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Recent public catches load as you reach this section.
330-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. What the data behind the map says about each species, season by season:
The outline encloses 328 acres, worked by 3 miles of shoreline. At index 1.2 the outline is almost a bowl — read the depth changes, not the shoreline. Tip to tip the water measures near 0.9 mi with a 0.8-mi widest point. Thunder Bay District claims this one. If the bite dies, d'Orsonnens Lake is 6 mi to the southwest.
The spring pattern is a shallow one: walleye in 4 to 15 ft. As the season builds they drop to 6 to 20 ft, wintering in 6 to 20 ft. Top water on the chart: Deep basin, a deep basin in the 10 ft range, prime in winter. Time it for the evening and early morning. Summer baits: a crawler harness on bottom bouncer or a deep crankbait (trolled) gets it done.
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 | Break off the point (3 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 6 to 20 ft chart-limited; documented 15 to 35 ft | dusk & dawn | Deep basin (10 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 6 to 20 ft chart-limited; documented 12 to 40 ft | dusk & night | Deep basin (10 ft) | Jigging rap, Jig + big minnow |
| Winter | 6 to 20 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (10 ft) | Jigging spoon + minnow head, Rattle bait |
In spring, yellow perch run shallow here, mostly 3 to 12 ft. Summer pushes them deeper, 6 to 20 ft, and winter fish settle into 6 to 20 ft. Deep basin is the standout, a deep basin at roughly 10 ft, rated prime for fall yellow perch. Time it for early morning. You won't need more than a drop-shot micro plastics or a small spoon tipped with worm 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 | 3 to 12 ft | midday & dawn | Shallow bay flat (1 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 6 to 20 ft chart-limited; documented 10 to 30 ft | dawn | Deep basin (10 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 (10 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 6 to 20 ft chart-limited; documented 15 to 35 ft | midday & dawn | Deep basin (10 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Early season northern pike use the shallows, holding in 2 to 8 ft. Expect a summer slide to 8 to 20 ft, then a winter hold in 5 to 15 ft. Put Shallow bay flat first on the milk run — a weed flat near 1 ft that grades prime for spring. In summer the feeding windows fall in 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 (1 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (3 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (3 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (1 ft) | Tip-ups, Large jigging spoon |
6 pieces of structure are mapped here — Deep basin, around 10 ft, is the deepest of them.
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 Napper Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Napper Lake is about 20 ft (6 m) deep at its deepest point. 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.
Anglers target walleye, yellow perch, northern pike on Napper Lake.
Deep basin is the top-rated area: a deep basin in about 10 ft of water that rates prime for walleye in winter. The map above holds the full rated-spot list for every 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 Napper 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.
d'Orsonnens Lake 6 mi · Sim Lake 7 mi · Ogoki Reservoir 11 mi · Morden Lake 11 mi · Kagianagami Lake 12 mi · Faircloth Lake 13 mi · Lake I-291 15 mi · Elbow L. 16 mi · Kellow Lake 18 mi · Mahamo Lake 19 mi · Studd Lake 20 mi · Chipchase Lake 20 mi
See how Napper Lake stacks up: 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.