Gibson Reservoir 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 Gibson Reservoir

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 Gibson Reservoir on the board.

Fishing Gibson Reservoir: what the data says

3,070-acre reservoir in Teton County, Montana. The lake tops out around 165 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.

The drawn water covers 3,070 acres wrapped in 11.2 miles of bank. At index 1.4 the outline is almost a bowl — read the depth changes, not the shoreline. Littoral water — the productive band under ~15 ft — makes up 16% of this chart. Call it 5.1 mi long by 1.3 mi wide at the broadest reach. Teton County claims this one. If the bite dies, Tunnel Lake is 10 mi to the east.

Brook Trout fishing at Gibson Reservoir

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 Main-lake point — point, 7 ft, prime for spring. 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 (7 ft)	Small inline spinner (gold), Tiny spoon
Summer	10 to 30 ft	dawn & dusk	Break off the point (4 ft)	Small spoon fished deep, Trolled lake-clear wobbler + worm
Fall	2 to 15 ft	midday & dawn	Main-lake point (7 ft)	Small spoon (orange), Spinner
Winter	3 to 20 ft	dawn	Break off the point (4 ft)	Small jigging spoon, Tungsten jig + plastic

Arctic Grayling fishing at Gibson Reservoir

Early season arctic grayling use the shallows, holding in 2 to 10 ft. Summer is a 3 to 15 ft game here, winter an 8 to 25 ft one. The chart's best answer is Rock reef — rock pile, 2 ft, prime for spring. Best bite is the evening and early morning. Tie on a dry fly (parachute adams, elk hair caddis) or a small inline spinner and you're in the game.

Season	Depth	Best window	Start at	Go-to baits
Spring	2 to 10 ft	midday & dusk	Rock reef (2 ft)	1/16 oz spinner (silver), Small dry fly (Adams, Griffith's)
Summer	3 to 15 ft	dusk & dawn	Rock reef (2 ft)	Dry fly (parachute Adams, elk hair caddis), Small inline spinner
Fall	6 to 20 ft	midday	Break off the point (4 ft)	Small spoon, Beadhead nymph under indicator
Winter	8 to 25 ft	midday & dawn	Shallow bay flat (8 ft)	Tungsten jig + waxworm, Small jigging spoon (gold)

Cutthroat Trout fishing at Gibson Reservoir

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. Main-lake point is the standout, a point at roughly 7 ft, rated prime for fall 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 (7 ft)	Inline spinner (silver/gold), Small spoon
Summer	10 to 35 ft	dawn & dusk	Break off the point (4 ft)	Trolled spoon (small), Inline spinner
Fall	5 to 25 ft	dawn & dusk	Main-lake point (7 ft)	Casting spoon, Inline spinner
Winter	10 to 40 ft	dawn	Break off the point (4 ft)	Small jigging spoon, Marabou jig

Rainbow Trout fishing at Gibson Reservoir

Spring rainbow trout on Gibson Reservoir 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 Main-lake point first on the milk run — a point near 7 ft that grades prime for spring. 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	Main-lake point (7 ft)	Inline spinner (silver), Small spoon
Summer	8 to 30 ft	dawn & dusk	Break off the point (4 ft)	Dodger + spoon (deep troll), Flutter spoon
Fall	10 to 35 ft	dawn & dusk	Main-lake point (7 ft)	Casting spoon, Jerkbait over shoals
Winter	8 to 40 ft	dawn	Break off the point (4 ft)	Jigging spoon, Tube jig (white)

Notable structure

Structure-wise the chart holds 11 features, led in depth by Deep basin at roughly 159 ft.

Deep basin: deep basin, around 159 ft
Feeding flat: feeding flat, around 43 ft
Feeding flat: feeding flat, around 43 ft
Feeding flat: feeding flat, around 43 ft
Shallow bay flat: feeding flat, around 8 ft
Main-lake point: point, around 7 ft
Secondary point: point, around 5 ft
Back-bay flat: feeding flat, around 5 ft
Feeding flat: feeding flat, around 5 ft
Break off the point: drop-off, around 4 ft
Rock reef: rock pile, around 2 ft

Public access & boat ramps

Boat launch — ramp
Boat launch — ramp

Access data: OpenStreetMap contributors (ODbL) — community-mapped launches. Confirm conditions and fees locally before you launch.

Gibson Reservoir 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 Gibson Reservoir specifically, so confirm the current rules before you fish.

Check the official Montana fishing regulations →

Common questions

How deep is Gibson Reservoir?

Gibson Reservoir is about 165 ft (50 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 Gibson Reservoir?

Anglers target brook trout, arctic grayling, cutthroat trout, rainbow trout on Gibson Reservoir.

Where is the best fishing spot on Gibson Reservoir?

Rock reef is the top-rated area: a rock pile in about 2 ft of water that rates prime for arctic grayling in spring. Every other rated spot, per species and season, is on the map above.

When is the best time to fish Gibson Reservoir?

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 Gibson Reservoir?

Fishing on Gibson Reservoir 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

Tunnel Lake 10 mi · Split Rock Lake 14 mi · Pishkun Reservoir 16 mi · Willow Creek Reservoir 17 mi · Ostle Reservoir 26 mi · Bean Lake 28 mi · Canyon Lake (Lewis and Clark) 31 mi · Camp Lake (Lewis and Clark) 32 mi · Lake Otatsy 32 mi · Parker Lake 32 mi · Lena Lake 32 mi · Heart Lake (Lewis and Clark) 34 mi

See how Gibson Reservoir stacks up: best rainbow trout lakes in Montana · best brook trout lakes in Montana · best arctic grayling lakes in Montana · best cutthroat trout lakes in Montana

More water nearby: Teton County fishing maps (5 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.