Pimushe

Temperature and dissolved oxygen measurements were collected from the deepest basin in Pimushe Lake, which is located partially within the Leech Lake Reservation, on August 7th, 2025, to evaluate the quantity and quality of cold, oxygenated water (oxythermal habitat) available to coldwater fish species such as Cisco, also known as Tullibee, the most sensitive coldwater species present in this lake. During the summer, Cisco require a layer of oxythermal habitat that contains water temperatures below 21.2 degrees C (70.2 degrees F), and dissolved oxygen concentrations above 3.0 mg/L. This layer can be characterized using a single variable, TDO3, the temperature at which dissolved oxygen decreased to 3.0 mg/L. During this survey, TDO3 was 21.6 degrees C (70.9 degrees F), which indicates that oxythermal conditions were unsuitable for coldwater species at the time of the survey. Data collected by the Minnesota Department of Natural Resources during the late summer period of maximum oxythermal stress (July 26th to August 24th) in 2008 indicated unsuitable oxythermal habitat, when the oxythermal habitat layer was not present. However, a survey completed in 2024 did indicate marginal habitat for Cisco, with a TDO3 of 20.5 degrees C. When inadequate oxythermal habitat is available coldwater species are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

A targeted survey of nearshore fish species in Pimushe Lake, which lies partially within the boundaries of the Leech Lake Reservation, was conducted on August 19-20, 2024, 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 all 18 sampling stations, but eight stations were sampled from the boat due to site conditions. Similarly, a 50-foot seine was used to sample seven stations, a 15-foot seine was used to sample four stations, and site conditions (e.g., dense aquatic vegetation and soft substrate) prevented the use of a seine at seven stations. Nearshore sampling captured 16 species of fish including four species that are intolerant of disturbance (i.e., Blackchin Shiner, Blacknose Shiner, Iowa Darter, and Rock Bass) and one species that is tolerant of disturbance (i.e., Fathead Minnow). The nearshore data was combined with gill net and trap net data from a July 2022 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, Fathead Minnow, 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. Temperature and dissolved oxygen measurements were also collected from the deepest basin in Pimushe Lake on August 19th, 2024, to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Cisco, also known as Tullibee, the most sensitive coldwater species present in this lake. During the summer, Cisco require a layer of oxythermal habitat that contains water temperatures below 21.2 degrees C (70.2 degrees F) and dissolved oxygen concentrations above 3.0 mg/L. Based on the profile from the deepest basin, the water temperature decreased below 21.2 degrees C (70.2 degrees F) at 18.5 feet and the dissolved oxygen concentration decreased to 3.0 mg/L at 21.8 feet at the time of sampling. The thickness of this layer of water in the water column was 3.2 feet, indicating that oxythermal habitat was present for Cisco. Further, the temperature at which dissolved oxygen decreased to 3.0 mg/L (i.e., TDO3, a single variable to characterize oxythermal habitat) was 20.5 degrees C (68.9 degrees F). TDO3 values cooler than 21.2 degrees C (70.2 degrees F) indicate that oxythermal conditions were suitable for Cisco at the time of the survey. Data collected by the Minnesota DNR during the late summer period of maximum oxythermal stress in 2008 indicates unsuitable oxythermal habitat at the time of that survey. When inadequate oxythermal habitat is available, Cisco are squeezed into unfavorable, warmer water conditions and experience higher levels of stress. The FIBI and oxythermal habitat survey results will be considered when the biological health of the lake is assessed during the Mississippi River-Headwaters Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency. You can help protect the fish community in Pimushe Lake by reducing runoff and maintaining natural shorelines.

Pimushe Lake is a 1,230-acre lake located 5 miles north of Pennington in Beltrami County. There is a U.S. Forest Service public water access with a concrete ramp and parking for 8 vehicles located on the east shore of the lake off of State Highway 39 (Scenic Highway). Pimushe is managed for Bluegill, Black Crappie, Walleye, Northern Pike and Largemouth Bass. A special regulation for Bluegill consisting of a 5-fish daily possession limit is in effect. Statewide regulations apply to all other species. Pimushe Lake has been known as a quality Bluegill fishery since the 1980s. The 2022 survey results show that the lake's Bluegill population has continued to maintain a quality size structure with a good average size and fish approaching 10 inches in length captured. The special Bluegill regulation in effect since 2014 has proven to be an effective tool at limiting harvest and maintaining a high-quality Bluegill population. While Black Crappie may receive far less attention from Pimushe's anglers than Bluegill, they are nevertheless worth pursuing. Catch rates for Black Crappie were above historical averages in 2022. Similar to Bluegill, Black Crappie had a good average size with some fish approaching 13 inches in length. Age data from the catch showed a healthy number of year classes present indicating that the population is sustaining itself nicely. Walleye numbers have been fairly consistent over the course of historical surveys however the 2022 catch rate (3.42/GN) was the highest recorded since 1999. The lake's Walleye population has relied on natural reproduction within the lake as well as fish migration from the connected waters of the Turtle River and Cass Lake. Walleye had an average size of over 13 inches in length, with fish up to 21 inches captured in this survey. A large proportion of the walleye catch was comprised of younger fish ages 1-3 which holds promise for good Walleye fishing over the next few years as these fish grow to acceptable sizes for anglers. Northern Pike are commonly caught by anglers fishing Pimushe. The number of pike captured increased considerably from the most recent survey (2017) with a slight decline in average size. Northern Pike up to 31 inches were captured in this survey. Although Largemouth Bass were not targeted as a part of this survey, previous survey results for bass depict a moderate density population with some large individuals present. Similar to many lakes in the area, Pimushe contains abundant habitat for the species and plenty of options for bass anglers. Other species captured in this survey were Bowfin, Brown Bullhead, Hybrid Sunfish, Pumpkinseed Sunfish, Rock Bass, Tullibee Cisco, Yellow Bullhead, White Sucker and Yellow Perch. Pimushe Lake is infested with zebra mussels and the aquatic plant, starry stonewort. Both are aquatic invasive species (AIS). AIS can be transferred by anglers and boats from infested to non-infested waterbodies. To avoid spreading AIS, lake users are required to remove all aquatic plants and animals from their watercraft and drain all water from their boat before leaving the access. Please follow the current AIS regulations to avoid spreading to other lakes.

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

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

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

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

Yes — Pimushe has confirmed starry stonewort and zebra mussel. Clean, drain, and dry your equipment to avoid spreading invasives to other waters.