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1,019-acre lake in Algoma District, Ontario. The lake tops out around 50 ft. The depth chart comes from Ontario Ministry of Natural Resources and Forestry bathymetric survey data, so the contours are survey-derived rather than computer-modeled. The depth data here comes from the Ontario MNRF survey of 1970, a decades-old survey (a transect sounding survey). Every species below gets its seasonal read from the same numbers driving the chart.
Usnac Lake maps at 1,023 acres behind 15.9 miles of shoreline — 3 islands included. The 3.6 development index tells the story — a convoluted bank whose fishable edge far outruns the acreage. Littoral water — the productive band under ~15 ft — makes up 73% of this chart. The basin spans about 4.4 mi end to end and 1.1 mi across at its widest. It sits in Algoma District. Its nearest charted neighbour, Radisson Lake, is 4 mi to the southwest.
These fish are listed in an exact-water agency record as forage or ecological context. They are not target-species profiles and do not affect DepthScout's Prime, Good, or Fair spot ratings.
Official Ontario MNRF Fish ON-Line record. The listing documents source-recorded presence, not present abundance or guaranteed catchability.
In spring, lake whitefish run shallow here, mostly 15 to 45 ft. Summer pushes them deeper, 15 to 50 ft, and winter fish settle into 15 to 50 ft. Deep basin is the standout, a deep basin at roughly 50 ft, rated prime for summer lake whitefish. Time it for early morning. You won't need more than a blade bait vertical or a small jigging spoon most summer days.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 15 to 45 ft | midday & dawn | Break off the point (20 ft) | Small jig + waxworm, Blade bait (small) |
| Summer | 15 to 50 ft chart-limited; documented 40 to 90 ft | dawn | Deep basin (50 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 8 to 30 ft | dusk | Break off the point (20 ft) | Small spoon (gold), Jig + plastic larva |
| Winter | 15 to 50 ft chart-limited; documented 25 to 70 ft | midday & dawn | Deep basin (50 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
In spring, cisco (lake herring) run shallow here, mostly 10 to 40 ft. Summer pushes them deeper, 15 to 50 ft, and winter fish settle into 15 to 50 ft. Deep basin is the standout, a deep basin at roughly 50 ft, rated prime for summer cisco (lake herring). Time it for early morning. You won't need more than a vertical flutter spoon (small) or a drop-shot micro plastic most summer days.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Deep basin (50 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 15 to 50 ft chart-limited; documented 40 to 80 ft | dawn | Deep basin (50 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | Break off the point (20 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 15 to 50 ft chart-limited; documented 20 to 60 ft | dawn | Deep basin (50 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
The spring pattern is a shallow one: walleye in 4 to 15 ft. Midsummer fish sit out in 15 to 35 ft before dropping to 20 to 40 ft for winter. The spot to know is Break off the point, a drop-off in about 20 ft of water that rates prime for walleye in fall. Plan around the evening and early morning in the warm months. Summer baits: a crawler harness on bottom bouncer or a deep crankbait (trolled) gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Main-lake point (1 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Break off the point (20 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 12 to 40 ft | dusk & night | Break off the point (20 ft) | Jigging rap, Jig + big minnow |
| Winter | 20 to 40 ft | dusk & dawn | Break off the point (20 ft) | Jigging spoon + minnow head, Rattle bait |
In spring, yellow perch run shallow here, mostly 3 to 12 ft. Midsummer fish sit out in 10 to 30 ft before dropping to 15 to 35 ft for winter. Summer yellow perch concentrate at Break off the point, a prime-rated drop-off around 20 ft. Fish it in early morning and you'll meet the bite. You won't need more than a drop-shot micro plastics or a small spoon tipped with worm most summer days.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (2 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Break off the point (20 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Break off the point (20 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Break off the point (20 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Early season northern pike use the shallows, holding in 2 to 8 ft. Summer is an 8 to 20 ft game here, winter a 5 to 15 ft one. The chart's best answer is Shallow bay flat — weed flat, 2 ft, prime for spring. Best bite is early morning and the evening. Tie on a bucktail or a weedless spoon over cabbage and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (2 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (20 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Shallow feeding flat (16 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow feeding flat (16 ft) | Tip-ups, Large jigging spoon |
Spring burbot on Usnac Lake hold shallow, usually 15 to 50 ft. Depth-wise the year is flat: 15 to 50 ft in summer, 13 to 50 ft once it turns cold. The chart's best answer is Deep basin — deep basin, 50 ft, prime for spring. Prime time lands in after dark and midday. The summer box starts with a heavy jig + cut bait.
Depth note: when a documented seasonal range extends below this chart, the table shows the deepest mapped working water, not a verified holding depth.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 15 to 50 ft chart-limited; documented 25 to 70 ft | night & dusk | Deep basin (50 ft) | Glow jigging spoon + cut bait, Rattle bait (dark) |
| Summer | 15 to 50 ft chart-limited; documented 50 to 120 ft | night & midday | Deep basin (50 ft) | Heavy jig + cut bait |
| Fall | 15 to 50 ft chart-limited; documented 30 to 80 ft | night & dusk | Deep basin (50 ft) | Glow spoon + minnow head, Blade bait (slow) |
| Winter | 13 to 50 ft chart-limited; documented 15 to 60 ft | night & dusk | Deep basin (50 ft) | Glow tungsten + cut bait, Rattle spoon + minnow head |
The chart marks 7 structure features on Usnac Lake; the deepest is Deep basin at about 50 ft.
Season dates, license requirements, and size and bag limits for Ontario waters are set by the Ontario fishing regulations (FMZ summary) — and special regulations can apply to Usnac Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Usnac Lake is about 50 ft (15 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1970, a decades-old survey (a transect sounding survey).
Anglers target lake whitefish, cisco (lake herring), walleye, yellow perch, northern pike, burbot on Usnac Lake.
Deep basin is the top-rated area: a deep basin in about 50 ft of water that rates prime for lake whitefish in summer. Scroll up to the map for the complete spot list by species and season.
For lake whitefish, the summer bite is best in 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 Usnac Lake is regulated by the Ontario fishing regulations (FMZ summary). Check the official Ontario regulations for current license requirements, season dates, and size and bag limits — special regulations can apply to this specific water.
Radisson Lake 4 mi · Inlet Lake 5 mi · Opasatika Lake 5 mi · Opasatika L. 14 6 mi · Cromlech Lake 14 6 mi · Abbot Lake 5 6 mi · Opasatika Lake 15 6 mi · Penelton Lake 7 mi · Big Rice Lake 7 mi · Powell Lake 7 mi · Cooper Lake 7 mi · Opasatika Lake 16 8 mi
See how Usnac Lake stacks up: best walleye lakes in Ontario · best northern pike lakes in Ontario · best yellow perch lakes in Ontario · best lake whitefish lakes in Ontario
More water nearby: Algoma District fishing maps (1026 charts). Browse all Ontario fishing maps. See every water on DepthScout. Bathymetry: published agency survey data. 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.