Section Twelve

Section 12 is a 156-acre lake located approximately seven miles southeast of Aitkin. Fifty seven percent of Section 12 is less than 15 feet deep, and the lake has a maximum depth of 40 feet. A public access is located on the northwest corner of the lake. Much of the lake is developed with 24.5 homes or cabins per shoreline mile. Sand is abundant along most of the shoreline, but areas of gravel, detritus, rubble, boulders, and muck are present as well. The aquatic plant community is relatively diverse with 36 species present and is integral to maintaining good water quality and healthy fish populations. Emergent plants such as bulrush are important for shoreline protection, maintaining water quality, and provide essential spawning habitat for bass and panfish species. Submerged plants provide food and cover needed by fish and other aquatic species. A standard survey was conducted the week of 8/25/2025 to assess the fish assemblage. Largemouth Bass electrofishing was conducted as a component of that standard survey on 6/2/2025. Black Crappie relative abundance increased from 15.5 per gill net in 2020 to 27.8 per gill net in 2025. This is well-above the lake class average of 2.2 per net, and it appears this abundance increase has negatively impacted size structure. Average length of Black Crappie captured in 2025 was 7.6 inches and no fish were captured over 9.0 inches. Black Crappie were observed up to 12.0 inches in the previous two surveys when relative abundances were lower. Additionally, growth rates were slower than those observed during the 2020 survey and when compared to county averages, with fish reaching only 6.0 inches at age 4. Northern Pike relative abundance had been relatively stable in all surveys other than 2020 (15.3 per gill net), averaging roughly 5.0 per gill net. The 2025 catch rate returned to levels near this average, at 3.3 per net. Northern Pike ranged from 19.9 to 30.6 inches in length and averaged 24.7 inches. Forty five percent of the Northern Pike captured were 26.0 inches or greater, indicating quality size structure. Largemouth Bass electrofishing catch rates dropped from 44.0 per hour in 2010 to 30.0 per hour in 2025. Additionally, gill net catch rates decreased from 2.7 per net in 2020 to 1.0 per net in 2025. Preferred and memorable-sized Largemouth Bass are present in Section 12, with fish up to 19.5 inches captured in gill nets and 18.9 inches captured while electrofishing. Electrofishing-captured Largemouth Bass averaged 13.0 inches in length. Bluegill relative abundance in 2025 (8.8 per trap net) appeared down from the previous trap net assessment in 2010 (17.5 per trap net) but was still in the normal range when compared to lakes with similar habitat. Bluegill averaged 5.6 inches, with fish up to 8.2 inches observed. Other species observed during this assessment included Bowfin, Brown Bullhead, Yellow Bullhead, and one Walleye. In addition to the standard survey work, IBI (Index of Biotic Integrity) sampling using backpack electrofishing and seining was also conducted in 2025 (Targeted Survey 08/15/2025) to more broadly sample the general fish community and develop a fish-based index of overall lake health. Thirteen nearshore fish species were sampled during the IBI survey including Blackchin Shiner, Bluegill, Central Mudminnow, Green Sunfish, Hybrid Sunfish, Iowa Darter, Johnny Darter, Largemouth Bass, Pumpkinseed, Rock Bass, Tadpole Madtom, Yellow Bullhead, and Yellow Perch.

A targeted survey of nearshore fish species in Section Twelve Lake was conducted on August 15, 2025, by Aitkin area fisheries staff. Sampling sites (N=10) 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 all 10 sampling stations, 3 of which were sampled via boat due to deep water, soft sediment, or dense emergent vegetation. Similarly, a 50-foot seine was used to sample 2 stations, and a 15-foot seine was used at 4 stations. Four stations were not seined due to deep water, soft sediment, or dense emergent vegetation. Nearshore sampling captured 13 species of fish including 3 species that are intolerant of disturbance (e.g., Blackchin Shiner, Iowa Darter, and Rock Bass) and 1 that is tolerant of disturbance (e.g., Green Sunfish). The nearshore data were combined with trap net and gill net data from an 8/25/2025 standard survey to describe the fish community and provide a fish-based score of biotic integrity (FIBI). The FIBI score uses fish community data to quantify a lake's health, and the types of fish species present can help identify 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, Rock Bass), while other species are tolerant of degraded conditions (e.g., Green Sunfish, Common Carp). 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 web site. Results from this survey provide evidence that the fish community in Section Twelve Lake is healthy as indicated by a FIBI score above the general use impairment threshold for aquatic life use determined for similar lakes. These results are similar to previous findings which indicated that Section Twelve Lake is fully supporting aquatic life. These survey results will be considered when the biological health of the lake is assessed during the Mississippi River-Brainerd watershed assessment process, which will be completed in coordination with MN Pollution Control Agency. You can help protect the fish community in Section Twelve Lake by reducing runoff, maintaining natural shorelines, and preventing the spread of invasive species.

Section 12 Lake is located approximately seven miles southeast of Aitkin. The lake is 156 acres with 57% of the lake being less than 15 feet deep and a maximum depth of 40 feet. A public access is located on the northwest corner of the lake. Much of the lake is developed with 24.5 homes/cabins per shoreline mile. Sand is abundant along most of the shoreline, but areas of gravel, detritus, rubble, boulders, and muck are present as well. The aquatic plant community is relatively diverse with 36 species present and is integral to maintaining good water quality as well as maintaining healthy fish populations. Emergent plants such as bulrush are important for shoreline protection, maintaining water quality, and provide essential spawning habitat for bass and panfish species. Submerged plants provide food and cover needed by fish and other aquatic species. DNR staff have observed increasing water clarity since the first survey was conducted in 1973, with each subsequent surveys showing increasingly clear water. This has likely been to the benefit of the aquatic vegetation and the fish species reliant on that vegetation. A standard survey was scheduled for the week of July 13, however due to difficulties related to Covid 19 safety protocols, only gill nets were used to assess the fishery. Black Crappie are the lake's primary management species. Past catches have ranged from 5.8 to 15.5/gill net. The Black Crappie catch showed an increase from the previous survey of 3.2/gill net in 2010, to 15.5/gill net in 2020. This exceeds the management goal of 5.0/gill net by a good margin. The average length of a Crappie was 7.5 inches, with individuals measuring to 12 inches, indicating a potential for quality fish. Northern Pike had showed a fairly stable abundance, but they seem to have spiked since the previous survey, going from 4.5/gill net in 2010, to 15.3/gill net in 2020. The 2020 Northern Pike catch was above the normal range for similar lake types and was the highest observed in survey history. Mean length and weight were 20.4 inches and 1.8 lbs. Most fish were below the protected slot and 15 percent of pike measured between 22 - 26 inches. Only a few individuals were longer than 26 inches. As is the case with many lakes in the area, Largemouth Bass appear to be increasing over time. First sampled in 1990, they have been caught in each survey since, showing another increase from 0.7/gill net in 2010, to 2.7/gill net in 2020. Mean length was about 14 inches, with a mean weight of 1.5 lbs. The largest individual in this survey was 16.5 inches, although fish over 19 inches have been observed in past surveys. Walleye are not stocked in Section 12, but have been present in low numbers in previous surveys ranging from 0.3 to 0.7/gill net. For the first time in survey history no Walleyes were caught in 2020. Recruitment of Walleye had likely been from Section 10 (Wladimiraf) Lake, since suitable spawning habitat is minimal in Section 12 Lake, however, Walleye in Section 10 Lake have also declined in spite of stocking efforts and so the source for Section 12 is no longer viable. Past Yellow Perch catches had been continually increasing from 0.3/gill net in 1973 to a high of 3.5/gill net in 2000, but have since declined to previous levels.

Based on Minnesota DNR survey data, anglers target Largemouth Bass, Northern Pike, Black Crappie, Pumpkinseed, and Rock Bass in Section Twelve. See the full species list above for catch rates, size structure, and quality scores.

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

Section Twelve has a maximum depth of 40 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Section Twelve is from 2025.

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