Lower Buckhorn Lake

Where Lower Buckhorn Lake is

Lower Buckhorn Lake lies in the County of Peterborough, with shoreline in the Township of Selwyn and the Municipality of Trent Lakes.

How deep is Lower Buckhorn Lake?

The deepest mapped contour on Lower Buckhorn Lake is 11.0 meters, and the water within that boundary descends even farther. The chart is drawn from 32 depth contours recorded in Ontario’s transect survey.

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.

Lower Buckhorn Lake has 7 Lake Partner monitoring sites. Five have reported phosphorus for the three or more years the province requires before a status is assigned. All are classified mesotrophic.

The longest record is held by site 6990/1 at Heron Island, with phosphorus sampled several times a year between spring and fall over 22 years to 2024. Its long-term mean phosphorus concentration is 16.94 micrograms per litre, within the mesotrophic band, which runs from 10 to 20.

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.

The 103 clarity readings at site 6990/1 give a median Secchi depth of 3.6 meters.

Median Secchi depth by year at site 6990/1

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

Lower Buckhorn Lake Weather

The weather page for Lower Buckhorn Lake carries the forecast over the water, wave heights across the lake, the modelled water temperature, and the water level.

Lower Buckhorn Lake weather

Water temperature

Ontario’s aquatic resource records class Lower Buckhorn Lake as a warm-water lake, with a mean depth of 3.5 meters against its maximum of 11.

A lake separates into layers through the summer where it is deep enough. Sunlight and wind warm and mix the upper few meters, and beneath a band of rapid cooling, the thermocline, the water stays cold. A shallow lake mixes to the bottom instead and warms through, sooner in spring and later into autumn.

No provincial monitoring station records water temperature on Lower Buckhorn Lake. The weather page for Lower Buckhorn Lake carries the LastLake model’s surface water temperature for each day of the coming week. The province’s longest in-water record is kept on eight research lakes near Dorset, sampled since 1976. A reading is taken at the surface, at one meter, at each meter to seven and then every two meters to the bottom, about every two weeks through the open-water season and about monthly under ice. The record holds 5,240 readings at a depth of one meter.

At one meter the eight lakes track one another closely. On a day when several were sampled, the warmest and the coolest lake differed by about one degree in every month of the year, and a 12 meter deep lake and a 37 meter deep lake read within 0.2 degrees of each other from June to October. The weather of the year, and not the lake, sets most of the width of the band below.

Water temperature at a depth of one meter (eight lakes near Dorset, ON)

How depth changes the temperature

The chart below is the province’s record on Harp Lake, 37 meters deep, drawn as the median temperature at each depth for each month over 49 years. In July the water at one meter is 23 degrees, at five meters 15, at seven meters 9, and from 13 meters to the bottom under 6. By October the warm layer has deepened to seven meters and cooled to 11 degrees. In February the whole column sits between 1 and 4 degrees under the ice, coldest at the top.

A shallower lake in the same record warms sooner. Heney Lake, six meters deep, reads about 1.8 degrees warmer than Harp Lake at one meter from January to May, 0.8 degrees warmer from June to August, and the same or cooler from September.

See also Lake Water Temperature in Ontario

Lower Buckhorn Lake Water Level

Parks Canada measures the level of Lower Buckhorn Lake at a gauge on the lake, on the Trent-Severn Waterway, and posts one reading each weekday. The record below holds every reading since 1 January 2026, set against Parks Canada’s average, highest and lowest level for each day of the year.

Readings are provisional, posted by Parks Canada on weekdays, and are not intended for flood warning.

Fish in Lower Buckhorn Lake

Ontario’s aquatic resource records name 28 fish species in Lower Buckhorn Lake.

Popular species in the province’s records

• Muskellungepike
• Walleyeperch
• Yellow Perchperch
• Smallmouth Basssunfish
• Largemouth Basssunfish
• Black Crappiesunfish
• Rock Basssunfish
• Pumpkinseedsunfish
• Bluegillsunfish
• Brown Bullheadcatfish
• Common Carpminnow

Stocking history

Ontario’s stocking records for Lower Buckhorn Lake run from 1977 to 1989 and hold 25 releases. Muskellunge account for most of the fish: 328,035 released in twelve of the years between 1977 and 1989. The last recorded release was 20,000 muskellunge frys in 1989.

The province’s record of stocking for recreational fishing, kept from 2016, lists no release into Lower Buckhorn Lake.

Fisheries Management Zone 17

Lower Buckhorn Lake lies in Fisheries Management Zone 17. Ontario sets its fishing seasons and catch limits by zone.

Fisheries management zones around Lower Buckhorn Lake

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

Lower Buckhorn Lake Ice Fishing

An ice hut on Lower Buckhorn Lake must be removed by March 1. 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). Lower Buckhorn Lake lies within FMZ 17.

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 17 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 In / Out Date

No ice record is kept on Lower Buckhorn Lake. The province’s nearest long record covers eight lakes near Dorset, about 92 kilometers away. It holds a date for every winter since 1975, observed by eye and from cameras set on the shore.

On those eight lakes the median date of complete ice cover is December 7 and the median date of complete ice loss is April 20, a median season of 134 days.

The date the ice forms has moved later through the record: a November 26 average across 1971 to 1980, and December 11 across 2011 to 2020. The date it leaves has moved by less than a day each decade over the same period. The two charts below are drawn to one scale of 26 days, so they can be read against each other.

Ice in date (eight lakes near Dorset, ON)

Ice out date (eight lakes near Dorset, ON)

Ice conditions

No public record reports the thickness or the condition of the ice on Lower Buckhorn Lake 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

Getting on the water

Six access marks are mapped on Lower Buckhorn Lake.

See also Boat Launches on Ontario Lakes

Islands and names

Lower Buckhorn Lake contains 136 islands in the Ontario Hydro Network’s outline, one of them over 10 hectares and 82 under a tenth of a hectare. Eight of them lie mostly inside wetland the province’s Wetland With Significance dataset maps as marsh, open water or unclassified wetland. The largest of these, at 1.9 hectares, falls inside the Mississauga River Mouth Wetland.

Official names

Ontario’s geographic names register lists 19 official names on the water and its islands: 12 islands, two bays, one rock and one river. A further 13 named points stand on the mainland shore.

Bays 2

• Black Duck Bay
• Deer Bay

Shoals and rocks 1

• Tobico Rock

Points on the shore 13

• Black Point
• Craft Point
• Davis Point
• Freeborn Point
• Hall Point
• Johnsons Point
• Long Pine Point
• Millage Point
• Monroe Point
• Pearson Point
• Tanner Point
• Traynor Point
• Wood Wharf Point

Communities on the lake 3

• Buckhorn
• Deer Bay
• Victoria Springs

Nearby lakes

• Lovesick Lake5 km away
• Big Bald Lake8 km away
• Sandy Lake9 km away
• Clear Lake9 km away

All lakes

Questions about Lower Buckhorn Lake

• How deep is Lower Buckhorn Lake?

  Its deepest charted contour is 11 meters, and the water within it is deeper.

• How big is Lower Buckhorn Lake?

  Its surface covers 12.5 square kilometers and it holds 136 islands. Of its 90 kilometers of shoreline, 56 kilometers is the mainland shore and 34 kilometers is the shore of the islands.

• What fish are in Lower Buckhorn Lake?

  Ontario’s aquatic resource records name 28 species, among them walleye, smallmouth bass, largemouth bass, muskellunge, yellow perch and black crappie.

• Is the water clear?

  All five monitoring sites with a phosphorus status are classified mesotrophic, the middle of the province’s three bands.

• Is there a public boat launch?

  No boat launch on Lower Buckhorn Lake is marked in the records this page draws on.