Minnesota · ranked from DNR surveys
Best largemouth bass lakes in Cass County
171 surveyed largemouth bass lakes sit in Cass County; 74 cleared this site's grade rubric, which reads DNR survey catch rates, size structure and trophy history the same way the live map does for every lake. The top 10 are ranked here.
Gull Lake leads at grade A+, with 66.3 largemouth bass per hour of electrofishing in its 2025 survey and a 19-inch fish the biggest measured. Leech Lake is next at A, 20.7 largemouth bass per hour of electrofishing in its 2025 survey, 8% of the largemouth bass netted over 15 inches. Thunder Lake rounds out the top three at A−, a 18-inch fish the biggest measured.
| # | 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 this site's rubric over Minnesota DNR survey data (catch per unit effort against DNR benchmarks, size structure, trophy history). See any lake's page for the underlying numbers. Survey years vary by lake; the table shows each lake's latest.