East Graham Lake is a 604-acre lake located about one mile south of the Town of Kinbrae in Nobles County. East Graham Lake has a maximum depth of 8.0 feet, and has turbid water. East Graham Lake is considered to be one of the headwaters of the West Fork of the Des Moines River, resulting in immigration and emigration of fish from the river. East Graham Lake has historically been susceptible to low dissolved oxygen levels, as it was opened to liberalized fishing 16 times from 1952 to 1982. More recently, East Graham Lake experienced low dissolved oxygen levels during the winter of 2009-2010 and the winter of 2013-2014; however, no significant winterkills were reported. The Power House Ice Eater system replaced the old Helixor system in 2007 and continues to be operated by the Nobles County Parks Department. East Graham Lake is managed primarily for Walleye and Northern Pike and secondarily for Black Crappie. Walleye are stocked at a rate of 1000 per littoral acre, two out of three years (i.e., 2012, 2013, 2015, 2016). Northern Pike and Black Crappie have not been stocked in the last decade because they were able to maintain their populations through natural reproduction, or through immigration from connected waterbodies. East Graham Lake was surveyed the week of June 1, 2015 to monitor fish populations using three gill nets and eight trap nets.
Catch rates of Walleye on East Graham Lake have been highly variable, ranging from 3.7 per gill net in 2003 to 33.7 per gill net in 1999 and averaging 13.4 per gill net since 1986. In 2015, Walleye were captured at a rate of 8.0 per gill net, which is an increase from the 2011 catch rate of 7.3 per gill net, and was within the expected range of catch rates for similar lakes in the Windom management area (2.3 to 13.3 per gill net). Lengths of Walleye in gill nets ranged from 7.7 to 20.8 inches and averaged 13.3 inches. Eighty-six percent of the Walleye sampled in trap nets and gill nets were 12.0 to 16.0 inches in length and were age-2 fish from the 2013 fry stocking. Other year classes sampled included Walleye from 2014 (age-1, N=2) and 2011 (age-4, N=1), which were non-stocked years. The likelihood of natural reproduction is low, so these fish from non-stocked years likely emigrated from West Graham Lake which was stocked with Walleye fry in 2011 and 2014. Lengths at age were 9.2 inches at age-1, and 12.8 inches at age-2, which is slightly slower growth than what is observed on other similar lakes around the state (11.0 inches at age-1 and 14.3 inches at age-2). The 2013 year class should provide a decent angling opportunity in the near future.
The Northern Pike catch rate in East Graham Lake in 2015 was 8.3 per gill net, which is the highest recorded catch rate for this lake, and nearly four times higher than what we would expect for lakes similar to East Graham in the Windom management area. Previous catch rates have ranged from 0.0 per gill net in 1991 to 4.0 per gill net in 1999 and 2003, and have averaged 3.5 per gill net since 1986. Northern Pike have not been stocked in East Graham Lake since 1994, suggesting that this population sustains itself through natural reproduction. Several wetlands are present around East Graham Lake which would provide good spawning habitat if water levels are high enough for Northern Pike to move into them during the spawning season. Additionally, connection to the West Fork of the Des Moines River, West Graham Lake, and outflow from Fulda Lake, likely increases Northern Pike abundance. Lengths of Northern Pike captured in gill nets and trap nets ranged from 9.8 to 27.7 inches and averaged 21.4 inches. Northern Pike are aggressive fish that can easily be caught at times. Northern Pike angling on East Graham Lake should be good in the near future.
Since 2007, the Black Crappie catch rate has declined from 68.0 per trap net, to 2.6 per trap net in 2011, to 0.5 per trap net in 2015. The 2015 catch rate of 0.5 per trap net was the lowest observed catch rate on East Graham Lake and is below the expected range of catch rates for lakes in the Windom management area (0.7 to 15.3 per trap net). Lengths of Black Crappie ranged from 7.6 to 11.2 inches and averaged 10.3 inches. The decreased abundance of black crappie is likely a result of a lack of natural reproduction in recent years. Black crappie natural reproduction tends to be highly variable and is often characterized as cyclic, with strong year classes reoccurring every three to five years. Many times the abiotic conditions at the time of spawning determine success. Typically, crappies key in on wind protected bays with some emergent aquatic vegetation like cattails for reproduction. This variable and cyclic recruitment often results in a "boom-or-bust" crappie fishery, where years of increased angler catch rates are followed by years of decreased angler catch rates.
The Black Bullhead catch rate in trap nets increased from 31.0 per trap net in 2011 to 144.9 per trap net in 2015, and in gill nets increased from 62.7 per gill net in 2011 to 87.0 per gill net in 2015. The trap net catch rate exceeded the normal catch rates for similar lakes (11.5 to 132.6 per trap net), and the gill net catch rate was within the expected range of catch rates (30.3 to 150.6 per gill net). Lengths of Black Bullhead ranged from 5.1 to 13.3 inches and averaged 8.6 inches.
Catch rates of Common Carp in gill nets and trap nets were down from the 2011 survey, decreasing from 8.7 per gill net in 2011 to 3.7 per gill net in 2015, and from 9.2 per trap net in 2011 to 2.5 per trap net in 2015. Lengths of Common Carp ranged from 9.9 to 28.2 inches and averaged 17.0 inches.
The Bigmouth Buffalo gill net catch rate of 36.3 per gill net was the highest recorded catch rate on East Graham Lake. It greatly exceeded the expected range of catch rates for similar lakes (0.8 to 7.0 per gill net). Lengths of Bigmouth Buffalo ranged from 8.6 to 24.2 inches and averaged 12.0 inches. Eighty percent of gill netted Bigmouth Buffalo were between 11.0 and 13.0 inches, and only four exceeded 18.0 inches. While Bigmouth Buffalo are not a highly sought after fish by the hook and line angler, they are a native fish and prized by commercial fisherman.
The 2015 Channel Catfish catch rate of 2.7 per gill net was consistent with the 2011 catch rate of 3.3 per gill net. Channel Catfish lengths ranged from 14.2 to 19.1 inches and averaged 17.3 inches.
Other species sampled included White Sucker (N= 29), Yellow Perch (N=14), Quillback (N=3), and Yellow Bullhead (N=2).
Plants in the water and at the water's edge provide habitat, prevent erosion, and absorb excess nutrients. Shrubs, trees, and woody debris such as fallen trees or limbs provide good habitat both above and below the water and should be left in place. By leaving a buffer strip of natural vegetation along the shoreline, property owners can reduce erosion, help maintain or improve water quality, and provide habitat and travel corridors for wildlife.
Best management practices within the watershed (no-till farming, cover crops, buffer strips, targeted fertilizer application, reduced or metered tiling) would help reduce nutrients entering the lake. High nutrient and sediment input can cause algae blooms and reduce overall water quality. Any improvements in the watershed are likely to have positive impacts on the fishery.
Prepared by Jonah Dagel