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150,038-acre section. The French River delta, Key Harbour and Byng Inlet on north Georgian Bay: legendary muskie and walleye water in a maze of granite channels and weedy back bays. The lake tops out around 155 ft. The depth chart is built from real NOAA hydrographic survey soundings, so the humps, channels and drop-offs you see are measured, not guessed. Every species below gets its seasonal read from the same numbers driving the chart.
Traced from the shoreline, Georgian Bay - French River & Key Harbour runs 150,668 acres with 167.2 miles of edge, with 4 islands in the mix. An index of 3.1 puts the bank firmly in maze territory: point after pocket after cove, every one a casting target. The shallow band under 15 ft claims about 25% of the surface — that's where the groceries are. Call it 26.8 mi long by 17.5 mi wide at the broadest reach. For a second option, Bass Lake lies 8 mi north.
The spring pattern is a shallow one: muskellunge in 3 to 12 ft. Midsummer fish sit out in 8 to 25 ft before dropping to 15 to 35 ft for winter. The spot to know is Weed flat, a weed flat in about 5 ft of water that rates prime for muskellunge in spring. Plan around the evening and early morning in the warm months. Summer baits: a double-10 bucktail or a topwater (walk-the-dog / creeper) gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dusk | Weed flat (5 ft) | Smaller bucktail (#8 blades), 6" glide bait |
| Summer | 8 to 25 ft | dusk & dawn | Offshore hump (25 ft) | Double-10 bucktail, Topwater (walk-the-dog / creeper) |
| Fall | 8 to 30 ft | midday & dusk | Rock reef (9 ft) | Big rubber (Bull Dawg style), 10"+ glide bait |
| Winter | 15 to 35 ft | midday | Offshore hump (25 ft) | Large rubber, crawled slow |
Spring puts northern pike in skinny water — 2 to 8 ft is the zone. Warm water sends them out to 8 to 20 ft; cold water stacks them in 5 to 15 ft. Weed flat is the standout, a weed flat at roughly 5 ft, rated prime for spring northern pike. Plan around early morning and the evening in the warm months. A bucktail or a weedless spoon over cabbage covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Weed flat (5 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Weed flat (5 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Weed flat (5 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Weed flat (5 ft) | Tip-ups, Large jigging spoon |
Early season walleye use the shallows, holding in 4 to 15 ft. Expect a summer slide to 15 to 35 ft, then a winter hold in 20 to 40 ft. Put French River main outlet first on the milk run — an inflow / creek mouth near 14 ft that grades prime for spring. In summer the feeding windows fall in the evening and early morning. Tie on a crawler harness on bottom bouncer or a deep crankbait (trolled) and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | French River main outlet (14 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Offshore hump (25 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 12 to 40 ft | dusk & night | Sharp break (40 ft) | Jigging rap, Jig + big minnow |
| Winter | 20 to 40 ft | dusk & dawn | Offshore hump (25 ft) | Jigging spoon + minnow head, Rattle bait |
Spring puts smallmouth bass in skinny water — 3 to 12 ft is the zone. Warm water sends them out to 10 to 30 ft; cold water stacks them in 20 to 45 ft. Rock reef is the standout, a rock pile at roughly 3 ft, rated prime for spring smallmouth bass. Plan around early morning and the evening in the warm months. A drop shot (goby/minnow) or a ned rig covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Rock reef (3 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Offshore hump (25 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Rock reef (9 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Sharp break (40 ft) | Blade bait, Hair jig |
In spring, largemouth bass run shallow here, mostly 2 to 10 ft. Midsummer fish sit out in 8 to 20 ft before dropping to 15 to 35 ft for winter. Spring largemouth bass concentrate at Weed flat, a prime-rated weed flat around 5 ft. Fish it in early morning and the evening and you'll meet the bite. You won't need more than a texas-rigged 10" worm or a deep-diving crankbait most summer days.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Weed flat (5 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Weed flat (5 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Shoreline point (6 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 15 to 35 ft | midday | Sharp break (40 ft) | Blade bait, Jigging spoon |
Spring yellow perch on Georgian Bay - French River & Key Harbour hold shallow, usually 3 to 12 ft. They move out to 10 to 30 ft in summer and finish the year down in 15 to 35 ft. Put Weed flat first on the milk run — a weed flat near 5 ft that grades prime for spring. The feeding windows run early morning. The summer box starts with a drop-shot micro plastics or a small spoon tipped with worm.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Weed flat (5 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Offshore hump (25 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Offshore hump (25 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Offshore hump (25 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Georgian Bay - French River & Key Harbour also holds rock bass (5 to 20 ft in summer), crappie (10 to 25 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Count 27 structure marks on this chart. The deepest, Deepest basin, sits near 155 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 Georgian Bay - French River & Key Harbour specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Georgian Bay - French River & Key Harbour is about 155 ft (47 m) deep at its deepest point. The depth chart here comes from real NOAA hydrographic surveys, so the contours reflect measured depths.
Anglers target muskellunge, northern pike, walleye, smallmouth bass, largemouth bass, yellow perch, rock bass, crappie on Georgian Bay - French River & Key Harbour.
Weed flat is the top-rated area: a weed flat in about 5 ft of water that rates prime for northern pike in spring. The map above holds the full rated-spot list for every species and season.
For muskellunge, 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 Georgian Bay - French River & Key Harbour 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.
Bass Lake 8 mi · Eastern Outlet (French River) 11 mi · French River 11 mi · Western Channel (French River) 12 mi · Clear Lake 14 mi · Portage Lake 14 mi · Nisbet Lake 15 mi · Gut Lake 15 mi · Grundy Lake 15 mi · Bucke Lake 15 mi · Gurd Lake 15 mi · Pike Lake 16 mi
See how Georgian Bay - French River & Key Harbour stacks up: best largemouth bass lakes in Ontario · best smallmouth bass lakes in Ontario · best walleye lakes in Ontario · best northern pike lakes in Ontario
Browse all Ontario fishing maps or see every water on DepthScout. Bathymetry credit: NOAA hydrographic surveys. 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.