinois River in the southeast corner of Fulton County. It is situated on the west floodplain of the river, and the Anderson Lake Conservation Area encompasses 2,133 acres and is maintained as a public fishing and hunting site. A levee was constructed in 1980 to facilitate waterfowl management. It separates Anderson Lake, which is 1,132 surface acres from Carlson Lake, which is 231 surface acres. Anderson Lake is a typical Illinois River backwater lake that is connected annually to the main stem of the river. The 9.1 mile gently sloping shoreline is bordered by button bush and bottomland forest. It is shallow, with a maximum depth of 5 feet at the spillway crest. The bottom substrate is a flocculent mud and the water clarity is usually turbid. The submerged rooted aquatic plants have been very limited since the late 1950s.

Fishery History

Due to the annual inundation of Anderson Lake by the Illinois River, fish species management on this small scale is a difficult objective. The associated sedimentation, loss of lake water volume and loss of aquatic plants have all negatively impacted the sport fish habitat present in Anderson Lake. However, annual documentation of the sport fish populations are very important in our understanding of how these backwater lakes function with the Illinois river. Anderson Lake is annually sampled in the fall utilizing D.C. boat electrofishing. The current fishery was maintaining a cyclic pulse of sport fish with positive impacts from the flood years of 1993-95 and then high water in 1998 and 1999 and then high spring through summer levels in 2008-2011. In 2012, the very low water levels with the drought had negative impacts on the fishery in Anderson Lake. Multiple low oxygen fish kills occurred in late August through September. The majority of the biomass of fish killed were the Asian carp species. The recent improved sportfishery of the Illinois river is due to water quality improvements, and now habitat improvements in the backwater lakes could assist the aquatic life. However, the very recent introductions of the silver and Bighead Carp have added more negative nonnative species to the river ecosystem. These new nonnatives will need to be monitored for their impact on the fish community of the backwater lakes. In 2019 and 2020, the Largemouth Bass, Bluegill and White Crappie populations showed a substantial increase in their population densities. This appears to again be related to the high water levels and recruitment from 2018. And the fish species diversity was also very high at 32 in 2019 and 20 in 2020. The timing and duration of the typical high water level entry from the Illinois river into Anderson Lake may influence the sport fish density each year and the anglers success. However, the current lack of depth and the high load of loose sediment in Anderson Lake appears to have made the habitat inhospitable for sport fish survival.

Site Regulations

Commercial Fish Harvest — Commercial species are annually harvested under the contract system by individual fishermen. Activity periods are set by the site supervisor and district resource managers and are scheduled so as not to conflict with sport fishing or waterfowl hunting. During the fall 2013 commercial harvest, 49631 total pounds were removed. The Asian carp population has dramatically increased in the Illinois River and their full impact on the system is not known, but it is anticipated to be very negative on native species. The increase in competition for space and food at the bottom of the food chain will not help the sport fish populations in the backwater lakes of the Illinois river. Sport fishing seasons and limits are uniform with statewide rules. However, during the waterfowl hunting season, boat fishing (electric motors only) is only allowed in a designated area near the boat ramp and fish attractors. Largemouth and Smallmouth Bass have a 12-inch minimum size limit on the Illinois river and all backwaters.

Site-Specific Fishing Regulations:

• Recreational Use Restrictions:  Waterfowl Refuge or Hunting Area (see above)
• Large or Smallmouth Bass: 12 inch Minimum Length Limit; 6 Fish Daily Harvest Limit

Additional Information

Planning to eat your catch?  Fish Consumption Advisory information can be found here: Fish Consumption Advisory Page

Bath Map: Anderson Lake