Siamese Lake, Upper Depth Map & Fishing Spots (MT)

Hatch outlook

Grasshoppers (east-side summer)Active window

Typical here: Jul 1 – Oct 15 · until the hard frosts of mid-October; on the Missouri, August hoppers fish mid-river, not the banks

adultall day in high summer, best when afternoon wind knocks bugs onto the water

Pulls fish to the windward grassy banks and edges for months — fish the bank the wind blows ONTO.

The friendliest crossover of the summer: on lakes, drift the windward bank with a bubble-and-foam-hopper — the bubble's splash doesn't hurt a hopper presentation. On rivers, the same rig dead-drifted along the undercut grass banks, or small gold spinners under the banks between rises.

The event happens over grassy banks, undercut edges and windward shorelines

Spruce MothActive window

Typical here: Jul 20 – Aug 31 · a conifer-forest event — it needs fir and lodgepole on the banks, so it's a Rock Creek / Blackfoot / upper Bitterroot specialty

adultmorning through midday — moths don't enter the water willingly — landings are sporadic and near the conifer banks; fish the imitation LOW in the film with minimal floatant, even fully drowned, with a little movement

When the moths show, just about every run produces — large trout key on them so hard that one pattern carries the whole box for two weeks.

Honest limit: a small drowned-surface moth has no lure analog. The workable rig is a casting bubble with a drowned moth pattern along the timbered banks in the morning; otherwise fish spinners early and late and leave the moth window to the film.

2–3 weeks at best, and day-to-day — fish key on the moths when they show and vanish with them

The event happens over banks under conifers — the moths rarely reach mid-river

Recommendations come from depth structure and seasonal species behavior. Treat them as a starting point, not a guarantee. Contours here are interpolated from real agency depth surveys (state DNR / USACE). Never use for navigation. Always check local regulations.

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Recent catches at Siamese Lake, Upper

Shared by DepthScout anglers. Exact spots stay private, always.

No shared catches here yet — be the first.Log a catch from the map above and share it to put Siamese Lake, Upper on the board.

Fishing Siamese Lake, Upper: what the data says

25-acre lake in Mineral County, Montana. The lake tops out around 50 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 24 acres, worked by 0.9 miles of shoreline. Nearly circular (index 1.4), so the story is the bottom, not the bank. About 54% of the surface sits shallower than 15 ft — that's the weed-and-bait zone. Call it 0.3 mi long by 0.2 mi wide at the broadest reach. Mineral County claims this one. If the bite dies, Siamese Lake, Lower is 1 mi to the east.

Brook Trout fishing at Siamese Lake, Upper

Early season brook trout use the shallows, holding in 2 to 15 ft. Summer is a 10 to 30 ft game here, winter a 3 to 20 ft one. The chart's best answer is Break off the point — drop-off, 19 ft, prime for summer. Best bite is early morning and the evening. Tie on a small spoon fished deep or a trolled lake-clear wobbler + worm and you're in the game.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 15 ft	dawn & dusk	Main-lake point (6 ft)	Small inline spinner (gold), Tiny spoon
Summer	10 to 30 ft	dawn & dusk	Break off the point (19 ft)	Small spoon fished deep, Trolled lake-clear wobbler + worm
Fall	2 to 15 ft	midday & dawn	Main-lake point (6 ft)	Small spoon (orange), Spinner
Winter	3 to 20 ft	dawn	Break off the point (19 ft)	Small jigging spoon, Tungsten jig + plastic

Cutthroat Trout fishing at Siamese Lake, Upper

In spring, cutthroat trout run shallow here, mostly 3 to 15 ft. Summer pushes them deeper, 10 to 35 ft, and winter fish settle into 10 to 40 ft. Break off the point is the standout, a drop-off at roughly 19 ft, rated prime for summer cutthroat trout. Time it for early morning and the evening. You won't need more than a trolled spoon (small) or an inline spinner most summer days.

Season	Depth	Best window	Start at	Go-to baits
Spring	3 to 15 ft	dawn & dusk	Main-lake point (6 ft)	Inline spinner (silver/gold), Small spoon
Summer	10 to 35 ft	dawn & dusk	Break off the point (19 ft)	Trolled spoon (small), Inline spinner
Fall	5 to 25 ft	dawn & dusk	Main-lake point (6 ft)	Casting spoon, Inline spinner
Winter	10 to 40 ft	dawn	Break off the point (19 ft)	Small jigging spoon, Marabou jig

Notable structure

The chart marks 3 structure features on Siamese Lake, Upper; the deepest is Deep basin at about 50 ft.

Deep basin: deep basin, around 50 ft
Break off the point: drop-off, around 19 ft
Main-lake point: point, around 6 ft

Siamese Lake, Upper fishing regulations

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 Siamese Lake, Upper specifically, so confirm the current rules before you fish.

Check the official Montana fishing regulations →

Common questions

How deep is Siamese Lake, Upper?

Siamese Lake, Upper is about 50 ft (15 m) deep at its deepest point. The depth chart here comes from real state fisheries GPS surveys, so the contours reflect measured depths.

What fish are in Siamese Lake, Upper?

Anglers target brook trout, cutthroat trout on Siamese Lake, Upper.

Where is the best fishing spot on Siamese Lake, Upper?

Break off the point is the top-rated area: a drop-off in about 19 ft of water that rates prime for cutthroat trout in summer. Scroll up to the map for the complete spot list by species and season.

When is the best time to fish Siamese Lake, Upper?

For brook trout, 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.

What are the fishing regulations for Siamese Lake, Upper?

Fishing on Siamese 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.

Nearby waters

Siamese Lake, Lower 1 mi · Crater Lake 5 mi · Trio Lakes 6 mi · Cedar Log Lake, North 6 mi · Pearl Lake 7 mi · Cedar Log Lake, South 7 mi · Hidden Lake (Mineral) 7 mi · French Lake 8 mi · Surveyor Lake 8 mi · Hoodoo Lake 9 mi · Oregon Lake, Middle 16 mi · Bonanza Lake, Upper 19 mi

See how Siamese Lake, Upper stacks up: best brook trout lakes in Montana · best cutthroat trout 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.