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14-acre lake in Mineral County, Montana. The lake tops out around 80 ft. The depth chart is built from real state fisheries GPS surveys, so the humps, channels and drop-offs you see are measured, not guessed. What the data behind the map says about each species, season by season:
The outline encloses 16 acres, worked by 0.6 miles of shoreline. At index 1.1 the outline is almost a bowl — read the depth changes, not the shoreline. Roughly 9% of the water is 15 ft or less, the band where the food chain lives. Mineral County claims this one. If the bite dies, Lost Lake (Mineral) is 1 mi to the northeast.
In spring, walleye run shallow here, mostly 4 to 15 ft. Summer pushes them deeper, 15 to 35 ft, and winter fish settle into 20 to 40 ft. Shoreline break is the standout, a drop-off at roughly 24 ft, rated prime for fall walleye. Time it for the evening and early morning. You won't need more than a crawler harness on bottom bouncer or a deep crankbait (trolled) most summer days.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | open water | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Shoreline break (24 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 12 to 40 ft | dusk & night | Shoreline break (24 ft) | Jigging rap, Jig + big minnow |
| Winter | 20 to 40 ft | dusk & dawn | Shoreline break (24 ft) | Jigging spoon + minnow head, Rattle bait |
When the water first warms, northern pike slide up into 2 to 8 ft. By summer they slide out to 8 to 20 ft, and by winter most fish are in 5 to 15 ft. If you only fish one area, make it Shallow bay flat: a feeding flat around 5 ft that scores prime in spring. In summer the feeding windows fall in early morning and the evening. Keep a bucktail or a weedless spoon over cabbage rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (5 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Shallow bay flat (5 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Shallow bay flat (5 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (5 ft) | Tip-ups, Large jigging spoon |
The spring pattern is a shallow one: yellow perch in 3 to 12 ft. As the season builds they drop to 10 to 30 ft, wintering in 15 to 35 ft. Top water on the chart: Shoreline break, a drop-off in the 24 ft range, prime in summer. Time it for early morning. Summer baits: a drop-shot micro plastics or a small spoon tipped with worm gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (5 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Shoreline break (24 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Shoreline break (24 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Shoreline break (24 ft) | Tungsten jig + spikes, Rattle spoon (small) |
When the water first warms, smallmouth bass slide up into 3 to 12 ft. By summer they slide out to 10 to 30 ft, and by winter most fish are in 20 to 45 ft. If you only fish one area, make it Shoreline break: a drop-off around 24 ft that scores prime in winter. In summer the feeding windows fall in early morning and the evening. Keep a drop shot (goby/minnow) or a ned rig rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | open water | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Shoreline break (24 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Shoreline break (24 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Shoreline break (24 ft) | Blade bait, Hair jig |
Spring rainbow trout on Bonanza Lake, Upper hold shallow, usually 5 to 20 ft. They move out to 8 to 30 ft in summer and finish the year down in 8 to 40 ft. Put Shoreline break first on the milk run — a drop-off near 24 ft that grades prime for winter. The feeding windows run early morning and the evening. The summer box starts with a dodger + spoon (deep troll) or a flutter spoon.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 5 to 20 ft | dawn & dusk | Shallow bay flat (5 ft) | Inline spinner (silver), Small spoon |
| Summer | 8 to 30 ft | dawn & dusk | Shoreline break (24 ft) | Dodger + spoon (deep troll), Flutter spoon |
| Fall | 10 to 35 ft | dawn & dusk | Shoreline break (24 ft) | Casting spoon, Jerkbait over shoals |
| Winter | 8 to 40 ft | dawn | Shoreline break (24 ft) | Jigging spoon, Tube jig (white) |
When the water first warms, lake trout slide up into 10 to 40 ft. Summer is a 24 to 80 ft game here, winter a 20 to 80 ft one. Start at Deep basin. It's a deep basin holding about 80 ft of water and rates prime come summer. The feeding windows run early morning. Keep a white tube jig (deep) or a magnum spoon on downrigger rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Shoreline break (24 ft) | Casting spoon over shoals, Jerkbait (shallow) |
| Summer | 24 to 80 ft | dawn | Deep basin (80 ft) | White tube jig (deep), Magnum spoon on downrigger |
| Fall | 10 to 50 ft | dusk & dawn | Shoreline break (24 ft) | Heavy casting spoon, Jigging rap over reefs |
| Winter | 20 to 80 ft | dawn | Deep basin (80 ft) | White tube jig, Airplane jig |
Bonanza Lake, Upper also holds crappie (10 to 25 ft in summer), channel catfish (8 to 25 ft in summer). Pick any of them on the map above for rated spots and bait picks.
3 pieces of structure are mapped here — Deep basin, around 80 ft, is the deepest of them.
Season dates, license requirements, and size and bag limits for Montana waters are set by the Montana Fish, Wildlife & Parks — and special regulations can apply to Bonanza Lake, Upper specifically, so confirm the current rules before you fish.
Check the official Montana fishing regulations →
Bonanza Lake, Upper is about 80 ft (24 m) deep at its deepest point. The depth chart here comes from real state fisheries GPS surveys, so the contours reflect measured depths.
Anglers target walleye, northern pike, yellow perch, smallmouth bass, rainbow trout, lake trout, crappie, channel catfish on Bonanza Lake, Upper. This isn't a survey of the water — none is published for it — but an informed estimate from the species common to the region, narrowed by this water's depth, size and each species' range.
Shoreline break is the top-rated area: a drop-off in about 24 ft of water that rates prime for walleye in fall. The interactive chart above rates every spot for each species and season.
For walleye, the summer bite is best in the evening and early morning. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Bonanza Lake, Upper is regulated by the Montana Fish, Wildlife & Parks. Check the official Montana regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Lost Lake (Mineral) 1 mi · Oregon Lake, Middle 3 mi · Cliff Lake (Mineral) 4 mi · Diamond Lake (Mineral) 4 mi · Moore Lake (Mineral) 8 mi · Hoodoo Lake 10 mi · Hidden Lake (Mineral) 13 mi · French Lake 13 mi · Pearl Lake 13 mi · Trio Lakes 14 mi · Crater Lake 17 mi · Siamese Lake, Upper 19 mi
See how Bonanza Lake, Upper stacks up: best smallmouth bass lakes in Montana · best walleye lakes in Montana · best northern pike lakes in Montana · best crappie lakes in Montana
More water nearby: Mineral County fishing maps (19 charts). Browse all Montana fishing maps or see every water on DepthScout. Bathymetry credit: state fisheries survey programs. How we build these maps. Fish here with a sonar unit that logs? Send us your depth data and we'll improve this chart, credited to you. For fishing guidance only, never navigation.