Thunder

Thunder (DOW# 77-0066-00; Lake Class 39) is a 214-acre lake located near Browerville, Minnesota. A Minnesota Department of Natural Resources (MNDNR) owned concrete boat ramp is located on the south shore. Thunder has 2.9 miles of shoreline and a maximum depth of 17 feet. The lake is managed primarily for Northern Pike and Walleye and secondarily for Black Crappie. Thunder is in the process of recovering from a winterkill in the winter of 2022-2023. Walleye, Largemouth Bass, and Bluegill are particularly susceptible to winterkills, with Northern Pike, Yellow Perch, and Black Crappie more resistant. This winterkill appears to have affected Walleye and Largemouth Bass most heavily. A total of 21 Northern Pike were captured in 2025 (10.5/gillnet). This catch was slightly below the 2019 (11/gillnet) and 2013 (11.2/gillnet) surveys. Lengths sampled ranged from 16 to 29 inches and averaged 21.7 inches. Only 19 percent measured greater than 24 inches. This value is above that of 2019 (15.9%) and below 2013 (28.9%). The clear presence of large fish suggests significant survival. Anglers are encouraged to take advantage of the current Northern Pike regulation by harvesting small fish and releasing large fish. This can help preserve the fishery and maintain balance in the fish community on Thunder. Seven Walleye were captured in 2025 (3.5/gillnet), which is higher than both 2019 (1.75) and 2013 (2.75). Lengths observed ranged from 11 to 14 inches, with the only year class represented being 2023. Thunder has been stocked with Walleye fry annually since 2016 following the determination that natural reproduction was limited. The lack of fish from year classes prior to 2023 is likely due to the winterkill. Only 5 Black Crappie were sampled in trap nets in 2025 (0.83/trap net). This is within the normal range for this type of lake. Lengths sampled ranged from 6.5 to 8.5 inches, but the limited sample size along with evidence of winterkill survival means quality fish may still be present in Thunder. One juvenile Largemouth Bass measuring 5.4 inches was captured in 2025. Electrofishing in 2024 captured 22 Largemouth Bass ranging in length from 3.7 to 14.4 inches. Though not an actively managed species, quality Largemouth Bass have been observed in prior surveys and their recovery will be monitored. Yellow Perch are an important forage species in Thunder with a few individuals attaining lengths desirable to anglers. A total of 12 Yellow Perch were captured in 2025 (6/gillnet), which is below average for this lake type and below the historical range for Thunder (8 - 27/gillnet). Lengths ranged from 6 to 10.5 inches. Ages collected in 2025 show fish attaining 9 inches by age 4 and fish up to age 5 present. Yellow Perch abundance is influenced heavily by predation and the observed change cannot be attributed solely to winterkill. Bluegill do not appear to have been heavily affected in the winter of 2022-2023. A total of 42 Bluegill were captured in trap nets (7/trap net). Lengths captured ranged from 3.4 to 9.1 inches and averaged 5.6 inches. The 2025 catch rate and average length were similar to the historical range for summer trap nets in Thunder (3.6 - 9.3/trap net; 5.3 - 6.8 inches). Bluegill are not actively managed in Thunder, but fish exceeding 9 inches have been consistently present in surveys. Brown, Black, and Yellow Bullheads were abundant in 2025, with Black Bullheads dominating net catches. Black Bullheads often thrive following a winterkill event and are consistently present in surveys in Thunder. Other fish species observed were Bowfin (Dogfish), Brown Bullhead, Yellow Bullhead, Green Sunfish, Pumpkinseed, and White Sucker.

Minnesota DNR Fisheries IBI program staff conducted an assessment of lakeshore habitat on Thunder Lake on June 09 2020, following the Score the Shore survey protocols. The assessment consisted of 31 survey sites evenly spaced 150 meters around the lake. Assessments were made in three habitat zones: Shoreline Zone (the shore-water interface to the top of the natural bank), Shoreland Zone (land-ward from shoreline to development structure or 100 feet), and Aquatic Zone (lake-ward 50 feet of shoreline). The average lakewide habitat score was 78.1 (±3.9) out of 100 possible. Approximately 41 percent of the sites were developed with a mean score of 62.1 (±7.3), while undeveloped sites had a mean score of 89.6 (±1.0).

Minnesota DNR Fisheries IBI program staff conducted an assessment of lakeshore habitat on Thunder Lake on June 09 2020, following the Score the Shore survey protocols. The assessment consisted of 31 survey sites evenly spaced 150 meters around the lake. Assessments were made in three habitat zones: Shoreline Zone (the shore-water interface to the top of the natural bank), Shoreland Zone (land-ward from shoreline to development structure or 100 feet), and Aquatic Zone (lake-ward 50 feet of shoreline). The average lakewide habitat score was 78.1 (±3.9) out of 100 possible. Approximately 41 percent of the sites were developed with a mean score of 62.1 (±7.3), while undeveloped sites had a mean score of 89.6 (±1.0).

Based on Minnesota DNR survey data, anglers target Northern Pike, Largemouth Bass, Hybrid Sunfish, Rock Bass, and Yellow Perch in Thunder. See the full species list above for catch rates, size structure, and quality scores.

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

Thunder has a maximum depth of 17 feet, per Minnesota DNR data.

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

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