Hatchery Fact Sheet - Glenwood
- Seasonal, cool water facility
- Species produced: Walleye
- Year Established: 1904
The Glenwood Hatchery was established in 1920.
Why was it established? To produce walleye fry.
What is the general technology used for the hatchery? Gravity feed spring water, steady supply at 48 degrees year round.
Has the technology been modified since establishment? Water heaters have been added to manipulate incubation rates.
In general, fish management tools fall into one of four categories:
- protecting and restoring habitats and water quality;
- monitoring the fishery;
- regulating the harvest;
- stocking; and
- public education.
Lake surveys and research provide the information used to select appropriate management tools.
Minnesota has more walleye, walleye lakes, and walleye anglers than any other state. Each year, anglers harvest about 3.5 million walleye.
The best way to maintain walleye numbers is to protect critical habitats. Shore land zoning and related laws aid fish by controlling development and protecting spawning sites and aquatic plants that fish use for cover.
Stocking is another management tool used. Minnesota’s cool water hatcheries produce 2 - 5 million walleye fingerlings and millions of fry each year. Stocking can provide walleye fishing in lakes that lack spawning habitats but can otherwise support walleye. Stocking is also effective for lakes that have been “rehabilitated” or occasionally winterkill. Like any tool, stocking must be used appropriately. If misused, it will be ineffective or possibly harmful to existing fish populations. Stocked walleye may compete for food with other game fish, particularly largemouth or smallmouth bass.
Stocking a lot of small fish does not guarantee catching a lot of big fish. Fish managers estimate only 4 percent of the annual statewide walleye catch comes from stocked fish. The rest is the result of natural reproduction.
Loss of habitat, pollution, and increasing fishing pressure continue to be the biggest issues in walleye management. Everyone must work to improve water quality, control runoff and waterfront development, and maintain aquatic vegetation. Anglers, in addition, will need to comply with regulations and harvest only what they intend to use, for Minnesota to maintain a quality fishery.
Walleyes begin spawning in Minnesota lakes and streams in April as water temperatures approach 45 degrees F. At this time, DNR, Fisheries staff capture wild, adult walleye that are ready to spawn. Eggs from female walleye and milt from males are gently removed and combined to yield fertilized eggs. Fertilized eggs are then transferred to State hatcheries and placed in incubation jars where water is circulated through the jars to gently suspend the eggs. In two to three weeks young walleye (fry) hatch from the eggs. The Glenwood Hatchery facility may incubate up to a maximum capacity of 810 quarts or approximately 90 million eggs. Typically 55 - 65% of these eggs will hatch to produce 40-55 million fry. After hatching, the fry swim out of the jars and are delivered to holding tanks.
Fry yielded from hatchery operations are then stocked directly into area fishing lakes or transferred to approximately 3,000 acres of rearing ponds where the fry are raised to a fingerling size (4-8 inches). Fingerlings are subsequently harvested in September and October by workers and stocked into lakes to fulfill annual Area, Regional, and statewide fingerling stocking quotas.
Science Informing Management
What types of research help with management decisions for this hatchery? Evaluating the success of fry and fryling stockings. Evaluation of artificial spawning habitat.
What other factors are involved with management decisions involving this hatchery? Funding priorities, rearing pond quality/availability, legislative directives, and public wants.
What types of research or other science activities occur along with the activities in this hatchery? Stocking evlauations, genetic performance evaluations.
How does the data collected and/or research conducted at this hatchery inform/affect fisheries managers and fisheries habitats? Helps to determine optimal stocking rates.
TOURS & VISITS
Seasonal Tours Available, Reservations Required
We are unable to give tours to casual visitors due to staffing limitations.