Johnson

Johnson Lake is a small, clear water lake located two miles north of Marcell, MN in the Bigfork River watershed. There is one inlet from Forest Lake and Jack the Horse Lake, and one outlet to Rice Lake and ultimately the Rice River. Johnson Lake has suitable habitat to produce moderate populations of Northern Pike and panfish, and has a low-density Walleye population supported by stocking. The lake management plan (LMP) was last revised in 2009. Walleye were considered primary management species because of annual fry stocking. Northern Pike, Black Crappie and Bluegill were considered secondary management species. A standard survey was conducted in 2018 to assess the status of the fish community and the effectiveness of Walleye fry stocking. The Walleye gill-net catch was typical for the lake and lakes with similar habitat. Four year classes were identified with age 4 fish the most frequently sampled. All fish corresponded to stocked years, although nine of the previous ten years were stocked. Sampled Walleye ranged from 15 to 28 inches with an average length of 20 inches. Growth was average; Walleye averaged 16 inches at age 4. Johnson Lake provides anglers the opportunity to catch an occasional Walleye, though they are not abundant. The Northern Pike gill-net catch was average compared to similar lakes and had decreased from the three previous surveys. This is considered an improvement, since Northern Pike size quality is generally better when they occur at lower densities. Northern Pike size structure was still fairly poor; sampled pike ranged from 18 to 29 inches with an average length of 22 inches. Ages 2-8 were represented in the sample, with age 3 and 4 fish the most frequently sampled. Pike averaged 21 inches at age 4. Poor size quality may limit the popularity of the pike fishery. The north central pike zone regulation implemented in 2018 requires anglers to release pike from 22-26 inches, while allowing for more harvest of small pike. It is hoped that this regulation will improve size quality on Johnson Lake. The trap-net catch for Bluegill was the highest on record, but within the typical range for lakes with similar habitat. A trend of increased Bluegill catches has been noted in many area lakes in recent years and is consistent with statewide trends. Size structure was modest. Sampled Bluegill ranged from 3 to 9 inches with an average length of 5 inches. The age distribution suggested frequent but irregular recruitment. Ages 3-10 were represented, with ages 3, 6 and 7 the most frequently sampled. About half the sample was age 6 or older, with average growth. Bluegill averaged 6.5 inches at age 6. Poor size quality may limit the popularity of the Bluegill fishery. Johnson Lake has generally produced a modest crappie fishery. Gill-net catches have typically exceeded trap-net catches over time. The 2018 gill-net catch was typical for the lake and lakes with comparable habitat. The size and age distributions suggested irregular recruitment and a population composed of mostly young fish under age 5. Sampled crappie ranged from 5 to 10 inches. Growth appeared slow; crappie averaged 7.5 inches at age 4. Yellow Perch numbers have been quite variable, but generally above the average for similar lakes. The 2018 gill-net catch for Yellow Perch was the lowest on record and below the typical range for lakes like Johnson. A low perch population is likely a limiting factor for production of gamefish like Northern Pike and Walleye. The Tullibee gill-net catch was typical for Johnson Lake but lower than average compared to lakes with similar habitat. Sampled Tullibee range from 11 to 14 inches. Tullibee are an important prey species in addition to Yellow Perch. Standard test netting is generally not an effective way to evaluate Largemouth Bass. Largemouth have been sampled in low numbers in previous surveys, and catches in 2018 were within the typical range for similar lakes. Targeted spring electrofishing would likely provide better information on the bass population, but it has not been conducted on Johnson. Other species sampled in test nets included Bowfin, Pumpkinseed Sunfish, Rock Bass, White Sucker and Yellow Bullhead. In order to maintain or improve fish and wildlife populations, water quality and habitat must be protected. People often associate water quality problems with large-scale agricultural, forestry, urban development or industrial practices in the watershed. In reality, the impact of land use decisions on one lake lot may be relatively small, yet the cumulative impact of those decisions on many lake lots can result in a significant decline in water quality and habitat. For example, removing shoreline and aquatic vegetation, fertilizing lawns, mowing to the water's edge, installing beach sand blankets, failing septic systems and uncontrolled run-off, all contribute excess nutrients and sediment which degrade water quality and habitat. Understanding these cumulative impacts and taking steps to avoid or minimize them will help to insure our quality fisheries can be enjoyed by future generations.

Johnson Lake has been part of a fisheries research project (Study #635) that is evaluating stocking regimes for walleye in four lake classes. The evaluation included fry, small fingerlings, and three densities of larger fingerlings. As part of the evaluation, special assessments (gill net only) were conducted in 2002, 2004, and 2006, and the 2008 population assessment was also included. Johnson Lake received OTC marked walleye fingerlings in 2001, 2003, and 2005. In 2001, walleye fingerlings rated at 13/pound were stocked at a density of 1 lbs. per littoral acre (LA), in 2003 fingerlings 3.3/pound were stocked at 2lbs./LA, and in 2005 fingerlings 35/pound were stocked at 0.5lbs./LA. The greatest numbers of walleye fingerlings were stocked in 2005, even though the stocking rate was the lowest. The walleye catch rate in 2008 was 1.7/gill net, which was at the lower end of the expected range. This is a modest increase from the 2006 assessment (1.3/net). Lengths ranged from 11-22 inches with a mean of 15 inches. Of the 10 fish sampled in gill nets, nine were aged. Six of these fish were age 3 and had an OTC mark indicating they were stocked. The remaining three were age 8 from the 2000 year class, which was a fry stocked year. The fry in 2000 were not treated with OTC and the contribution from that stocking cannot be determined. Growth was similar to the statewide average. It appears that the small fingerling stocking, even at a low density, was better at establishing a year class in Johnson Lake. Similar to the previous assessment, no fish were sampled from the large fingerling/high density stocking that occurred in 2003. While no fish were sampled from the moderate fingerling density in 2008, one was sampled in 2006, and two were sampled in 2004. Fisheries research staff will analyze the data for all the lakes involved to determine the most effective stocking regime. Northern pike were sampled at the upper end of the expected range. Catch rates from previous assessments tended to be variable with rates at either the high end or low end of the expected range. Lengths ranged from 15-29 inches with a mean of 20 inches. Size structure was poor with only four fish exceeding 24 inches in the sample. Scale and bone analysis indicated six year classes with fish age 2 through 7 present. Growth was similar to the statewide average. Bluegill were sampled at a rate near the middle of the expected range. Previous rates have never been observed within the expected range. Lengths ranged from 3.5-8.7 inches with a mean of 6.1 inches. Black crappie were sampled above the expected range, however most lengths were typically small, eight inches or less. Important prey species like yellow perch and white sucker were sampled within the expected range. Yellow perch were typically small and would not interest most anglers. Tullibee catch rates were lower than expected, yet similar to previous assessments. Other species sampled include black bullhead, bowfin, brown bullhead, one largemouth bass, pumpkinseed sunfish, rock bass, and yellow bullhead.

Johnson Lake has been part of the fisheries research project F-26-R, Study 635, "Evaluation of walleye stocking in 80-400 hectare Minnesota lakes." The objective of the study is to determine which walleye stocking regime is most effective in moderate-sized lakes in Minnesota lake classes 23, 24, 25, and 31. The study specifically evaluated walleye fry, small fingerlings, and three densities of large fingerlings. Johnson Lake received walleye marked with oxytetracycline (OTC) in 2001, 2003 and 2005. Large fingerlings were stocked in 2001 at a rate of l lb/ littoral acre, in 2003 at a rate of 2 lbs/littoral acre, and in 2005 at a rate of 0.5 lbs/littoral acre. The special assessments (gill nets only) conducted in 2004 and 2006 were used to evaluate these stockings. In 2006, the walleye gill-net catch (1.3 fish/net) was within the interquartile range for class 23 lakes. In all previous assessments except 1972 (6.7 fish/net), the walleye gill-net catch varied from 1.0 to 3.3 fish/net. The sampled fish ranged from 10.4 to 24.8 inches and had a mean length of 18.4 inches. Age analysis indicated four age classes were sampled from age 2 to age 7. Mean length-at-age were similar to statewide averages. In this study, it appears the large fingerling stockings were not effective in establishing year classes in Johnson Lake. In 2006, only one fish was collected from any of the marked fingerling stockings. The fish corresponded to the 2001 fingerling stocking (1 lb/littoral acre). In 2004, two fish also corresponded to the 2001 stocking. No fish have been sampled from the highest density of fingerling stockings (2 lbs/littoral acre) that occurred in 2003. No fish from the fall 2005 fingerling stocking were observed in the 2006 assessment, however, this is may be due to how small the fish would be relative to the gill net mesh sizes. Fisheries research staff will be analyzing the data for all lakes involved to determine the most effective stocking regime for these types of lakes.

Based on Minnesota DNR survey data, anglers target Walleye, Rock Bass, Northern Pike, Largemouth Bass, and Bluegill in Johnson. See the full species list above for catch rates, size structure, and quality scores.

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

Johnson has a maximum depth of 51 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Johnson is from 2018. Surveys this old should be treated with some caution — fish populations change over time.

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