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1,268-acre lake in Haliburton County, Ontario. The lake tops out around 100 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 1968, a decades-old survey (an MNRF lake survey). The season-by-season read for each species follows, from the map's own numbers.
On the chart, Rock Lake draws 1,269 acres inside 18.7 miles of shoreline, with 3 islands in the mix. The 3.7 development index tells the story — a convoluted bank whose fishable edge far outruns the acreage. The shallow band under 15 ft claims about 66% of the surface — that's where the groceries are. End to end it runs roughly 3.1 mi, about 2.1 mi across. You'll find it in Haliburton County. Closest neighbour on DepthScout: Rosepond Lake, 1 mi north of here.
The spring pattern is a shallow one: lake trout in 10 to 40 ft. Midsummer fish sit out in 30 to 100 ft before dropping to 20 to 80 ft for winter. The spot to know is Deep basin, a deep basin in about 91 ft of water that rates prime for lake trout in summer. Plan around early morning in the warm months. Summer baits: a white tube jig (deep) or a magnum spoon on downrigger gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 10 to 40 ft | dawn & dusk | Main-lake point (1 ft) | Casting spoon over shoals, Jerkbait (shallow) |
| Summer | 30 to 100 ft | dawn | Deep basin (91 ft) | White tube jig (deep), Magnum spoon on downrigger |
| Fall | 10 to 50 ft | dusk & dawn | Main-lake point (1 ft) | Heavy casting spoon, Jigging rap over reefs |
| Winter | 20 to 80 ft | dawn | Deep basin (91 ft) | White tube jig, Airplane jig |
Start shallow in spring: splake sit in 5 to 25 ft that time of year. Warm water sends them out to 25 to 60 ft; cold water stacks them in 10 to 45 ft. Top water on the chart: Break off the point, a drop-off in the 1 ft range, prime in winter. Fish it in early morning and the evening and you'll meet the bite. Throw a trolled spoon at the thermocline or a white tube jig (deep) until the fish tell you otherwise.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 5 to 25 ft | dawn & dusk | Main-lake point (1 ft) | Small casting spoon (gold/orange), Inline spinner |
| Summer | 25 to 60 ft | dawn & dusk | Break off the point (1 ft) | Trolled spoon at the thermocline, White tube jig (deep) |
| Fall | 10 to 35 ft | dawn & dusk | Main-lake point (1 ft) | Casting spoon, Jerkbait |
| Winter | 10 to 45 ft | dawn | Break off the point (1 ft) | Jigging spoon tipped with minnow head, Small white tube |
Come spring, look for lake whitefish tight to the bank in 15 to 45 ft. They move out to 40 to 90 ft in summer and finish the year down in 25 to 70 ft. If you only fish one area, make it Deep basin: a deep basin around 91 ft that scores prime in summer. Best bite is early morning. A blade bait vertical or a small jigging spoon is the honest summer answer here.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 15 to 45 ft | midday & dawn | Shallow feeding flat (23 ft) | Small jig + waxworm, Blade bait (small) |
| Summer | 40 to 90 ft | dawn | Deep basin (91 ft) | Blade bait vertical, Small jigging spoon |
| Fall | 8 to 30 ft | dusk | Break off the point (1 ft) | Small spoon (gold), Jig + plastic larva |
| Winter | 25 to 70 ft | midday & dawn | Shallow feeding flat (23 ft) | Jigging spoon + bead chain, Tungsten jig + waxie |
Early season yellow perch use the shallows, holding in 3 to 12 ft. Summer is a 10 to 30 ft game here, winter a 15 to 35 ft one. The chart's best answer is Shallow bay flat — weed flat, 1 ft, prime for spring. Best bite is early morning. Tie on a drop-shot micro plastics or a small spoon tipped with worm and you're in the game.
| 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 | Shallow feeding flat (23 ft) | Drop-shot micro plastics, Small spoon tipped with worm |
| Fall | 12 to 35 ft | midday | Deep basin (91 ft) | Jigging spoon (small), Perch rig / spreader |
| Winter | 15 to 35 ft | midday & dawn | Shallow feeding flat (23 ft) | Tungsten jig + spikes, Rattle spoon (small) |
In spring, smallmouth bass run shallow here, mostly 3 to 12 ft. Midsummer fish sit out in 10 to 30 ft before dropping to 20 to 45 ft for winter. Spring smallmouth bass concentrate at Main-lake point, a good-rated point around 1 ft. Fish it in early morning and the evening and you'll meet the bite. You won't need more than a drop shot (goby/minnow) or a ned rig most summer days.
| 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 |
Come spring, look for pumpkinseed tight to the bank in 1 to 8 ft. They move out to 2 to 10 ft in summer and finish the year down in 6 to 18 ft. If you only fish one area, make it Shallow bay flat: a weed flat around 1 ft that scores prime in spring. Best bite is the evening and early morning. A micro tube or a sponge spider (fly) is the honest summer answer here.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 1 to 8 ft | midday & dusk | Shallow bay flat (1 ft) | Micro jig under a float, Tiny beetle-spin |
| Summer | 2 to 10 ft | dusk & dawn | Shallow bay flat (1 ft) | Micro tube, Sponge spider (fly) |
| Fall | 4 to 14 ft | dusk & dawn | Shallow bay flat (1 ft) | Micro jig + waxworm, Small spoon tipped |
| Winter | 6 to 18 ft | dawn | Shallow bay flat (1 ft) | Tungsten ice jig + plastic, Tiny spoon |
Rock Lake also holds brown bullhead (3 to 12 ft in summer), burbot (30 to 100 ft in summer). Pick any of them on the map above for rated spots and bait picks.
Structure-wise the chart holds 7 features, led in depth by Deep basin at roughly 91 ft.
Access data: Geospatial Ontario - Fishing Access Points. 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 Rock Lake specifically, so confirm the current rules before you fish.
Check the official Ontario fishing regulations →
Rock Lake is about 100 ft (30 m) deep at its deepest point. The depth data here comes from the Ontario MNRF survey of 1968, a decades-old survey (an MNRF lake survey).
Anglers target lake trout, splake, lake whitefish, yellow perch, smallmouth bass, pumpkinseed, brown bullhead, burbot on Rock Lake.
Deep basin is the top-rated area: a deep basin in about 91 ft of water that rates prime for lake trout in summer. Every other rated spot, per species and season, is on the map above.
For lake trout, 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 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.
Rosepond Lake 1 mi · Aubrey Lake 2 mi · Gordon Lake 2 mi · Sylvia Lake 2 mi · Raccoon Lake 3 mi · Speckledtrout Lake 3 mi · Fraser Lake 3 mi · Whitefish Lake 4 mi · Prottler Lake 4 mi · Jean Lake 4 mi · Pinetree Lake 5 mi · Mildred Lake 5 mi
See how Rock Lake stacks up: best smallmouth bass lakes in Ontario · best yellow perch lakes in Ontario · best lake trout lakes in Ontario · best lake whitefish lakes in Ontario
More water nearby: Haliburton County fishing maps (295 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.