Sign inSign up free Sign inSign up free Sign inSign up freeLake depth chart
Today's read
Shared by DepthScout anglers. Exact spots stay private, always.
47-acre lake in York Regional Municipality, Ontario. The lake tops out around 50 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 season-by-season read for each species follows, from the map's own numbers.
Traced from the shoreline, Mary Lake runs 47 acres with 1.5 miles of edge. The shoreline is moderately structured (index 1.5) — enough points and pockets to pattern. Roughly 33% of the water is 15 ft or less as modeled, the band where the food chain lives. Tip to tip the water measures near 0.5 mi with a 0.3-mi widest point. The water lies in York Regional Municipality. For a second option, Lake Seneca lies 1 mi east.
Come spring, look for yellow perch tight to the bank in 3 to 12 ft. Expect a summer slide to 10 to 30 ft, then a winter hold in 15 to 35 ft. Start at Shallow bay flat. It's a weed flat holding about 6 ft of water and rates prime come spring. Prime time lands in early morning. A drop-shot micro plastics or a small spoon tipped with worm is the honest summer answer here.
| 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 | 10 to 30 ft | dawn | Break off the point (23 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Break off the point (23 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Break off the point (23 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Start shallow in spring: northern pike sit in 2 to 8 ft that time of year. Summer pushes them deeper, 8 to 20 ft, and winter fish settle into 5 to 15 ft. The spot to know is Shallow bay flat, a weed flat in about 6 ft of water that rates prime for northern pike in spring. Warm-month bites cluster around early morning and the evening. Throw a bucktail or a weedless spoon over cabbage until the fish tell you otherwise.
| 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 | Shallow bay flat (6 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 |
The spring pattern is a shallow one: largemouth bass in 2 to 10 ft. As the season builds they drop to 8 to 20 ft, wintering in 15 to 35 ft. Top water on the chart: Shallow bay flat, a weed flat in the 6 ft range, prime in spring. Time it for early morning and the evening. Summer baits: a texas-rigged 10" worm or a deep-diving crankbait gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (6 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Main-lake point (13 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (13 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 15 to 35 ft | midday | Break off the point (23 ft) | Blade bait, Jigging spoon |
Early season rock bass use the shallows, holding in 2 to 10 ft. Expect a summer slide to 5 to 20 ft, then a winter hold in 12 to 30 ft. Put Main-lake point first on the milk run — a point near 13 ft that grades prime for summer. In summer the feeding windows fall in the evening. Tie on a ned rig (small) or a marabou jig and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | midday & dawn | open water | 1/16 oz jig + grub, Small inline spinner |
| Summer | 5 to 20 ft | dusk | Main-lake point (13 ft) | Ned rig (small), Marabou jig |
| Fall | 8 to 22 ft | midday | Break off the point (23 ft) | Small tube jig, Inline spinner |
| Winter | 12 to 30 ft | midday | Break off the point (23 ft) | Tungsten jig + plastic, Small spoon + spike |
Early season pumpkinseed use the shallows, holding in 1 to 8 ft. Expect a summer slide to 2 to 10 ft, then a winter hold in 6 to 18 ft. Put Shallow bay flat first on the milk run — a weed flat near 6 ft that grades prime for spring. In summer the feeding windows fall in the evening and early morning. Tie on a micro tube or a sponge spider (fly) and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 1 to 8 ft | midday & dusk | Shallow bay flat (6 ft) | Micro jig under a float, Tiny beetle-spin |
| Summer | 2 to 10 ft | dusk & dawn | Shallow bay flat (6 ft) | Micro tube, Sponge spider (fly) |
| Fall | 4 to 14 ft | dusk & dawn | Shallow bay flat (6 ft) | Micro jig + waxworm, Small spoon tipped |
| Winter | 6 to 18 ft | dawn | Shallow bay flat (6 ft) | Tungsten ice jig + plastic, Tiny spoon |
In spring, brown bullhead run shallow here, mostly 2 to 8 ft. Summer pushes them deeper, 3 to 12 ft, and winter fish settle into 10 to 25 ft. Shallow bay flat is the standout, a weed flat at roughly 6 ft, rated prime for spring brown bullhead. Time it for after dark and the evening.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | dusk & night | Shallow bay flat (6 ft) | |
| Summer | 3 to 12 ft | night & dusk | Shallow bay flat (6 ft) | |
| Fall | 5 to 15 ft | dusk | Shallow bay flat (6 ft) | |
| Winter | 10 to 25 ft | midday | Deep basin (43 ft) |
Mary Lake carries 5 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 43 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 Mary Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Mary Lake is about 50 ft (15 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 yellow perch, northern pike, largemouth bass, rock bass, pumpkinseed, brown bullhead on Mary Lake.
Shallow bay flat is the top-rated area: a weed flat in about 6 ft of water that rates prime for yellow perch in spring. Every other rated spot, per species and season, is on the map above.
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 Mary 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.
Lake Seneca 1 mi · Hackett Lake 2 mi · Thompson Lake 4 mi · Philips Lake 5 mi · Bond Lake 5 mi · Wilcox Lake 6 mi · St. George Lake 6 mi · Haynes Lake 7 mi · Simeon Lake 8 mi · Preston Lake 9 mi · Musselman Lake 15 mi · Shadow Lake 15 mi
See how Mary Lake stacks up: best largemouth bass lakes in Ontario · best northern pike lakes in Ontario · best yellow perch lakes in Ontario · best rock bass lakes in Ontario
More water nearby: York Regional Municipality fishing maps (16 charts). Browse all Ontario fishing maps or 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.