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Recent public catches load as you reach this section.
1,514-acre lake in Thunder Bay District, Ontario. The lake tops out around 25 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 1973, a decades-old survey (a transect sounding survey). Here's the year, species by species, as the scoring engine sees it.
Drawn out, this is 1,521 acres of water rimmed by 25.6 miles of bank, broken up by 12 islands. An index of 4.7 puts the bank firmly in maze territory: point after pocket after cove, every one a casting target. Littoral water — the productive band under ~15 ft — makes up 98% of this chart. End to end it runs roughly 6.3 mi, about 1.5 mi across. The water lies in Thunder Bay District. Closest neighbour on DepthScout: Lally Lake, 3 mi east of here.
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.
When the water first warms, walleye slide up into 4 to 15 ft. Summer is an 8 to 25 ft game here, winter an 8 to 25 ft one. Start at Deep basin. It's a deep basin holding about 22 ft of water and rates prime come winter. The feeding windows run the evening and early morning. Keep a crawler harness on bottom bouncer or a deep crankbait (trolled) rigged through the warm months.
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 | 4 to 15 ft | dusk & dawn | Secondary point (3 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 8 to 25 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Deep basin (22 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 8 to 25 ft chart-limited; documented 12 to 40 ft | dusk & night | Deep basin (22 ft) | Jigging rap, Jig + big minnow |
| Winter | 8 to 25 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (22 ft) | Jigging spoon + minnow head, Rattle bait |
When the water first warms, yellow perch slide up into 3 to 12 ft. By summer they slide out to 8 to 25 ft, and by winter most fish are in 8 to 25 ft. If you only fish one area, make it Deep basin: a deep basin around 22 ft that scores prime in fall. In summer the feeding windows fall in early morning. Keep a drop-shot micro plastics or a small spoon tipped with worm rigged through the warm months.
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 | 3 to 12 ft | midday & dawn | Shallow bay flat (2 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 8 to 25 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (22 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 8 to 25 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (22 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 8 to 25 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (22 ft) | Tungsten jig + spikes, Rattle spoon (small) |
The spring pattern is a shallow one: northern pike in 2 to 8 ft. As the season builds they drop to 8 to 20 ft, wintering in 5 to 15 ft. Top water on the chart: Shallow bay flat, a weed flat in the 2 ft range, prime in spring. Time it for early morning and the evening. Summer baits: a bucktail or a weedless spoon over cabbage gets it done.
| 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 | Shallow feeding flat (20 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Shallow feeding flat (20 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (2 ft) | Tip-ups, Large jigging spoon |
Spring cisco (lake herring) on Gamsby Lake hold shallow, usually 6 to 25 ft. Depth-wise the year is flat: 8 to 25 ft in summer, 8 to 25 ft once it turns cold. The chart's best answer is Deep basin — deep basin, 22 ft, prime for spring. Prime time lands in early morning. The summer box starts with a vertical flutter spoon (small) or a drop-shot micro plastic.
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 | 6 to 25 ft chart-limited; documented 10 to 40 ft | dawn & dusk | Deep basin (22 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 8 to 25 ft chart-limited; documented 40 to 80 ft | dawn | Deep basin (22 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | Break off the point (2 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 8 to 25 ft chart-limited; documented 20 to 60 ft | dawn | Deep basin (22 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
Spring lake whitefish on Gamsby Lake hold shallow, usually 8 to 25 ft. Depth-wise the year is flat: 8 to 25 ft in summer, 8 to 25 ft once it turns cold. The chart's best answer is Deep basin — deep basin, 22 ft, prime for summer. Prime time lands in early morning. The summer box starts with a blade bait vertical or a small jigging spoon.
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 | 8 to 25 ft chart-limited; documented 15 to 45 ft | midday & dawn | Shallow feeding flat (20 ft) | Small jig + waxworm, Blade bait (small) |
| Summer | 8 to 25 ft chart-limited; documented 40 to 90 ft | dawn | Deep basin (22 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 7 to 25 ft chart-limited; documented 8 to 30 ft | dusk | Break off the point (2 ft) | Small spoon (gold), Jig + plastic larva |
| Winter | 8 to 25 ft chart-limited; documented 25 to 70 ft | midday & dawn | Deep basin (22 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
The chart marks 7 structure features on Gamsby Lake; the deepest is Deep basin at about 22 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 Gamsby Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Gamsby Lake is about 25 ft (8 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1973, a decades-old survey (a transect sounding survey).
Anglers target walleye, yellow perch, northern pike, cisco (lake herring), lake whitefish on Gamsby Lake.
Deep basin is the top-rated area: a deep basin in about 22 ft of water that rates prime for walleye in winter. 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 Gamsby 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.
Lally Lake 3 mi · Hartley L. 4 mi · Rogers Lake 5 mi · Wintering Lake 7 mi · Finlayson Lake 7 mi · Baton Lake 9 mi · Wig Lake 10 mi · Goldfield Lake 10 mi · Tomahawk Lake 12 mi · Wildgoose Lake 14 mi · Turkey Lake 14 mi · Gathering Lake 14 mi
See how Gamsby 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: Thunder Bay District fishing maps (662 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.