Minnesota · ranked from DNR surveys
Best largemouth bass lakes in Cass County
The DNR has surveyed largemouth bass in 171 lakes in Cass County. Of those, 74 earn a grade on this site, and the top 10 are ranked below. Grades come from survey catch rates, fish size and trophy history, scored the same way for every lake on the live map.
Gull Lake is first at A+. The DNR caught 66.3 largemouth bass per hour of electrofishing in the 2025 survey, and the biggest was 19 inches. Leech Lake is second at A, with 20.7 largemouth bass per hour of electrofishing in the 2025 survey, and 8% of its largemouth bass measured over 15 inches. Thunder Lake is third at A−, and its biggest largemouth bass was 18 inches.
| # | Lake | Grade | Acres | Survey catch rate | Over 15" | Biggest Surveyed | Avg wt | Surveyed |
|---|---|---|---|---|---|---|---|---|
| 1 | Gull Lake | A+ | 10,010 | 66.3/hr in electrofishing | 24% | 19" | 1.1 lb | 2025 |
| 2 | Leech Lake | A | 103,444 | 20.7/hr in electrofishing | 8% | 19" | 0.5 lb | 2025 |
| 3 | Thunder Lake | A− | 1,347 | 38.8/hr in electrofishing | 47% | 18" | 1.3 lb | 2025 |
| 4 | Roosevelt Lake | A− | 1,511 | 48.9/hr in electrofishing | 12% | 17" | 1.1 lb | 2024 |
| 5 | Webb Lake | A− | 720 | 99.3/hr in electrofishing | 5% | 16" | 0.7 lb | 2025 |
| 6 | Blackwater Lake | A− | 772 | 59.9/hr in electrofishing | 10% | 17" | 0.7 lb | 2023 |
| 7 | Woman Lake | B+ | 5,520 | 12.1/hr in electrofishing | 18% | 20" | 1.4 lb | 2025 |
| 8 | Thirteen Lake | B+ | 555 | 66.3/hr in electrofishing | 8% | 16" | 0.9 lb | 2025 |
| 9 | Mule Lake | B+ | 525 | 49.2/hr in electrofishing | 21% | 16" | 0.8 lb | 2023 |
| 10 | Spider Lake | B+ | 145 | 74.1/hr in electrofishing | 12% | 22" | 1.3 lb | 2017 |
Also ranked in Cass County: Walleye · Northern pike · Muskellunge · Smallmouth bass · Crappie · Bluegill · Yellow perch
All of Minnesota: Best largemouth bass lakes in Minnesota
Grades are based on Minnesota DNR survey data: how many fish the DNR caught (scaled by lake size), how many reached quality size, and the biggest fish measured. Each lake's page has the numbers behind its grade. The table shows each lake's most recent survey year.