Jasper

Temperature and dissolved oxygen measurements were collected in the deepest basin in Jasper Lake, on August 6, 2024, 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 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, the water temperature dropped below 8.8 degrees C (47.8 degrees F) at 36.4 feet, and the dissolved oxygen concentration never decreased to 3.0 mg/L at the time of sampling. The thickness of this layer in the water column was 55.4 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 the dissolved oxygen remained above 3.0 mg/L throughout the sampled depths. The temperature at the bottom of the lake was 5.8 degrees C (42.4 degrees F). Instances in which the dissolved oxygen does not reach below 3.0 mg/L and temperature remains below 8.8 degrees C, indicate that oxythermal conditions were suitable for Lake Trout at the time of the survey. Data collected by the Minnesota Department of Natural Resources in 1972 and 1992 during the late summer thermal stress period indicate suitable oxythermal habitat in years surveyed, with the least favorable conditions recorded in 1992, when the suitable habitat layer thickness was 29.9 feet. When inadequate oxythermal habitat is available, Lake Trout are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

Temperature and dissolved oxygen measurements were collected in the deepest basin in Jasper Lake, on August 6, 2024, 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 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, the water temperature dropped below 8.8 degrees C (47.8 degrees F) at 36.4 feet, and the dissolved oxygen concentration never decreased to 3.0 mg/L at the time of sampling. The thickness of this layer in the water column was 55.4 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 the dissolved oxygen remained above 3.0 mg/L throughout the sampled depths. The temperature at the bottom of the lake was 5.8 degrees C (42.4 degrees F). Instances in which the dissolved oxygen does not reach below 3.0 mg/L and temperature remains below 8.8 degrees C, indicate that oxythermal conditions were suitable for Lake Trout at the time of the survey. Data collected by the Minnesota Department of Natural Resources in 1972 and 1992 during the late summer thermal stress period indicate suitable oxythermal habitat in years surveyed, with the least favorable conditions recorded in 1992, when the suitable habitat layer thickness was 29.9 feet. When inadequate oxythermal habitat is available, Lake Trout are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

Temperature and dissolved oxygen measurements were collected in the deepest basin in Jasper Lake, on August 6, 2024, 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 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, the water temperature dropped below 8.8 degrees C (47.8 degrees F) at 36.4 feet, and the dissolved oxygen concentration never decreased to 3.0 mg/L at the time of sampling. The thickness of this layer in the water column was 55.4 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 the dissolved oxygen remained above 3.0 mg/L throughout the sampled depths. The temperature at the bottom of the lake was 5.8 degrees C (42.4 degrees F). Instances in which the dissolved oxygen does not reach below 3.0 mg/L and temperature remains below 8.8 degrees C, indicate that oxythermal conditions were suitable for Lake Trout at the time of the survey. Data collected by the Minnesota Department of Natural Resources in 1972 and 1992 during the late summer thermal stress period indicate suitable oxythermal habitat in years surveyed, with the least favorable conditions recorded in 1992, when the suitable habitat layer thickness was 29.9 feet. When inadequate oxythermal habitat is available, Lake Trout are squeezed into unfavorable, warmer water conditions and experience higher levels of stress.

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

Jasper has a maximum depth of 125 feet and a mean depth of 31 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Jasper is from 1992. Surveys this old should be treated with some caution — fish populations change over time.

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

No — Jasper has no lake-specific regulations in the 2026 Minnesota DNR regulations, so statewide Minnesota limits apply. The statewide walleye and sauger limit is: 6 combined, not more than one walleye over 20". Verify current rules with the Minnesota DNR before keeping fish.