Sign inSign up free Sign inSign up free Sign inSign up freeShared by DepthScout anglers. Exact spots stay private, always.
292-acre lake in Parry Sound District, Ontario. The lake tops out around 60 ft. The depth data here comes from the Ontario MNRF survey of 1970, a decades-old survey (a transect sounding survey). Every species below gets its seasonal read from the same numbers driving the chart.
Oastler Lake maps at 293 acres behind 6.7 miles of shoreline, broken up by 2 islands. A development index of 2.8 means a maze of bays and points: far more casting targets than a round bowl of the same size. About 47% of the surface sits shallower than 15 ft — that's the weed-and-bait zone. Call it 1.2 mi long by 0.9 mi wide at the broadest reach. It sits in Parry Sound District. Cochrane Lake sits 1 mi east — the closest neighbouring chart.
Spring splake on Oastler Lake hold shallow, usually 5 to 25 ft. By summer they slide out to 25 to 60 ft, and by winter most fish are in 10 to 45 ft. The chart's best answer is Break off the point — drop-off, 10 ft, prime for winter. Prime time lands in early morning and the evening. The summer box starts with a trolled spoon at the thermocline or a white tube jig (deep).
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 5 to 25 ft | dawn & dusk | Main-lake point (6 ft) | Small casting spoon (gold/orange), Inline spinner |
| Summer | 25 to 60 ft | dawn & dusk | Deep basin (60 ft) | Trolled spoon at the thermocline, White tube jig (deep) |
| Fall | 10 to 35 ft | dawn & dusk | Secondary point (16 ft) | Casting spoon, Jerkbait |
| Winter | 10 to 45 ft | dawn | Break off the point (10 ft) | Jigging spoon tipped with minnow head, Small white tube |
Spring puts cisco (lake herring) in skinny water — 10 to 40 ft is the zone. As the season builds they drop to 18 to 60 ft, wintering in 20 to 60 ft. Summer cisco (lake herring) concentrate at Deep basin, a prime-rated deep basin around 60 ft. Warm-month bites cluster around early morning. A vertical flutter spoon (small) or a drop-shot micro plastic covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Break off the point (10 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 18 to 60 ft | dawn | Deep basin (60 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | Break off the point (10 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 20 to 60 ft | dawn | Deep basin (60 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
Spring puts yellow perch 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 15 to 35 ft. Shallow bay flat is the standout, a weed flat at roughly 5 ft, rated prime for spring yellow perch. Plan around early morning in the warm months. A drop-shot micro plastics or a small spoon tipped with worm covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | midday & dawn | Shallow bay flat (5 ft) | Small jig + curly tail, Perch-pattern micro crank |
| Summer | 10 to 30 ft | dawn | Break off the point (10 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Break off the point (10 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Shallow feeding flat (20 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Spring northern pike on Oastler Lake hold shallow, usually 2 to 8 ft. They move out to 8 to 20 ft in summer and finish the year down in 5 to 15 ft. Put Shallow bay flat first on the milk run — a weed flat near 5 ft that grades prime for spring. The feeding windows run early morning and the evening. The summer box starts with a bucktail or a weedless spoon over cabbage.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 8 ft | midday & dawn | Shallow bay flat (5 ft) | #5 inline spinner, Spoon (red/white) |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (10 ft) | Bucktail, Weedless spoon over cabbage |
| Fall | 6 to 18 ft | midday & dawn | Break off the point (10 ft) | Big rubber (Bull Dawg style), Husky-style jerkbait |
| Winter | 5 to 15 ft | midday | Shallow bay flat (5 ft) | Tip-ups, Large jigging spoon |
Spring smallmouth bass on Oastler Lake hold shallow, usually 3 to 12 ft. They move out to 10 to 30 ft in summer and finish the year down in 20 to 45 ft. Put Secondary point first on the milk run — a point near 16 ft that grades prime for fall. The feeding windows run early morning and the evening. The summer box starts with a drop shot (goby/minnow) or a ned rig.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (6 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Break off the point (10 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Secondary point (16 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Break off the point (10 ft) | Blade bait, Hair jig |
Early season largemouth bass use the shallows, holding in 2 to 10 ft. Summer is an 8 to 20 ft game here, winter a 15 to 35 ft one. The chart's best answer is Shallow bay flat — weed flat, 5 ft, prime for spring. Best bite is early morning and the evening. Tie on a texas-rigged 10" worm or a deep-diving crankbait and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 2 to 10 ft | dawn & dusk | Shallow bay flat (5 ft) | Spinnerbait, Chatterbait |
| Summer | 8 to 20 ft | dawn & dusk | Break off the point (10 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (6 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 15 to 35 ft | midday | Break off the point (10 ft) | Blade bait, Jigging spoon |
Oastler Lake also holds rock bass (5 to 20 ft in summer), crappie (10 to 25 ft in summer), pumpkinseed (2 to 10 ft in summer), brown bullhead (3 to 12 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Oastler Lake carries 7 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 60 ft down.
Access data: Land Information Ontario — Fishing Access Point. Confirm conditions and fees locally before you launch.
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 Oastler Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Oastler Lake is about 60 ft (18 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1970, a decades-old survey (a transect sounding survey).
Anglers target splake, cisco (lake herring), yellow perch, northern pike, smallmouth bass, largemouth bass, rock bass, crappie, pumpkinseed, brown bullhead on Oastler Lake.
Deep basin is the top-rated area: a deep basin in about 60 ft of water that rates prime for cisco (lake herring) in summer. The interactive chart above rates every spot for each species and season.
For splake, the summer bite is best in early morning and the evening. Each species page section below lists the seasonal windows, and the map shows a live NOW badge when you're inside one.
Fishing on Oastler 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.
Cochrane Lake 1 mi · Vair Lake 2 mi · McNutt Lake 2 mi · Richmond Lake 2 mi · Wright Lake 2 mi · McGowan Lake 2 mi · Lovell Lake 2 mi · Haines Lake 3 mi · Otter Lake 3 mi · Tatai Lake 3 mi · Rankin Lake 3 mi · Blue Lake 3 mi
See how Oastler Lake stacks up: best largemouth bass lakes in Ontario · best smallmouth bass lakes in Ontario · best northern pike lakes in Ontario · best crappie lakes in Ontario
More water nearby: Parry Sound District fishing maps (441 charts). Browse all Ontario fishing maps or see every water on DepthScout. Bathymetry credit: state fisheries survey programs. 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.