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233-acre lake in Thunder Bay District, Ontario. The lake tops out around 37 ft. What you see is a modeled chart: the shoreline is real, the max depth is published, and the contours between are estimated. Plan with it; don't navigate by it. The rest of this page walks each species through its year, using the map's own scoring.
Traced from the shoreline, Upper Port L. runs 233 acres with 5.5 miles of edge. The 2.6 development index tells the story — a convoluted bank whose fishable edge far outruns the acreage. The shallow band under 15 ft claims about 71% of the surface on the model — that's where the groceries are. Figure 1.6 mi of water from one end to the other, 0.7 mi at the beam. You'll find it in Thunder Bay District. The nearest mapped water is Patterson L., 4 mi to the northeast.
Spring cisco (lake herring) on Upper Port L. hold shallow, usually 9 to 37 ft. Depth-wise the year is flat: 11 to 37 ft in summer, 11 to 37 ft once it turns cold. Put Deep basin first on the milk run — a deep basin near 31 ft that grades prime for spring. The feeding windows run 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 | 9 to 37 ft chart-limited; documented 10 to 40 ft | dawn & dusk | Deep basin (31 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 11 to 37 ft chart-limited; documented 40 to 80 ft | dawn | Deep basin (31 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | Break off the point (17 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 11 to 37 ft chart-limited; documented 20 to 60 ft | dawn | Deep basin (31 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
When the water first warms, walleye slide up into 4 to 15 ft. By summer they slide out to 15 to 35 ft, and by winter most fish are in 11 to 37 ft. If you only fish one area, make it Break off the point: a drop-off around 17 ft that scores prime in fall. In summer the feeding windows fall in 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 | Main-lake point (9 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Break off the point (17 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 11 to 37 ft chart-limited; documented 12 to 40 ft | dusk & night | Break off the point (17 ft) | Jigging rap, Jig + big minnow |
| Winter | 11 to 37 ft chart-limited; documented 20 to 40 ft | dusk & dawn | Deep basin (31 ft) | Jigging spoon + minnow head, Rattle bait |
When the water first warms, yellow perch slide up into 3 to 12 ft. Summer is a 10 to 30 ft game here, winter a 15 to 35 ft one. Start at Shallow bay flat. It's a weed flat holding about 4 ft of water and rates prime come spring. The feeding windows run early morning. Keep a drop-shot micro plastics or a small spoon tipped with worm rigged through the warm months.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (4 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Break off the point (17 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Deep basin (31 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Deep basin (31 ft) | Tungsten jig + spikes, Rattle spoon (small) |
The spring pattern is a shallow one: northern pike in 2 to 8 ft. Midsummer fish sit out in 8 to 20 ft before dropping to 5 to 15 ft for winter. The spot to know is Shallow bay flat, a weed flat in about 4 ft of water that rates prime for northern pike in spring. Plan around early morning and the evening in the warm months. 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 (4 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (17 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (17 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (4 ft) | Tip-ups, Large jigging spoon |
The chart marks 6 structure features on Upper Port L.; the deepest is Deep basin at about 31 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 Upper Port L. specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Upper Port L. is about 37 ft (11 m) deep at its deepest point. The contours here are modeled from the water's real shape and maximum depth, so treat them as a rough guide.
Anglers target cisco (lake herring), walleye, yellow perch, northern pike on Upper Port L..
Deep basin is the top-rated area: a deep basin in about 31 ft of water that rates prime for cisco (lake herring) in spring. The map above holds the full rated-spot list for every species and season.
For cisco (lake herring), 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 Upper Port L. 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.
Patterson L. 4 mi · Houghton Lake 4 mi · Fowler Lake 5 mi · Barnard Lake 7 mi · Fly Lake 7 mi · Die Lake 8 mi · Fairchild Lake 8 mi · Zen Lake 8 mi · Farrington Lake 9 mi · Bent Lake 9 mi · Shoehorn L. 9 mi · Lewis Lake 10 mi
See how Upper Port L. stacks up: best walleye lakes in Ontario · best northern pike lakes in Ontario · best yellow perch lakes in Ontario · best cisco (lake herring) lakes in Ontario
More water nearby: Thunder Bay District fishing maps (662 charts). Browse all Ontario fishing maps. See every water on DepthScout. 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.