Big Gull Lake Depth Map & Best Fishing Spots

Two Basins, Two Characters

Big Gull Lake stretches 21 km through the Canadian Shield and is really two lakes joined by a narrow channel. The east basin is deep and rocky with a maximum depth of 85 feet (26 metres). The west basin — historically called Little Gull Lake — is shallower with an average depth under 4 metres and sparse weed growth.

Depth Profile

The lake's overall statistics from GPS Nautical Charts: 5,979 acres of surface area, 88 km of shoreline, and an average depth of 12.9 feet (3.9 metres). The deepest point sits in the east basin near the centre of the lake.

The east basin has a well-defined thermocline in summer, typically settling between 5 and 8 metres. Below the thermocline, water temperature drops sharply — walleye and lake whitefish hold near this transition zone, especially on hot days when surface temperatures push above 22°C.

Best Fishing Spots by Species

Walleye

Target the east basin. In spring (opener through June), walleye feed aggressively in the shallows after spawning — rocky points and shoals between 3–6 metres are prime. By midsummer, move deeper to the thermocline zone (5–8 metres). Fall sees walleye push back to the shoals for the best fishing of the year. The 40–50 cm slot size in FMZ 18 means you keep the eaters and release the breeders.

Smallmouth Bass

Rocky shorelines and island points throughout the east basin. Smallmouth love structure — look for boulders, rock ledges, and submerged points. They're aggressive feeders from the June opener through September. Drop-shot rigs and tubes are consistently effective.

Largemouth Bass

Head to the west basin (Little Gull Lake) where sparse weed growth provides the cover largemouth prefer. Shallow bays with lily pads, fallen timber, and weed edges are the top spots. Topwater lures at dawn and dusk produce explosive strikes.

Northern Pike

Also concentrated in the west basin and the weedy bays of the east basin. Pike ambush from weed edges — cast spinnerbaits or large swimbaits along the transition between weeds and open water. Spring is the best season for trophy pike when they're still shallow after spawning.

Yellow Perch

Open year-round with a generous 50-fish sport limit. Perch schools move through the shallows near docks and sandy beaches — perfect for kids. You can catch them right off the dock at Island View Retreat.

FMZ 18 Regulations Quick Reference

Gear and Rentals

Camp's Bay Marina — located right next to Island View Retreat — rents boats from $99 to $219 per day and sells bait, tackle, and fishing licenses. Island View Retreat includes 2 fishing kayaks, 2 canoes, and 2 paddleboards with every stay.