Cottonwood Lake Fishing guide

Water clarity was moderate (4.0 feet) with excellent dissolved oxygen levels (9 ppm) on September 9, 2025 for Cottonwood. Shoalwater substrates include boulder, rubble, gravel, sand, and silt. The fine sediments compose most of the lake substrates. Water levels above normal during the spring and summer, but normal by fall of 2025. Submergent vegetation densities were moderate in 2025 which included mostly sago pondweed. Blue-green algae blooms were moderate during the 2025 summer and fall. Intense blue-green algal blooms are common during the summer due to agricultural, residential, municipal and golf course nutrient runoff. There are approximately 15 drain tile, culvert and storm sewer inlets that enter Cottonwood Lake. The three largest inlets are ditches that enter the southeast (County Ditch#69), north (Judicial Ditch#18) and southwest corners of the lake. An outlet dam is located along the northwest shore. The outlet structure is inadequate at preventing fish movement (i.e. Common Carp, Northern Pike and Bowfin) into Cottonwood during high water events. The outlet flows into Judicial Ditch#24, which drains into the Yellow Medicine River and eventually the Minnesota River.

Prior to 1993, angling for game fish species was limited due to frequent winterkills. Angling opportunities have increased dramatically following the 1993 reclamation and subsequent operation of aeration units in Cottonwood. Local residents have reported high shore fishing catches of small (< 22.00 inches) Northern Pike during recent years. The current southern zone Northern Pike regulation only allows the harvest of Northern Pike 24.00 inches or larger from Cottonwood Lake.

Black Bullhead abundance was moderate in 2025 (26.00 fish/gillnet). The Black Bullhead historical average gillnet catch rate is 86.24 fish/gillnet. The 2025 Black Bullhead average size was large (0.73 pounds and 10.83 inches) from gillnets. The Black Bullhead historical average weight is 0.45 pounds from gillnets for Cottonwood. The largest Black Bullhead captured was 13.43 inches in 2025.

Common Carp abundance was moderate in 2025 (3.00 fish/gillnet). The Common Carp historical catch rate is 9.41 fish/gillnet for Cottonwood. The 2025 Common Carp average size was moderate (3.36 pounds and 17.08 inches) from gillnets. The Common Carp historical average weight is 2.26 pounds from gillnets for Cottonwood.

Black Crappie were not present in the 2017, 2022 or 2025 survey nets. Black Crappie were only sampled in Cottonwood surveys during 2007 (0.44 fish/trapnet, 9.25 inches average) and 2012 (4.11 fish/trapnet, 12.83 inches average). Black Crappie adults were last stocked (632 fish, 158 pounds) into Cottonwood during 2008.

Bluegill were not sampled in the 2017, 2022 or 2025 survey nets. The Bluegill historical catch rate is 1.74 fish/trapnet for Cottonwood.

Channel Catfish were not caught in survey nets since 2007. Low numbers were caught in Cottonwood during 1997 and 2007 surveys. Channel Catfish fingerlings were first stocked into Cottonwood during 1994 (6,730 fish) and recently in 2008 (3,250 fish).

Northern Pike abundance was high in 2025 (7.00 fish/gillnet). The Northern Pike historical average catch rate is 3.94 fish/gillnet for Cottonwood. Abundant shallow in-lake habitat (sago pondweed) and inlet/outlet connections for immigration to potential spawning habitat (wetlands and river systems) have produced large year classes of Northern Pike for Cottonwood Lake. There were abundant numbers of small sized Northern Pike captured in surveys from 2002 (7.33 fish/gillnet, 1.66 pounds average weight) and 2012 (15.00 fish/gillnet, 2.30 pounds average weight). Low numbers were present in the 2017 gillnets (1.00 fish/gillnet, 1.24 pounds average weight). Moderate numbers (2.67 fish/gillnet, 2.85 pounds average weight) were present in the 2022 survey. The 2025 Northern Pike average size was small (2.03 pounds and 20.94 inches) from gillnets. Northern Pike historical average weight is 2.02 pounds from gillnets. Northern Pike growth rates were slow for ages 1-3. The 2023 and 2022 year classes comprised 57% and 43% respectively of the 2025 Northern Pike catch. The largest Northern Pike captured was 25.71 inches in 2025.

Cottonwood Lake is in the Southern Northern Pike Regulation zone which allows anglers and spearers to keep two Northern Pike daily, with a minimum size of 24.00 inches. Only one Northern Pike was captured over 24.00 inches in the 2025 gillnet survey. Local residents have recently reported high catches of small size Northern Pike with few over 24.00 inches in Cottonwood. The Northern Pike zone regulation is currently not justifiable due to slow growth and abundant numbers of small sized Northern Pike in Cottonwood Lake.

Yellow Perch abundance was moderate in 2025 (17.00 fish/gillnet). The Yellow Perch historical average catch rate is 31.54 fish/gillnet for Cottonwood. The 2025 Yellow Perch average size was large (0.55 pounds and 9.96 inches) from gillnets. The Yellow Perch historical average length is 8.44 inches. The largest Yellow Perch captured was 12.28 inches in 2025. Yellow Perch were last stocked in 2013 (8,554 yearlings, 329 pounds; 442 adults, 138 pounds).

Walleye natural reproduction has been generally insignificant based on previous surveys for Cottonwood. Walleye fry are generally stocked (160,000-250,000) every other year in Cottonwood, after a fry stocking failure or winterkill occurrence. Walleye fry (124,769 fish) were last stocked in May of 2025. Other recent Walleye fry stockings (102,000 - 250,000 fish) included 2008-2011, 2013-2014, 2016, 2018, and 2021-2025. Additionally, Walleye fingerlings and yearlings had been previously stocked into Cottonwood during late September of 2004 (12,130 fish, 715 pounds), January of 2010 (16,800 fingerlings, 700 pounds-private stocking), May of 2010 (124 yearlings/adults, 19 pounds), fall of 2011 (5,152 yearlings; 260 fingerlings; and 82 adults; 742 pounds total), fall of 2014 (29 fish, 38 pounds) and fall of 2020 (416 yearlings, 277 pounds; 69 adults, 137 pounds).

Low young of year "YOY" Walleye numbers (14.00 YOY/hour, 8.35 inches) were caught in the 2023 fall night electrofishing survey. Moderate numbers of young of year "YOY" Walleye (36.00 YOY/hour, 6.35 inches) were caught in a daytime fall electrofishing survey. YOY Walleye are probably more numerous than documented in 2022 due to daytime electrofishing being less effective than nighttime electrofishing for catching YOY Walleye. Abundant numbers of large sized YOY Walleye were captured in the 2016 (86.00 YOY/hour, 8.17 inches) and 2018 (210.00 YOY/hour, 8.33 inches) fall night electrofishing surveys. Moderate numbers of YOY Walleye (48.00 YOY/hour, 6.16 inches) were captured in the 2014 fall night electrofishing survey. No YOY Walleye were captured in the 2013 fall electrofishing survey. However, there were abundant YOY Northern Pike (102.22 YOY/hour, 7.70 inches) captured in the 2013 fall electrofishing survey. No fall YOY Walleye electrofishing surveys were conducted in 2020-2021 and 2024-2025.

Walleye abundance was high in 2025 (27.00 fish/gillnet). The Walleye historical average catch rate is 25.76 fish/gillnet for Cottonwood. The 2025 Walleye average size was moderate (1.11 pounds and 14.30 inches) from gillnets. Walleye historical average weight is 1.28 pounds from gillnets. The 2025 Walleye catch rate of quality size (15.00 inches and larger) was high (10.00 fish/gillnet). The largest Walleye captured was 21.18 inches in 2025. Walleye growth rates were fast for ages 1-5. The 2023 (fry stocked year) accounted for 74% of the 2025 Walleye gillnet catch.

Other fish species captured in 2025 included low to moderate numbers of White Sucker (1.00 fish/gillnet) and Yellow Bullhead (2.00 fish/gillnet). The average weights were 2.27 pounds and 1.05 pounds respectively for White Sucker and Yellow Bullhead.

Current fish management activities on Cottonwood include monitoring the fish population on a periodic basis, monitoring winter dissolved oxygen levels, assisting local residents and the sportsman's club with the operation of the aeration system, protecting aquatic vegetation through the permit process, assisting aquatic plant management and enforcement personnel in educating boaters and monitoring access sites for potential invasive species introductions, participating in local watershed initiatives, and stocking various fish species as warranted. Cottonwood Lake will be surveyed for all fish species in the 2027 summer and 2027 fall for YOY Walleye.