Lewis

A targeted survey of nearshore fish species in Lewis Lake was conducted on July 18-20, 2022, by Index of Biological Integrity (IBI) Program staff. Sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where possible. Backpack electrofishing was completed at ten sampling stations, but three stations were sampled from the boat due to site conditions. Similarly, a 50-foot seine was used to sample three stations, a 15-foot seine was used at four stations, and site conditions prevented the use of seines at three stations. Nearshore sampling captured sixteen species of fish including six species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, Least Darter, and Pugnose Shiner) and one that is tolerant of disturbance (i.e., Green Sunfish). A concurrent summer trap net survey was also conducted by IBI Program staff. Nine trap nets were set along the shoreline in locations that encompassed multiple habitat types. Trap net sampling captured eight species of fish, including two that are tolerant of disturbance (i.e., Black Bullhead and Green Sunfish). Bluegill comprised a majority of the catch by number and biomass. The nearshore and trap net data were combined with gill net data from a July 2021 survey to describe the fish community and provide a fish-based IBI (FIBI) score. The FIBI uses fish community data to measure a lake's health, and the types of fish species present can help identify any stressors that may be negatively affecting the lake environment. In Minnesota lakes, certain fish species cannot survive without clean water and a healthy habitat (e.g., Blackchin Shiner, Iowa Darter, and Rock Bass), while other species are tolerant of degraded conditions (e.g., Black Bullhead and Green Sunfish). The FIBI score, composed of several fish community diversity and composition metrics, indicates the overall health of a lake by comparing it to what is expected for a healthy lake. For additional information on the FIBI, search for "lake index of biological integrity" on the mndnr.gov website. Results from this survey indicate that the fish community in Lewis Lake is healthy as indicated by an FIBI score that exceeds the exceptional use threshold determined for similar lakes. These results will be considered when the biological health of the lake is assessed during the Rum River Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency.

Lewis Lake is a 179-acre lake located in Kanabec County. The lake is managed primarily for Largemouth Bass and Northern Pike, with Black Crappie and Bluegill as secondary management species. A population assessment was conducted in 2021 via spring electrofishing for Largemouth Bass and summer trap nets and gill nets. The Northern Pike gill net catch rate was 9.2 fish per net. This catch is above the long-term average of 4.87 fish per net. Mean length of Northern Pike in gill nets was 24.0 inches, with a range of 12.1 to 36.2 inches. Northern Pike were, on average, larger in 2021 than during the previous survey. Yellow Perch have historically fluctuated in abundance in Lewis Lake. The 2021 total catch of 17.6 per gill net was the highest, both in catch rate and total number, in the last nine surveys on the lake, and well above the historic average catch of 5.0 fish per net. The average length of Yellow Perch sampled was 6.4 inches with sizes ranging from 5.6 to 9.5 inches. Based on the 2021 gill net catch of Black Crappie, the abundance was low yet close to the historical average with a catch rate of just 0.8 per net. In addition to the fish caught in gill nets, Black Crappies were also captured in the trap nets at a catch rate of 2.7 fish per net, within normal range. The average size of these fish was 8.3 inches with a length range of 4.9 to 10.6 inches. Trap nets were used to characterize Bluegill abundance and size range. The catch rate was 22.8 per net in 2021, well above the previous survey and the most caught in any survey dating back to 1971. Bluegill sampled in trap nets ranged in size from 3.0 to 8.5 inches with 35 percent of the catch 7 inches or greater. The mean length was 6.1 inches. The Largemouth Bass catch rate increased slightly from the most recent sampling to 81.3 per hour in 2021, the highest catch rate recorded on Lewis Lake. Mean length was 10.5 inches with a length range of 4.7 to 19.0 inches. Overall, the fishing on Lewis Lake for many species should be quite good. There are good numbers of Yellow Perch, Bluegill, Largemouth bass, and Northern Pike based on sampling with gill nets, trap nets, and electrofishing.

Lewis Lake is a 220-acre basin managed primarily for Walleye and Northern Pike. Minnesota lakes managed for fishing are grouped into lake classes based on physical, chemical, and biological similarities. Lewis Lake is assigned to lake class 29. In order to compare the present fish population to others in the lake class and to evaluate management goals, a population assessment was conducted on Lewis Lake in August 2013. The lake's management plan now calls for Walleye fingerling stocking (148 pounds) annually. Long-range management goals are to sustain a moderate Walleye population with a target catch rate of 2.5 per gillnet. The long-range goal for Northern Pike is more trophy oriented with a target weight of 4 pounds. Factors limiting the fishery include a low Yellow Perch forage base and limited spawning habitat for Walleye and Northern Pike. The Yellow Perch abundance remains low. Gillnet catch rates have been 1 per lift or less since 1996. Only 6 Perch were caught in the six gill net sets. Yellow Perch are an important forage base for both Walleye and Northern Pike. Spawning habitat didn't appear limiting with both brush and vegetation present in shallow water areas. The Walleye gillnet catch, 1.3/set, while very similar to the previous assessment, was below both the management goal and lake class 25th percentile. Sampled Walleye ranged in length from 11.1 to 22.2 inches with a 15.7-inch and 1.5 pound mean. Otolith samples assigned Walleyes to five year classes, all associated to stocking years. Half the catch was the apparent result of the 2011 fingerling stocking. These 2-year-old fish averaged 12.5 inches. The lake historically has had a low Northern Pike population dominated by large fish. The catch rate, 4 per gillnet, was below the 25th percentile for the lake class but the management goal for size was met with a 5 pound average. Captured Northerns ranged from 20.8 to 36.3 inches with a 27.3-inch average. Cleithra samples distributed Northerns among eight year classes. Pike ranged in age from 2 to 11 years. Growth was fast until slowing at age eight. Although normal when compared to similar lakes, Black Crappie abundance and size both decreased when compared to the previous two assessments. The combined catch averaged 7.6 inches and a quarter pound. The trap net catch rate for Bluegill was 4.4 per set, the lowest recorded on the lake and below the normal range for the lake class. Unfortunately, there was no compensatory increase in size. Bluegills remain small with a 4.7 inch mean. A quality Largemouth Bass and Northern Pike fishery is present in Lewis Lake. Although they failed to meet management goals, Walleye add a bonus aspect for anglers.

Based on Minnesota DNR survey data, anglers target Largemouth Bass, Northern Pike, Hybrid Sunfish, Yellow Perch, and Walleye in Lewis. See the full species list above for catch rates, size structure, and quality scores.

Minnesota DNR records list public access for Lewis. Check the DNR LakeFinder page for the launch type and directions before you go.

Lewis has a maximum depth of 48 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Lewis is from 2022.

No invasive species are on record for Lewis in Minnesota DNR data. Always clean, drain, and dry your equipment to help keep it that way.