Manitoulin District, Ontario
Lake Wolsey

- Surface
- 22.9 km²
- Shoreline
- 25 km
- Islands
- 0
- Max depth
- 25.1 m
- Soundings
- 47,571
Where Lake Wolsey is
Lake Wolsey lies in the District of Manitoulin, with shoreline in the Municipality of Gordon / Barrie Island and the Township of Burpee and Mills.
How deep is Lake Wolsey?
Lake Wolsey reaches a maximum recorded depth of 25.1 meters, determined from 47,571 soundings.
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.
Lake Wolsey has 13 Lake Partner monitoring sites. Eight have reported phosphorus for the three or more years the province requires before a status is assigned. Five of those sites are classified oligotrophic and three mesotrophic.
| Site | Location | Years | Samples a year | Last sampled | Classification |
|---|---|---|---|---|---|
| 6883/4 | Sein-SP4, S-central Reference | 5 | 1 | 2018 | oligotrophic |
| 6883/6 | Sein-Deep spot | 5 | 1 | 2018 | oligotrophic |
| 6883/5 | Sein-SP5-S end | 4 | 1 | 2018 | oligotrophic |
| 6883/1 | Sein-SP2, N end | 3 | 1 | 2018 | oligotrophic |
| 6883/18 | 30M South of Cage | 3 | 2 | 2018 | mesotrophic |
| 6883/19 | 30M North of Cage | 3 | 2 | 2018 | mesotrophic |
| 6883/2 | Sein-S end | 3 | 1 | 2014 | oligotrophic |
| 6883/20 | 30M East of Cage | 3 | 2 | 2018 | mesotrophic |
The longest record is held by site 6883/4 at Sein-SP4, S-central Reference, with phosphorus sampled once a year over 5 years to 2018. Its long-term mean phosphorus concentration is 7.6 micrograms per litre, within the oligotrophic band, which extends to 10.
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.
Lake Wolsey Weather
The weather page for Lake Wolsey carries the forecast over the water, wave heights across the lake, and the modelled water temperature.
Water temperature
No provincial monitoring station records water temperature on Lake Wolsey. The LastLake model computes the temperature of its surface water for each day from the daily mean air temperature at Environment Canada’s Gore Bay-Manitoulin climate station, 8 kilometers from the lake, or the next nearest station when its record is incomplete, and from the lake’s area of 2,290 hectares and its mean depth. The province’s records give no mean depth for Lake Wolsey; the model uses 7.7 meters, estimated from its deepest mapped contour.
Each day’s figure carries the model’s typical error for that month on lakes of the same size. The figure in the chart below is the temperature near the surface, away from the shoreline. Bays, shallows and water deeper below the surface differ in temperature. Temperature is not measured when ice covers the lake. The weather page for Lake Wolsey carries the model’s figures for the past weeks and the coming week.
See also Lake Water Temperature in Ontario
Fish in Lake Wolsey
Ontario’s aquatic resource records list no species for Lake Wolsey. The province’s other records for the lake name two species, northern pike and rainbow trout. They appear in the records below.
Popular species in the province’s records
Rainbow Trouttrout and whitefish
Northern Pikepike
Spawning areas
Ontario maps 3 fish spawning records within the Lake Wolsey outline, for two different species, and all of them are mapped below.
By number of records
By area mapped
- Northern Pike2 areas2.1 ha
- Rainbow Trout nursery1 area1.4 ha
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.
Fisheries Management Zone 14
Lake Wolsey lies in Fisheries Management Zone 14. Ontario sets its fishing seasons and catch limits by zone.
Fisheries management zones around Lake Wolsey
| Species | Open season | Sport licence | Conservation licence |
|---|---|---|---|
| Atlantic Salmon | Open all year | 1 | 0 |
| Brown Trout | Open all year | 5 | 2 |
| Channel Catfish | Open all year | 12 | 6 |
| Crappie | Open all year | 30 | 10 |
| Lake Herring (Cisco) | Open all year | 25 | 12 |
| Lake Trout | Jan. 1 – Sept. 30 & Dec. 1 – Dec. 31 | 2 | 1 |
| Lake Whitefish | Open all year | 12 | 6 |
| Largemouth and Smallmouth Bass or any combination | 4th Sat. in June – Nov. 30 | 3 | 1 |
| Muskellunge | 3rd Sat. in June – Dec. 15 | 1, must be greater than 137 cm (54 in.) | 0 |
| Northern Pike | Jan. 1 – Mar. 1 & May 1 – Dec. 31 | 2 in one day Possession limit 4, not more than 1 greater than 86 cm (34 in.) | 1 in one day Possession limit 2, not more than 1 greater than 86 cm (34 in.) |
| Pacific Salmon | Open all year | 5 | 2 |
| Rainbow Trout | Open all year | 2 | 1 |
| Sunfish | Open all year | 50 | 25 |
| Walleye and Sauger or any combination | Jan. 1 – Mar. 1 & May 1 – Dec. 31 | 2 in one day Possession limit 4, none between 41 – 56 cm (16.1 – 22 in.), not more than 1 greater than 56 cm (22 in.) | 1 in one day Possession limit 2, none between 41-56 cm (16.1 – 22 in.), not more than 1 greater than 56 cm (22 in.) |
| Yellow Perch | Open all year | 25 in one day Possession limit 50 | 12 in one day Possession limit 25 |
See also Fishing Seasons in Ontario, Zone by Zone and Fish Stocking in Ontario Lakes
Lake Wolsey Ice Fishing
An ice hut on Lake Wolsey must be removed by March 15. The province sets dates for ice hut removal as a safety measure to ensure huts are removed before thawing occurs. One date applies to an entire fisheries management zone (FMZ). Lake Wolsey lies within FMZ 14.
An ice hut must also be removed before the ice breaks up, whether or not that date has passed. The deadline clears huts from the ice ahead of the thaw and does not close the fishing season.
Registration is required in FMZ 14 for an ice hut built of anything other than fabric, and for a fabric tent covering seven square meters or more. Registration is free, and the number is displayed on the outside of the hut.
Ice conditions
No public record reports the thickness or the condition of the ice on Lake Wolsey on any given day. Ontario publishes ice safety guidance for anyone going out on the ice, at ontario.ca.
See also Lake Ice in Ontario and When the Lakes Will Freeze This Winter
Nearby lakes
- Lake Kagawong17 km away
- Mindemoya Lake27 km away
- Lake Manitou42 km away
- Lauzon Lake48 km away
Questions about Lake Wolsey
- How deep is Lake Wolsey?
Its maximum recorded depth is 25.1 meters.
- How big is Lake Wolsey?
Its surface covers 22.9 square kilometers, with 25 kilometers of shoreline.
Lake guides
- Lake Ice in Ontario
- Lake Water Levels in Ontario
- Lake Water Temperature in Ontario
- Fishing Seasons in Ontario, Zone by Zone
- Fish Stocking in Ontario Lakes
- Ontario's Largest and Deepest Lakes
- Lake Water Quality and Blue-Green Algae in Ontario
- Boat Launches on Ontario Lakes
- When the Lakes Will Freeze This Winter
Looking at a property on Lake Wolsey?
Depth and water quality are two records out of many. Our Rural & Cottage Buyer’s Report gathers what the public record holds about one specific address: shore road allowance, road access, wells, flood mapping, Crown land, wetlands and more, read and checked by a person before it is sent.
Where these figures come from
- Depth, shoreline, islands and named places: Ontario Ministry of Natural Resources bathymetry and the Ontario Hydro Network, © King’s Printer for Ontario, Open Government Licence – Ontario.
- Phosphorus and water clarity: Ontario Lake Partner Program, Ministry of the Environment, Conservation and Parks, Open Government Licence – Ontario. Extract built 2026-10-06.
- Aerial photography: Ontario Imagery Web Map Service, © King’s Printer for Ontario, Open Government Licence – Ontario, drawing this frame from Central Ontario Orthophotography Project 2021 and Sentinel 2 2025, satellite.
- Official names: Geographic Names Ontario, Ministry of Natural Resources, Open Government Licence – Ontario.
- Lake outline and municipal boundaries: Ontario Hydro Network and Ontario municipal boundary records, Ministry of Natural Resources, Open Government Licence – Ontario.
- Surface water temperature: LastLake model, on the daily air temperatures of Environment and Climate Change Canada’s climate stations and its forecast. Data Source: Environment and Climate Change Canada.
- Fish species: Ontario Aquatic Resource Area records. Spawning areas: Ontario Fish Activity Area records. Both Ministry of Natural Resources, Open Government Licence – Ontario.
- Seasons and limits: Ontario recreational fishing regulations data, Ministry of Natural Resources, Open Government Licence – Ontario.
- Zone boundaries: Fisheries Management Zone, Ministry of Natural Resources, Open Government Licence – Ontario.
- Fish plates: Duane Raver, U.S. Fish and Wildlife Service; Timothy Knepp, U.S. Fish and Wildlife Service. All public domain.
- Ice hut removal dates and registration: Ontario fishing regulations, read September 2026.