Knife

Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Knife Lake on August 14th, 2025, to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Trout, the most sensitive coldwater species present in this lake (Lake Whitefish and Cisco, also known as 'Tullibee', are also present). During the summer, Lake Trout require a layer of oxythermal habitat that contains water temperatures below 8.8 degrees C (47.8 degrees F) and dissolved oxygen concentrations above 3.0 mg/L. Based on the profile from the deepest basin (maximum sampled depth 108.2 feet), the water temperature decreased below 8.8 degrees C (47.8 degrees F) at 38.9 feet and the dissolved oxygen concentration stayed greater than 3.0 mg/L at 108.2 feet at the time of sampling. The thickness of this layer of water in the water column was 69.3 feet, indicating that oxythermal habitat was present for Lake Trout. Further, the temperature at which dissolved oxygen decreased to 3.0 mg/L (i.e., TDO3, a single variable to characterize oxythermal habitat) was never reached because dissolved oxygen remained above 3.0 mg/L throughout the sampled depths. In this case, the minimum temperature, 6.1 degrees C (43.0 degrees F), was substituted as TDO3. TDO3 values cooler than 8.8 degrees C (47.8 degrees F) indicate that oxythermal conditions were suitable for Lake Trout 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 Aug 24th) in 2024 also indicates suitable oxythermal habitat. When adequate oxythermal habitat is unavailable, Lake Trout are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Knife Lake on August 14th, 2025, to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Trout, the most sensitive coldwater species present in this lake (Lake Whitefish and Cisco, also known as 'Tullibee', are also present). During the summer, Lake Trout require a layer of oxythermal habitat that contains water temperatures below 8.8 degrees C (47.8 degrees F) and dissolved oxygen concentrations above 3.0 mg/L. Based on the profile from the deepest basin (maximum sampled depth 108.2 feet), the water temperature decreased below 8.8 degrees C (47.8 degrees F) at 38.9 feet and the dissolved oxygen concentration stayed greater than 3.0 mg/L at 108.2 feet at the time of sampling. The thickness of this layer of water in the water column was 69.3 feet, indicating that oxythermal habitat was present for Lake Trout. Further, the temperature at which dissolved oxygen decreased to 3.0 mg/L (i.e., TDO3, a single variable to characterize oxythermal habitat) was never reached because dissolved oxygen remained above 3.0 mg/L throughout the sampled depths. In this case, the minimum temperature, 6.1 degrees C (43.0 degrees F), was substituted as TDO3. TDO3 values cooler than 8.8 degrees C (47.8 degrees F) indicate that oxythermal conditions were suitable for Lake Trout 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 Aug 24th) in 2024 also indicates suitable oxythermal habitat. When adequate oxythermal habitat is unavailable, Lake Trout are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

Temperature and dissolved oxygen (DO) measurements were collected from the deepest basin in Knife Lake on August 14th, 2025, to evaluate the quantity and quality of cold, oxygenated water (i.e., oxythermal habitat) available to Lake Trout, the most sensitive coldwater species present in this lake (Lake Whitefish and Cisco, also known as 'Tullibee', are also present). During the summer, Lake Trout require a layer of oxythermal habitat that contains water temperatures below 8.8 degrees C (47.8 degrees F) and dissolved oxygen concentrations above 3.0 mg/L. Based on the profile from the deepest basin (maximum sampled depth 108.2 feet), the water temperature decreased below 8.8 degrees C (47.8 degrees F) at 38.9 feet and the dissolved oxygen concentration stayed greater than 3.0 mg/L at 108.2 feet at the time of sampling. The thickness of this layer of water in the water column was 69.3 feet, indicating that oxythermal habitat was present for Lake Trout. Further, the temperature at which dissolved oxygen decreased to 3.0 mg/L (i.e., TDO3, a single variable to characterize oxythermal habitat) was never reached because dissolved oxygen remained above 3.0 mg/L throughout the sampled depths. In this case, the minimum temperature, 6.1 degrees C (43.0 degrees F), was substituted as TDO3. TDO3 values cooler than 8.8 degrees C (47.8 degrees F) indicate that oxythermal conditions were suitable for Lake Trout 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 Aug 24th) in 2024 also indicates suitable oxythermal habitat. When adequate oxythermal habitat is unavailable, Lake Trout are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

Based on Minnesota DNR survey data, anglers target Northern Pike, Lake Trout, Walleye, Smallmouth Bass, and Yellow Perch in Knife. 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 Knife. Check the DNR LakeFinder page for current access details before you go.

Knife has a maximum depth of 179 feet and a mean depth of 65 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Knife is from 2017. Surveys this old should be treated with some caution — fish populations change over time.

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