Sign inSign up free Sign inSign up free Sign inSign up freeShared by DepthScout anglers. Exact spots stay private, always.
1,500-acre lake near Dayton. The lake tops out around 40 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. The rest of this page walks each species through its year, using the map's own scoring.
When the water first warms, largemouth bass slide up into 2 to 10 ft. Summer is an 8 to 20 ft game here, winter a 15 to 35 ft one. Start at Break off the point. It's a drop-off holding about 11 ft of water and rates prime come summer. The feeding windows run early morning and the evening. Keep a texas-rigged 10" worm or a deep-diving crankbait rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (1 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (11 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (1 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 15 to 35 ft | midday | Break off the point (11 ft) | Blade bait, Jigging spoon |
Come spring, look for northern pike tight to the bank in 2 to 8 ft. They move out to 8 to 20 ft in summer and finish the year down in 5 to 15 ft. If you only fish one area, make it Break off the point: a drop-off around 11 ft that scores prime in fall. Best bite is early morning and the evening. A bucktail or a weedless spoon over cabbage is the honest summer answer here.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (1 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (11 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (11 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Break off the point (11 ft) | Tip-ups, Large jigging spoon |
Spring kokanee on Lake Mary Ronan hold shallow, usually 10 to 30 ft. By summer they slide out to 12 to 40 ft, and by winter most fish are in 10 to 40 ft. The chart's best answer is Deep basin — deep basin, 40 ft, prime for summer. Prime time lands in early morning. The summer box starts with a dodger + pink/orange squid on downrigger or a kokanee bug + corn.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 30 ft | dawn | Break off the point (11 ft) | Small dodger + squid (pink), Wedding-ring spinner + corn |
| Summer | 12 to 40 ft | dawn | Deep basin (40 ft) | Dodger + pink/orange squid on downrigger, Kokanee bug + corn |
| Fall | 5 to 40 ft | dawn | Deep basin (40 ft) | Dodger + squid (deeper red/purple), Small spoon |
| Winter | 10 to 40 ft | dawn | Deep basin (40 ft) | Small glow jig + corn or maggot, Tiny spoon |
Start shallow in spring: yellow perch sit in 3 to 12 ft that time of year. Warm water sends them out to 10 to 30 ft; cold water stacks them in 15 to 35 ft. Top water on the chart: Break off the point, a drop-off in the 11 ft range, prime in summer. Fish it in early morning and you'll meet the bite. Throw a drop-shot micro plastics or a small spoon tipped with worm until the fish tell you otherwise.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (1 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Break off the point (11 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Break off the point (11 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Deep basin (40 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Spring puts cutthroat trout in skinny water — 3 to 15 ft is the zone. Warm water sends them out to 10 to 35 ft; cold water stacks them in 10 to 40 ft. Break off the point is the standout, a drop-off at roughly 11 ft, rated prime for summer cutthroat trout. Plan around early morning and the evening in the warm months. A trolled spoon (small) or an inline spinner covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 15 ft | dawn & dusk | Break off the point (11 ft) | Inline spinner (silver/gold), Small spoon |
| Summer | 10 to 35 ft | dawn & dusk | Break off the point (11 ft) | Trolled spoon (small), Inline spinner |
| Fall | 5 to 25 ft | dawn & dusk | Break off the point (11 ft) | Casting spoon, Inline spinner |
| Winter | 10 to 40 ft | dawn | Break off the point (11 ft) | Small jigging spoon, Marabou jig |
The spring pattern is a shallow one: pumpkinseed in 1 to 8 ft. As the season builds they drop to 2 to 10 ft, wintering in 6 to 18 ft. Top water on the chart: Shallow bay flat, a weed flat in the 1 ft range, prime in spring. Time it for the evening and early morning. Summer baits: a micro tube or a sponge spider (fly) gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 1 to 8 ft | midday & dusk | Shallow bay flat (1 ft) | Micro jig under a float, Tiny beetle-spin |
| Summer | 2 to 10 ft | dusk & dawn | Shallow bay flat (1 ft) | Micro tube, Sponge spider (fly) |
| Fall | 4 to 14 ft | dusk & dawn | Shallow bay flat (1 ft) | Micro jig + waxworm, Small spoon tipped |
| Winter | 6 to 18 ft | dawn | Shallow feeding flat (20 ft) | Tungsten ice jig + plastic, Tiny spoon |
Lake Mary Ronan also holds rainbow trout (8 to 30 ft in summer), smallmouth bass (10 to 30 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Structure-wise the chart holds 7 features, led in depth by Deep basin at roughly 40 ft.
Access data: OpenStreetMap contributors (ODbL) — community-mapped launches. Confirm conditions and fees locally before you launch.
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 Lake Mary Ronan specifically, so confirm the current rules before you fish.
Check the official Montana fishing regulations →
Lake Mary Ronan is about 40 ft (12 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 largemouth bass, northern pike, kokanee, yellow perch, cutthroat trout, pumpkinseed, rainbow trout, smallmouth bass on Lake Mary Ronan.
Deep basin is the top-rated area: a deep basin in about 40 ft of water that rates prime for kokanee in summer. The map above holds the full rated-spot list for every species and season.
For largemouth bass, the summer bite is best in early morning and the evening. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Lake Mary Ronan 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.
Flathead Lake 11 mi · Rogers Lake 13 mi · Jette Lake 14 mi · Hubbart Reservoir 15 mi · Foy Lake 17 mi · Half Moon Slough 18 mi · Little Bitterroot Lake 19 mi · Horseshoe Lake (Lake) 20 mi · Mccaffery Lake 20 mi · Loon Lake (Lake) 20 mi · Peterson Lake 21 mi · Abbot Lake 21 mi
See how Lake Mary Ronan stacks up: best largemouth bass lakes in Montana · best smallmouth bass lakes in Montana · best northern pike lakes in Montana · best rainbow trout lakes in Montana
More water nearby: Lake County fishing maps (12 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.