Whitefish

A targeted survey of nearshore fish species in Whitefish Lake, which is located partially within the Mille Lac Nation, was conducted on June 30-July 2, 2025, by Lake Biological Monitoring and Assessment Program (LBMA). 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 14 sampling stations. Similarly, a 50-foot seine was used to sample seven stations, and a 15-foot seine was used at five stations. Two stations were not seined due to dense vegetation, detritus, and soft substrate made traversing difficult. Nearshore sampling captured 18 species of fish including five species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, and Rock Bass) and one species that are tolerant of disturbance (i.e., Green Sunfish). A concurrent summer trap net and gill net survey was also conducted by LBMA staff. Nine trap nets were set along the shoreline in locations that encompassed multiple habitat types. Trap net sampling captured eleven species of fish. Bluegill comprised a majority of the catch by number, whereas Bowfin and Bluegill comprised the trap net majority by biomass. The trap net catch was relatively light overall. Nine gill nets were set in deeper locations that encompassed multiple habitat types. Gill net sampling captured 13 species of fish, including two that are intolerant of disturbance (i.e., Cisco and Rock Bass) and one species that is tolerant of disturbance (i.e., Black Bullhead). Northern Pike comprised the gill net majority by biomass, followed by Cisco and Largemouth Bass. The nearshore, trap net, and gill net data were used 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., Green Sunfish and 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 website. Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Whitefish Lake on July 31st, 2025, 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 (maximum sampled depth 57.1 feet), the water temperature decreased below 21.2 degrees C (70.2 degrees F) at 16.4 feet and the dissolved oxygen concentration decreased to 3.0 mg/L at 15.2 feet at the time of sampling. Therefore, the water column did not contain a layer of water with sufficient temperature and dissolved oxygen 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 22.4 degrees C (72.3 degrees F). TDO3 values warmer than 21.2 degrees C (70.2 degrees F) indicate that oxythermal conditions were unsuitable for Cisco at the time of the survey. Data collected by the Minnesota Department of Natural Resources during the window of maximum oxythermal stress (July 26th to Aug 24th) in 2023 and 2024 indicate suitable but limited habitat.The least favorable conditions were recorded in 2025. 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 Rum River Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency. You can help protect the fish community in Whitefish Lake by reducing runoff, maintaining natural shorelines, and preventing the spread of invasive species.

Temperature and dissolved oxygen profiles were collected in the deepest basin in Whitefish (Little Whitefish) Lake on August 9, 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. 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 was below 21.2 degrees C (70.2 degrees F) at the surface (0.0 feet) and the dissolved oxygen concentration decreased to 3.0 mg/L at 21.5 feet at the time of sampling. The thickness of this layer of water in the water column was 21.5 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 19.9 degrees C (67.7 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 this survey. Data collected by the Minnesota Department of Natural Resources in 2023 during the late summer thermal stress period, also indicated suitable oxythermal habitat. When inadequate oxythermal habitat is available, Cisco are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

Temperature and dissolved oxygen profiles were collected in the deepest basin in Whitefish (Little Whitefish) Lake on August 9, 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. 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 was below 21.2 degrees C (70.2 degrees F) at the surface (0.0 feet) and the dissolved oxygen concentration decreased to 3.0 mg/L at 21.5 feet at the time of sampling. The thickness of this layer of water in the water column was 21.5 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 19.9 degrees C (67.7 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 this survey. Data collected by the Minnesota Department of Natural Resources in 2023 during the late summer thermal stress period, also indicated suitable oxythermal habitat. When inadequate oxythermal habitat is available, Cisco are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

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

We don't have a confirmed public access point on record for Whitefish. Check the DNR LakeFinder page for current access details before you go.

Whitefish has a maximum depth of 62 feet, per Minnesota DNR data.

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

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