Sturgeon Lake

Where Sturgeon Lake is

Sturgeon Lake lies in the District of Thunder Bay and the District of Kenora.

How deep is Sturgeon Lake?

The deepest mapped contour on Sturgeon Lake is 79.2 meters, and the water within that boundary descends even farther. Ontario’s bathymetry record holds 389 depth contours for Sturgeon Lake.

See also Ontario's Largest and Deepest Lakes

Surveyed Depths

Ontario has surveyed the depths of several thousand of its lakes over more than half a century. Later surveys were conducted by boat with satellite positioning and produced hundreds of thousands of soundings per lake. Earlier surveys were charted by running transects across the water and drawing depth contours by hand.

Water quality

Ontario’s Lake Partner Program is a volunteer monitoring network. Participants collect water samples for phosphorus analysis and measure water clarity through the summer with a Secchi disk. Most sites are sampled for phosphorus once a year, in spring, and some several times a year between spring and fall. Phosphorus in many lakes rises through the summer, so the two kinds of average are measured on different bases.

Phosphorus is the nutrient that controls how much algae a lake can grow. A lake with little phosphorus stays clear and supports cold-water fish such as lake trout. As phosphorus rises, algae increase, the water clouds, and oxygen in the deep water falls as the algae decay. The province classifies each monitoring site by its average phosphorus:

• Oligotrophic, below 10 micrograms per litre: clear water and low algae.
• Mesotrophic, from 10 to 20: moderately productive water, with more algae and weed growth than an oligotrophic lake but rarely a bloom.
• Eutrophic, above 20: nutrient-rich water, prone to algal blooms and low oxygen at depth.

No monitoring site on Sturgeon Lake is registered with the Lake Partner Program, so no phosphorus or clarity record exists for the lake.

A Secchi disk is a white or black-and-white plate lowered on a marked line until it disappears from view. The depth at which it vanishes is the Secchi depth, a direct measure of water clarity. Clearer water gives a deeper reading.

See also Lake Water Quality and Blue-Green Algae in Ontario

Fish in Sturgeon Lake

Ontario’s aquatic resource records name 36 fish species in Sturgeon Lake.

Popular species in the province’s records

• Lake Trouttrout and whitefish
• Brook Trouttrout and whitefish
• Lake Whitefishtrout and whitefish
• Ciscotrout and whitefish
• Northern Pikepike
• Muskellungepike
• Walleyeperch
• Saugerperch
• Yellow Perchperch
• Smallmouth Basssunfish
• Rock Basssunfish
• Burbotcod

Spawning areas

Ontario maps 18 fish spawning records within the Sturgeon Lake outline, for three different species. Fifteen are records of under 100 square meters each, and the other three are mapped areas.

By number of records

By area mapped

• Lake Trout14 records100 m²
• Northern Pike3 areas100 m²
• Walleye1 records0 m²

The federal Fisheries Act prohibits the harmful alteration, disruption or destruction of fish habitat without an authorization, so a dock, dredging, infill or shoreline work at a mapped spawning area is reviewed on that basis.

Eating the fish

The 2026 Guide to Eating Ontario Fish carries consumption advice for six species taken from Sturgeon Lake, tested for contaminants at a sampling location in Thunder Bay Dist. Each figure below is the most meals a month the guide advises for a fish of that length. Where mercury sets the advice, the figure falls as the fish gets longer, because mercury accumulates over a fish’s life. A zero means the guide advises no meals of that fish at that size.

General population: adultsSensitive population: children under fifteen, women who are or may become pregnant

Fisheries Management Zone 4

Sturgeon Lake lies in Fisheries Management Zone 4. Ontario sets its fishing seasons and catch limits by zone.

Fisheries management zones around Sturgeon Lake

Zone-wide, Smelt may not be used as bait or possessed for use as bait.

Where a row reads zone-wide, the zone’s own season or limit above applies.

See also Fishing Seasons in Ontario, Zone by Zone and Fish Stocking in Ontario Lakes

Islands and names

Sturgeon Lake contains 797 islands in the Ontario Hydro Network’s outline, 46 of them over 10 hectares and 401 under a tenth of a hectare.

Official names

Ontario’s geographic names register lists 43 official names on the water and its islands: 12 islands, seventeen bays, four narrows and one point on an island. A further 3 named points stand on the mainland shore.

Bays 17

• Beidelman Bay
• Belmore Bay
• Black Bay
• Cobb Bay
• Countryman's Bay
• East Bay
• Granite Bay
• Horizontal Bay
• Jones Bay
• King Bay
• LeBeau Bay
• Marie's Bay
• Mountain Island Bay
• Nipigon Bay
• Sac Bay
• Shore's Bay
• St. Anthony Bay

Harbours, cuts and narrows 4

• Deadhorse Narrows
• Droopy Narrows
• Sturgeon Narrows
• Symmes Narrows

Points on the shore 3

• Hotel Point
• The Horn
• Trapper's Point

Nearby lakes

• Abram Lake73 km away
• Minnitaki Lake76 km away
• Pelican Lake78 km away
• Lac Seul118 km away

All lakes

Questions about Sturgeon Lake

• How deep is Sturgeon Lake?

  Its deepest charted contour is 79.2 meters, and the water within it is deeper.

• How big is Sturgeon Lake?

  Its surface covers 244.5 square kilometers and it holds 797 islands. Of its 1,060 kilometers of shoreline, 583 kilometers is the mainland shore and 477 kilometers is the shore of the islands.

• What fish are in Sturgeon Lake?

  Ontario’s aquatic resource records name 36 species, among them lake trout, walleye, smallmouth bass, northern pike, muskellunge and lake whitefish.