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Recent public catches load as you reach this section.
97-acre lake in Thunder Bay District, Ontario. The lake tops out around 20 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 a transect sounding survey by the Ontario MNRF. The rest of this page walks each species through its year, using the map's own scoring.
The outline encloses 98 acres, worked by 2.3 miles of shoreline. A middling shoreline index (1.7) gives it some bays to work without being a maze. The shallow band under 15 ft claims about 53% of the surface — that's where the groceries are. Call it 0.7 mi long by 0.4 mi wide at the broadest reach. It sits in Thunder Bay District. Pete Lake sits 3 mi southwest — the closest neighbouring chart.
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, brook trout slide up into 2 to 15 ft. By summer they slide out to 6 to 20 ft, and by winter most fish are in 3 to 20 ft. If you only fish one area, make it Deep basin: a deep basin around 20 ft that scores prime in summer. In summer the feeding windows fall in early morning and the evening. Keep a small spoon fished deep or a trolled lake-clear wobbler + 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 | 2 to 15 ft | dawn & dusk | Main-lake point (3 ft) | Small inline spinner (gold), Tiny spoon |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn & dusk | Deep basin (20 ft) | Small spoon fished deep, Trolled lake-clear wobbler + worm |
| Fall | 2 to 15 ft | midday & dawn | Main-lake point (3 ft) | Small spoon (orange), Spinner |
| Winter | 3 to 20 ft | dawn | Deep basin (20 ft) | Small jigging spoon, Tungsten jig + plastic |
Start shallow in spring: walleye sit in 4 to 15 ft that time of year. Warm water sends them out to 6 to 20 ft; cold water stacks them in 6 to 20 ft. Top water on the chart: Break off the point, a drop-off in the 13 ft range, prime in fall. Fish it in the evening and early morning and you'll meet the bite. Throw a crawler harness on bottom bouncer or a deep crankbait (trolled) until the fish tell you otherwise.
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 (7 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 6 to 20 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Break off the point (13 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 6 to 20 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (13 ft) | Jigging rap, Jig + big minnow |
| Winter | 6 to 20 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (20 ft) | Jigging spoon + minnow head, Rattle bait |
Spring puts yellow perch in skinny water — 3 to 12 ft is the zone. Warm water sends them out to 6 to 20 ft; cold water stacks them in 6 to 20 ft. Shallow bay flat is the standout, a weed flat at roughly 6 ft, rated prime for spring yellow perch. Plan around early morning in the warm months. A drop-shot micro plastics or a small spoon tipped with worm covers the summer program.
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 (6 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (20 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 6 to 20 ft chart-limited; documented 12 to 35 ft | midday | Deep basin (20 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (20 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Spring northern pike on Marks Lake hold shallow, usually 2 to 8 ft. They move out to 8 to 20 ft in summer and finish the year down in 5 to 15 ft. Put Shallow bay flat first on the milk run — a weed flat near 6 ft that grades prime for spring. The feeding windows run early morning and the evening. The summer box starts with a bucktail or a weedless spoon over cabbage.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (6 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (13 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Shallow bay flat (6 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (6 ft) | Tip-ups, Large jigging spoon |
Spring smallmouth bass on Marks Lake hold shallow, usually 3 to 12 ft. They move out to 6 to 20 ft in summer and finish the year down in 6 to 20 ft. Put Secondary point first on the milk run — a point near 7 ft that grades prime for fall. The feeding windows run early morning and the evening. The summer box starts with a drop shot (goby/minnow) or a ned rig.
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 | dawn & dusk | Main-lake point (3 ft) | Ned rig, Tube jig |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn & dusk | Break off the point (13 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 6 to 20 ft chart-limited; documented 8 to 25 ft | midday & dawn | Secondary point (7 ft) | Jerkbait, Blade bait |
| Winter | 6 to 20 ft chart-limited; documented 20 to 45 ft | midday | Break off the point (13 ft) | Blade bait, Hair jig |
Spring puts cisco (lake herring) in skinny water — 5 to 20 ft is the zone. Summer fish stay in 6 to 20 ft, and winter fish hold in 6 to 20 ft. Spring cisco (lake herring) concentrate at Deep basin, a prime-rated deep basin around 20 ft. Warm-month bites cluster around early morning. A vertical flutter spoon (small) or a drop-shot micro plastic covers the summer program.
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 | 5 to 20 ft chart-limited; documented 10 to 40 ft | dawn & dusk | Deep basin (20 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 6 to 20 ft chart-limited; documented 40 to 80 ft | dawn | Deep basin (20 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 4 to 20 ft chart-limited; documented 5 to 25 ft | dusk & dawn | Break off the point (13 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 6 to 20 ft chart-limited; documented 20 to 60 ft | dawn | Deep basin (20 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
Marks Lake also holds lake whitefish (6 to 20 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Structure-wise the chart holds 6 features, led in depth by Deep basin at roughly 20 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 Marks Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Marks Lake is about 20 ft (6 m) deep at its deepest point. The depth data here comes from a transect sounding survey by the Ontario MNRF.
Anglers target brook trout, walleye, yellow perch, northern pike, smallmouth bass, cisco (lake herring), lake whitefish on Marks Lake.
Break off the point is the top-rated area: a drop-off in about 13 ft of water that rates prime for walleye in fall. The map above holds the full rated-spot list for every species and season.
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.
Fishing on Marks 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.
Pete Lake 3 mi · Adrian Lake 4 mi · Stephens Lake 5 mi · West Pennock 5 mi · Echo Lake 6 mi · Thunder Lake 7 mi · Blossom Lake 13 mi · Sunset Lake 15 mi · Chub Lake 15 mi · Whitefish Lake 15 mi · Oliver Lake 15 mi · Batwing Lake 16 mi
See how Marks Lake stacks up: best smallmouth bass lakes in Ontario · best walleye lakes in Ontario · best northern pike lakes in Ontario · best yellow perch 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.