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141-acre lake in Nipissing District, Ontario. The lake tops out around 76 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 1979, a decades-old survey (an MNRF lake survey). The season-by-season read for each species follows, from the map's own numbers.
Joan L. 4 maps at 141 acres behind 4.5 miles of shoreline. An index of 2.7 puts the bank firmly in maze territory: point after pocket after cove, every one a casting target. About 81% of the surface sits shallower than 15 ft — that's the weed-and-bait zone. Call it 1 mi long by 0.8 mi wide at the broadest reach. Nipissing District claims this one. If the bite dies, Redbark Lake is 2 mi to the south.
Start shallow in spring: yellow perch sit in 3 to 12 ft that time of year. Summer pushes them deeper, 10 to 30 ft, and winter fish settle into 15 to 35 ft. The spot to know is Shallow bay flat, a weed flat in about 1 ft of water that rates prime for yellow perch in spring. Warm-month bites cluster around early morning. Throw a drop-shot micro plastics or a small spoon tipped with worm until the fish tell you otherwise.
| 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 | 10 to 30 ft | dawn | Break off the point (1 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Deep basin (68 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Deep basin (68 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Come spring, look for smallmouth bass tight to the bank in 3 to 12 ft. Expect a summer slide to 10 to 30 ft, then a winter hold in 20 to 45 ft. Start at Main-lake point. It's a point holding about 1 ft of water and rates good come spring. Prime time lands in early morning and the evening. A drop shot (goby/minnow) or a ned rig is the honest summer answer here.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (1 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Break off the point (1 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Main-lake point (1 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Break off the point (1 ft) | Blade bait, Hair jig |
Joan L. 4 carries 6 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 68 ft down.
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 Joan L. 4 specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Joan L. 4 is about 76 ft (23 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1979, a decades-old survey (an MNRF lake survey).
Anglers target yellow perch, smallmouth bass on Joan L. 4.
Shallow bay flat is the top-rated area: a weed flat in about 1 ft of water that rates prime for yellow perch in spring. Open the map above to see every rated spot for each species and season.
For yellow perch, 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 Joan L. 4 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.
Redbark Lake 2 mi · Secret Lake 2 mi · Allan Lake 3 mi · Herbert Lake 3 mi · Lower Bass Lake 4 mi · Upper Bass Lake 4 mi · Price Lake 4 mi · Hillcrest Lake 5 mi · Side Rock Lake 6 mi · Cummings Lake 6 mi · Malloch Lake 6 mi · Obabika Lake 6 mi
See how Joan L. 4 stacks up: best smallmouth bass lakes in Ontario · best yellow perch lakes in Ontario
More water nearby: Nipissing District fishing maps (683 charts). Browse all Ontario fishing maps or 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.