Theriault Lake (lac Thériault)
Theriault Lake (lac Thériault) is the 651st-largest of 4,179 named lakes in Northeastern Ontario, with 3.8 miles of charted shoreline and 1 island. The lake lies 24 km northeast of Markstay-Warren. Its 20 ft maximum depth is greater than 22% of depth-surveyed lakes in the region.
MNRF aquatic resource surveys
Fish species
Also present: Striped Bass, White Sucker
On this water
Lodges & operators 0
No operators recorded on this lake yet. Know one? It may be listed under a nearby community — browse the map.
2026 regulations
Seasons & limitsFMZ 11
| Species | Season | Sport licence | Conservation |
|---|---|---|---|
| Walleye and Sauger or any combination | Jan. 1 - 3rd Sun. in Mar. & 3rd Sat. in May - Dec. 31 | S - 4, none between 43 - 60 cm (16.9 - 23.6 in.), not more than 1 greater than 60 cm (23.6 in.) | C - 2, none between 43 - 60 cm (16.9 - 23.6 in.), not more than 1 greater than 60 cm (23.6 in.) |
| Yellow Perch | Open all year | S - 50 | C - 25 |
Compiled from MNRF Recreational Fishing Regulations open data (2026 season, zone-wide rules shown for this lake's species). Regulations change by variation order — confirm with the official FMZ 11 summary before you fish.
Eating what you catch
Consumption advisories
Recommended meals per month from Ontario's fish contaminant monitoring — ranges span the tested fish sizes.
| Species | General | Sensitive* |
|---|---|---|
| Yellow Perch | 16–32 | 8–12 |
Advisory cause across all species: Mercury.
*Women of child-bearing age and children under 15. Compiled from the MECP Guide to Eating Ontario Fish (2025 guide) — check the guide for size-specific advice before keeping fish.
Comparable trips
Similar water
Same region, overlapping species, comparable size.
- Lovering Lake3 shared species · 209 ac
- Lac Clair3 shared species · 209 ac
- Sydney Lake3 shared species · 210 ac
- Hampel Lake3 shared species · 211 ac
- Lower Twin Lake3 shared species · 214 ac
Around this water