Fish released, 2025

4.76 million1,309 releases, recreational stocking record

Waterbodies stocked, 2025

1,227recreational stocking record

Most releases, 2016 to 2025

Brook trout6,768 releases into 1,238 waterbodies

Historical record

160,304releases, 1905 to 2015, every purpose

Lakes with a page

246 of 265with a release on record, 1915 to 2025

Stocked since 2016

51 lakesof the lakes with a page, recreational record

What Is Fish Stocking?

Fish stocking is the release of hatchery-raised fish, or of fertilized eggs, into a lake or river. Ontario’s stocking records name, for each release, the waterbody, the year, the species, the life stage of the fish and the number released.

The province stocks for two broad reasons. The first is fishing: stocking creates fisheries in lakes where a species does not reproduce, supports longer seasons or larger catch limits in some waters, and places fish where anglers can reach them easily. The second is conservation: stocking rebuilds depleted populations and returns species to waters that lost them, including Atlantic salmon to Lake Ontario and the bloater, a deepwater cisco that disappeared from Lake Ontario during the twentieth century.

Ontario is divided into twenty fisheries management zones, the areas the province sets its fishing rules by. Each zone has a fisheries management plan, and the plan decides which species are stocked and in which waters.

Stocking Purposes

The historical record names the purpose of a release in a field of its own. Across the province, 84,807 of its 160,304 releases leave that field empty, and among the lakes tabled here the first release with a purpose recorded is in 1974. A release can carry two purposes, such as rehabilitation and assessment together, and is counted under each.

Stocking Licences

A licence from the province is required to put live fish into Ontario waters, whether the stocking is done by the province, by one of its partners or by a private operator, and wherever the fish come from. A pond is exempt when it lies wholly within privately owned land, off any regional flood plain, with no connection or outflow to natural waters.

Ontario’s Fish Stocking Program

The province states that its program raises fish at nine fish culture stations and stocks about 8 million fish a year into about 1,200 waterbodies. It names eleven species: Atlantic salmon, aurora trout, bloater, brook trout, brown trout, Chinook salmon, lake trout, rainbow trout, splake, lake whitefish and walleye.

The province’s open record of recreational stocking lists 1,309 releases in 2025, totalling 4.76 million fish in 1,227 waterbodies. From 2016 to 2025 it holds between 1,194 and 1,334 releases a year, and 2,124 waterbodies received at least one release across those years.

That record holds only stocking done for recreational fishing. Stocking for rehabilitation or research since 2016 is left out of it, and the province refers questions about that stocking to its district offices. The program’s own figure of about 8 million fish a year includes both.

Species in the Recreational Record

Brook trout lead the record, with 6,768 releases into 1,238 waterbodies from 2016 to 2025. Brook trout are native to Ontario. Splake follow, with 2,473 releases into 431 waterbodies; splake is a hybrid of brook trout and lake trout produced in hatcheries. Rainbow trout and lake trout were each released into 228 waterbodies.

Walleye and Chinook salmon are released in fewer, larger batches: walleye in 163 releases totalling 6.43 million fish, and Chinook salmon in 32 releases totalling 5.65 million. Aurora trout, a cold-water trout native to a small number of lakes in northeastern Ontario, were released into eight waterbodies.

Fish Species Stocked in Ontario Lakes

Of the 265 lakes the tables here cover, 246 have at least one release on record, and together they hold 11,878 releases from 1915 to 2025. Lake trout, muskellunge, walleye and smallmouth bass account for 9,681 of them.

Lake Trout

Lake trout releases into the lakes tabled here number 4,365, across 157 lakes, from 1930 to 2025. The most are recorded for Lake Simcoe with 310, Lake Manitou with 236 and Bark Lake with 110. A lake trout release is recorded in every decade from the 1930s to the 2020s, and 27 of these lakes have one since 2016.

Muskellunge

Muskellunge releases into the lakes tabled here number 2,277, across 68 lakes, from 1946 to 2015. The most are recorded for Rice Lake with 149, Pigeon Lake with 136 and Lovesick Lake with 121. The 1950s hold the most muskellunge releases, 662, and the most recent is recorded in 2015.

Smallmouth and Largemouth Bass

Smallmouth bass releases into the lakes tabled here number 1,455, across 171 lakes, from 1915 to 1988. The most are recorded for Big Rideau Lake with 47, Lake Simcoe with 43 and Lake Manitou with 39. The 1950s hold the most, 690, and the most recent is recorded in 1988. Largemouth bass releases number 448 across 73 lakes, with the most in the 1950s and the most recent in 1988.

Walleye

Walleye releases into the lakes tabled here number 1,584, across 143 lakes, from 1925 to 2025. The most are recorded for Lake of the Woods with 140, Bobs Lake with 49 and Lake Kagawong with 41. Walleye releases continue into the recreational record, with eighteen of these lakes stocked since 2016.

Lake Whitefish and Lake Herring

Lake whitefish releases into the lakes tabled here number 511, across twelve lakes, from 1946 to 2025. The most are recorded for Lake Simcoe with 304, Lake of the Woods with 158 and Mary Lake with 20. Since 2016 the recreational record holds lake whitefish releases for Lake Simcoe. Lake herring, also called cisco, were released into ten of these lakes, the most recent in 1959.

Fish Stocking Over Time

The historical record holds 2,608 releases in 1946 and 281 in all the years before it together. Releases reach their highest count in 1953, at 4,701, and the 1950s hold more than any other decade.

Averaged by decade, the historical record holds 3,496 releases a year in the 1950s, 2,548 in the 1960s, 1,792 in the 1970s, 1,929 in the 1980s, 1,761 in the 1990s and 2,060 in the 2000s. From 2016, the recreational record alone holds between 1,194 and 1,334 a year.

In the lakes tabled here, the species shift over the same years. Muskellunge and smallmouth bass releases are both most numerous in the 1950s, and since 2000, lake trout account for 56 percent of all releases into these lakes. Among releases with a recorded purpose, the most frequent is supplemental in the 1970s to the 1990s, rehabilitation in the 2000s and put-grow-and take in the 2010s.

Stocked Lakes With the Longest Records

Lake Simcoe has a release recorded in each of the 80 years from 1946 to 2025, 781 releases in all. Lake Muskoka has a release in 77 years and Lake Manitou in 75.

The Lake Simcoe record holds 310 releases of lake trout, 304 of lake whitefish and 93 of muskellunge. The earliest release into any lake tabled here is into Sand Lake (Leeds and Grenville) in 1915.

Lakes Stocked Since 2016

Fifty-one of the lakes tabled here appear in the recreational stocking record since 2016, and 28 of them have a release in 2025. Lake trout were released into 27 of them, walleye into eighteen, splake into five, lake whitefish into one and brook trout into one.

The table holds recreational stocking alone. A lake stocked since 2016 only for rehabilitation or research is absent from it.

Trout Stocking in Ontario Lakes

In 2025 the recreational stocking record lists brook trout releases into 679 waterbodies, splake into 244, lake trout into 143, rainbow trout into 141 and brown trout into 31. A waterbody can receive more than one species.

Among the lakes tabled here, lake trout were released since 2016 into Bark Lake, Bigwind Lake, Blackstone Lake, Crane Lake, Crystal Lake, Dotty Lake, Halls Lake, Kashagawigamog Lake, Lake Bernard, Lake Manitou, Lake Muskoka, Lake Talon, Lake Vernon, Long Lake (Timiskaming District), Loughborough Lake, Maple Lake, Mary Lake, Moore Lake, Muskrat Lake, Onaping Lake, Peninsula Lake, Red Horse Lake, Red Lake, Sand Lake (Parry Sound District), Silver Lake, Star Lake and Turtle Lake. Splake were released into Clear Lake (Parry Sound District), Dog Lake (Frontenac County), Nepahwin Lake, Otter Lake (Leeds and Grenville) and Stewart Lake. Brook trout were released into Kennisis Lake.

Earlier releases reach many more of these lakes. Brook trout are recorded for 87 of the lakes tabled here, the most recent in 2022, and rainbow trout for 56, the most recent in 2015. Each lake’s page lists its releases by species and year.

Stocked Lakes by Region

Every stocked lake tabled here, grouped by region. The year beside each name is the year of its most recent recorded release, and each lake’s page lists its releases in full.

How to Read a Stocking Record

Each release in the record is one row, and each row names a waterbody, a year, a species, a life stage and a number of fish. The historical record adds the purpose, the strain the fish descend from and the station that raised them.

This row records 3,500 lake trout released into Lake Muskoka in 2015 as yearlings, with the purpose recorded as supplemental. It is one of 128 releases recorded for the lake.

Life Stages

The life stage records how old the fish were when released, and the historical record defines each stage by age. Numbers differ widely between stages: the median release into the lakes with a page is 750,000 eggs, 30,000 fry, 2,000 fingerlings or 3,000 yearlings.

Species and Strain

The species is named as the province records it. Among the lakes tabled here, four releases name a group of fish, catfishes, perches and sunfishes, in place of one species, and one names no species at all. A strain is the brood stock a hatchery fish descends from, and where the historical record names one, it names it by the lake or island the stock came from.

Where the Stocking Records Are Published

• Fish ON-Line. The province’s Fish ON-Line map searches waters by the species stocked and by place, and shows each water’s stocking with its fishing regulations, sanctuaries and access points.
• Fish stocking data for recreational purposes. The recreational record on the Ontario Data Catalogue, from 2016, updated yearly.
• Historical fish stocking data. The historical record on the Ontario Data Catalogue, 1905 to 2015, with the purpose, strain and rearing station of each release.
• District offices. The Ministry of Natural Resources refers questions about stocking for rehabilitation or research to its district offices.
• Lake pages. Each lake page lists the releases joined to its lake in its fish section, with species, years and numbers of fish.

Common Questions