Koop

Koop Lake is a 59-acre, natural environment lake located five miles southwest of Avon in central Stearns County. Koop Lake has a maximum depth of 52 feet and water clarity of 10 feet. Forty-five percent of the lake is considered littoral (less than 15 feet deep). Koop Lake supports a diverse aquatic vegetation community. Much of the shoreline is lightly developed and protected by emergent plants. Principal game fish species include northern pike, largemouth bass, and panfish. Koop Lake, last surveyed in 1987, has received low priority for management because it has no public access. Day-time electrofishing for largemouth bass was conducted for the first time in Koop Lake on May 18, 2010. Largemouth bass were sampled at about half the average catch rate for other Montrose Area lakes with fish up to 20 inches in length. The average length and weight was 16 inches and 2.7 pounds. The largemouth sample was dominated by larger, older fish. Eighty percent of the catchable size (greater than eight inches) largemouth measured greater than 15 inches. The northern pike catch (4.5/gill net) was similar to the 1987 survey and near the average for lakes with similar characteristics. Northern pike ranged in length from 19-30 inches with an average length and weight of 23 inches and three pounds. Four-year classes were sampled during the survey with the 2008 (age-2) year class comprising 50% of the sample. Northern pike in Koop Lake grew to a length of 24 inches in six years. Forty-four percent of northern pike sampled in gill nets were greater than 24 inches in length. Despite the relatively fast growth rates of northern pike in Koop Lake, few yellow perch were sampled. Typically, yellow perch provide an important source of forage for northern pike. Bluegills sampled in Koop Lake were mostly small (less than six inches) but a few fish over seven inches in length were found. Natural reproduction was sufficient with the 2007 (age-3), 2006 (age-4) and 2005 (age-5) year classes making up 70% of the sample. Bluegills in Koop Lake grew to seven inches in eight years. Few black crappie were sampled in the 2010 survey. Most black crappie sampled were around nine inches in length. Multiple year classes were sampled during the survey with the 2005 (age 5) year class comprising the majority of the sample. Black crappies from Koop Lake grew to a length of eight inches in five years. Few carp and bullheads were sampled during this survey. Carp populations in Koop Lake have been a concern for local residents in the past. Other species sampled in low numbers during the survey included: bowfin, hybrid sunfish, and pumpkinseed sunfish.

Gamefish species include Northern Pike, Pumpkinseed, Bluegill, hybrid sunfish, Largemouth Bass, and Black Crappie. Other fish, species present in Koop Lake are Bowfin, Common Carp, Golden Shiner, Blacknose Shiner, White Sucker, Black, Yellow and Brown Bullhead and Yellow Perch. Northern pike were captured at a rate of 5.0/ gill net, which is near the local median of 5.2/ gill net. They ranged in length from 16 to 24 in. And the average weight was 1.9 pounds. Age classes ii-v were present with age 4 fish comprising 45% of the sample. Growth was average. Bluegill were sampled at a rate of 41.8/trap net. They were abundant, but average length was only 5.0 inches. However, growth rates were average at all ages sampled. Age classes 1, 2, 4 and 5 were present but age class 3 was inexplicably absent. Classes 1 and 5 comprised 69% of the sample. A total of 13 Largemouth Bass were collected. The trap net catch was above the expected range of similar lakes. Several year classes were present and lengths ranged from 6 to 16 inches. Growth was slow at ages 1-3, progressing to average thereafter. The Black Crappie population appeared to be abundant. Trap net catch was 21.3/net, above the expected range for lakes with similar characteristics. Total lengths ranged from 4 to 10.5 in. Age classes 1-6 were present with age 1 being most abundant. Composite growth was average. Bowfin, Yellow Bullhead and Yellow Perch catch rates were all near their respective local medians while White Sucker numbers were above the expected range. Observations of Common Carp suggest that their abundance is actually greater than the trap net catch would imply.

Based on Minnesota DNR survey data, anglers target Northern Pike, Largemouth Bass, Hybrid Sunfish, Pumpkinseed, and Yellow Perch in Koop. See the full species list above for catch rates, size structure, and quality scores.

We don't have a confirmed public access point on record for Koop. Check the DNR LakeFinder page for current access details before you go.

Koop has a maximum depth of 52 feet and a mean depth of 15.7 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Koop is from 2010. Surveys this old should be treated with some caution — fish populations change over time.

No invasive species are on record for Koop in Minnesota DNR data. Always clean, drain, and dry your equipment to help keep it that way.