Lake depth chart
Today's read
Recent public catches load as you reach this section.
710-acre lake near Scottish Borders. The lake tops out around 153 ft. This chart interpolates between a real shoreline and a known maximum depth. It will point you at likely water, but it is not a navigation product. Every species below gets its seasonal read from the same numbers driving the chart.
The outline encloses 708 acres, worked by 8.8 miles of shoreline. That shoreline is heavily fingered (development index 2.4) — bays, points and pockets everywhere, which multiplies the fishable edge. About 5% of the surface sits shallower than 15 ft on the modeled chart — that's the weed-and-bait zone. The basin spans about 3.6 mi end to end and 1.1 mi across at its widest. It sits in Scottish Borders. If the bite dies, Loch Skeen or Loch Skene is 6 mi to the southwest.
Spring puts brown trout in skinny water — 3 to 25 ft is the zone. Warm water sends them out to 25 to 60 ft; cold water stacks them in 5 to 35 ft. Main-lake point is the standout, a point at roughly 38 ft, rated prime for summer brown trout. Plan around after dark and early morning in the warm months. A spoon at the thermocline or a deep stickbait (night) covers the summer program.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 3 to 25 ft | dawn & dusk | open water | Stickbait off planer boards (shallow), Small spoon along mud lines |
| Summer | 25 to 60 ft | night & dawn | Main-lake point (38 ft) | Spoon at the thermocline, Deep stickbait (night) |
| Fall | 5 to 30 ft | dusk & dawn | Main-lake point (38 ft) | Jerkbait over gravel, Casting spoon |
| Winter | 5 to 35 ft | dawn | open water | Jigging spoon, Small stickbait (slow) |
Early season european perch use the shallows, holding in 3 to 12 ft. Summer is an 8 to 28 ft game here, winter a 12 to 33 ft one. The chart's best answer is Shallow bay flat — feeding flat, 6 ft, prime for spring. Best bite is early morning. Tie on a drop-shot micro plastics or a small crankbait (perch pattern) 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 (6 ft) | Small jig + curly tail, Inline spinner #1-2 |
| Summer | 8 to 28 ft | dawn | Shallow bay flat (6 ft) | Drop-shot micro plastics, Small crankbait (perch pattern) |
| Fall | 10 to 33 ft | midday | open water | Jigging spoon (small), Drop-shot on deep flats |
| Winter | 12 to 33 ft | midday & dawn | open water | Tungsten jig + maggots, Small balance jig |
Come spring, look for northern pike tight to the bank in 2 to 8 ft. They move out to 8 to 20 ft in summer and finish the year down in 5 to 15 ft. If you only fish one area, make it Shallow bay flat: a feeding flat around 6 ft that scores prime in spring. Best bite is early morning and the evening. A bucktail or a weedless spoon over cabbage is the honest summer answer here.
| 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: arctic char in 4 to 15 ft. As the season builds they drop to 20 to 60 ft, wintering in 10 to 40 ft. Top water on the chart: Shallow bay flat, a feeding flat in the 6 ft range, good in spring. Time it for early morning. Summer baits: a jigging spoon vertical or a tube jig (smelt) gets it done.
| Season | Depth | Best window | Start at | Go-to baits |
|---|---|---|---|---|
| Spring | 4 to 15 ft | midday & dawn | Shallow bay flat (6 ft) | Small casting spoon (silver/orange), Jerkbait (small) |
| Summer | 20 to 60 ft | dawn | open water | Jigging spoon vertical, Tube jig (smelt) |
| Fall | 8 to 30 ft | midday & dusk | open water | Casting spoon (orange/gold), Beadhead streamer |
| Winter | 10 to 40 ft | midday & dawn | open water | Jigging spoon (glow/silver), Tungsten jig + plastic |
St Marys Loch carries 5 mapped structure features, topping out (or rather bottoming out) at Deep basin, about 130 ft down.
St Marys Loch is about 153 ft (47 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 brown trout, european perch, northern pike, arctic char on St Marys Loch. This isn't a survey of the water — none is published for it — but an informed estimate from the species common to the region, narrowed by this water's depth, size and each species' range.
Shallow bay flat is the top-rated area: a feeding flat in about 6 ft of water that rates prime for european perch in spring. Open the map above to see every rated spot for each species and season.
For brown trout, the summer bite is best in after dark 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.
Loch Skeen or Loch Skene 6 mi · Loch Eddy 6 mi · Talla Reservoir 8 mi · Moodlaw Loch 9 mi · Headshaw Loch 13 mi · Portmore Loch 18 mi · Slipperfield Loch or Dalmahoy Loch 19 mi · Gladhouse Reservoir 20 mi · Hallhills Loch 21 mi · Rosebery Reservoir 22 mi · Edgelaw Reservoir 23 mi · Mill Loch 26 mi
See how St Marys Loch stacks up: best northern pike lakes in United Kingdom · best european perch lakes in United Kingdom · best brown trout lakes in United Kingdom · best arctic char lakes in United Kingdom
More water nearby: Scottish Borders fishing maps (7 charts). Browse all United Kingdom fishing maps. 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.