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278-acre lake in Parry Sound District, Ontario. The lake tops out around 46 ft. These contours are modeled — built from the real shoreline and the water's maximum depth — so read them as a guide, never as navigation. Below is the species-by-species picture, pulled from the same data the map uses.
Drawn out, this is 277 acres of water rimmed by 8.2 miles of bank, with a single island in the mix. With a shoreline index of 3.5, this water is all arms and coves — edge habitat well beyond its acreage. 37% of the surface is littoral (under ~15 ft), per the model — cover, weeds and forage water. Tip to tip the water measures near 1.8 mi with a 1.1-mi widest point. You'll find it in Parry Sound District. The nearest mapped water is Black Oak Lake, 2 mi to the east.
Early season cisco (lake herring) use the shallows, holding in 10 to 40 ft. Summer is a 14 to 46 ft game here, winter a 14 to 46 ft one. The chart's best answer is Deep basin — deep basin, 39 ft, prime for spring. Best bite is early morning. Tie on a vertical flutter spoon (small) or a drop-shot micro plastic and you're in the game.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Deep basin (39 ft) | Small silver spoon, Tiny swim jig (white) |
| Summer | 14 to 46 ft | dawn | Deep basin (39 ft) | Vertical flutter spoon (small), Drop-shot micro plastic |
| Fall | 5 to 25 ft | dusk & dawn | Break off the point (21 ft) | Small casting spoon, Inline spinner (silver) |
| Winter | 14 to 46 ft | dawn | Deep basin (39 ft) | Small jigging spoon (glow/silver), Tungsten jig + minnow head |
Come spring, look for walleye tight to the bank in 4 to 15 ft. Expect a summer slide to 15 to 35 ft, then a winter hold in 20 to 40 ft. Start at Break off the point. It's a drop-off holding about 21 ft of water and rates prime come fall. Prime time lands in the evening and early morning. A crawler harness on bottom bouncer or a deep crankbait (trolled) is the honest summer answer here.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | dusk & dawn | Main-lake point (12 ft) | 1/8 oz jig + minnow, Hair jig |
| Summer | 15 to 35 ft | dusk & dawn | Break off the point (21 ft) | Crawler harness on bottom bouncer, Deep crankbait (trolled) |
| Fall | 12 to 40 ft | dusk & night | Break off the point (21 ft) | Jigging rap, Jig + big minnow |
| Winter | 20 to 40 ft | dusk & dawn | Deep basin (39 ft) | Jigging spoon + minnow head, Rattle bait |
Come spring, look for yellow perch tight to the bank in 3 to 12 ft. They move out to 10 to 30 ft in summer and finish the year down in 15 to 35 ft. If you only fish one area, make it Shallow bay flat: a weed flat around 6 ft that scores prime in spring. Best bite is 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 (21 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Break off the point (21 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Deep basin (39 ft) | Tungsten jig + spikes, Rattle spoon (small) |
Start shallow in spring: northern pike sit in 2 to 8 ft that time of year. Warm water sends them out to 8 to 20 ft; cold water stacks them in 5 to 15 ft. Top water on the chart: Shallow bay flat, a weed flat in the 6 ft range, prime in spring. Fish it in early morning and the evening and you'll meet the bite. 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 |
Start shallow in spring: smallmouth bass sit in 3 to 12 ft that time of year. Warm water sends them out to 10 to 30 ft; cold water stacks them in 20 to 45 ft. Top water on the chart: Main-lake point, a point in the 12 ft range, prime in fall. Fish it in early morning and the evening and you'll meet the bite. Throw a drop shot (goby/minnow) or a ned rig until the fish tell you otherwise.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 12 ft | dawn & dusk | Main-lake point (12 ft) | Ned rig, Tube jig |
| Summer | 10 to 30 ft | dawn & dusk | Break off the point (21 ft) | Drop shot (goby/minnow), Ned rig |
| Fall | 8 to 25 ft | midday & dawn | Main-lake point (12 ft) | Jerkbait, Blade bait |
| Winter | 20 to 45 ft | midday | Break off the point (21 ft) | Blade bait, Hair jig |
The spring pattern is a shallow one: largemouth bass in 2 to 10 ft. Midsummer fish sit out in 8 to 20 ft before dropping to 15 to 35 ft for winter. The spot to know is Shallow bay flat, a weed flat in about 6 ft of water that rates prime for largemouth bass in spring. Plan around early morning and the evening in the warm months. 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 | Break off the point (21 ft) | Texas-rigged 10" worm, Deep-diving crankbait |
| Fall | 4 to 15 ft | midday & dawn | Main-lake point (12 ft) | Squarebill crankbait (shad), Spinnerbait |
| Winter | 15 to 35 ft | midday | Break off the point (21 ft) | Blade bait, Jigging spoon |
Rock Island Lake also holds rock bass (5 to 20 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.
Count 6 structure marks on this chart. The deepest, Deep basin, sits near 39 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 Rock Island Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Rock Island Lake is about 46 ft (14 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, smallmouth bass, largemouth bass, rock bass, pumpkinseed, brown bullhead on Rock Island Lake.
Deep basin is the top-rated area: a deep basin in about 39 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 Rock Island 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.
Black Oak Lake 2 mi · Wiwassasegen Lake 3 mi · Raven Lake 3 mi · Birch Lake 4 mi · Carling L. K4 4 mi · Wilson Lake 5 mi · Trout Lake 5 mi · Skerryvore Lake 5 mi · Little Wilson Lake 6 mi · Partridge Lake 6 mi · Wallace Lake 6 mi · Horseshoe Lake 6 mi
See how Rock Island Lake 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
More water nearby: Parry Sound District fishing maps (441 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.