The trap net catch indices for bluegill and largemouth bass are above their third regional quartile. The yellow perch catch index is below the first regional quartile for gillnets. Northern pike ranged from 5 to 9 years of age. Growth increments for all ages except age 2 are normal. The growth increment for age 2 ranged from 32 to 46 percent slower for other fish that were greater than 6 years old. Bluegill ranged from 3 to 7 years of age. Forty- one percent of the fish aged were 3 years old. Growth for the second and third increments is slower than normal. Largemouth bass ranged from 1 to 6 years of age. A strong year class was established in 1985. Growth increments for 2 and 3 year old fish are 23 to 28 percent slower than normal. The bluegill population has dramatically increased in abundance from 15.0 per trap net in 1978 to 62.3/trap net in 1987, an increase of 315 percent. The pumpkinseed population has increased 217 percent. The variation in catch rate for other species is not significant for the amount of sampling.
","lengths":{},"surveyDate":"1987-08-06","surveySubType":"Re-Survey","surveyID":"113254","headerInfo":{"wb_type":"Lake","survey_type":"Re-Survey","county":"Aitkin","wb_name":"Blue","wb_alt_name":"","survey_id":"113254","wb_id":"01018100","id_date":"1987-08-06"}},{"surveyDate":"2009-10-26","lengths":{"BLG":{"maximum_length":5,"minimum_length":3,"fishCount":[[3,3],[5,3]]},"YEP":{"maximum_length":8,"minimum_length":8,"fishCount":[[8,1]]},"BKT":{"minimum_length":11,"maximum_length":11,"fishCount":[[11,1]]},"NOP":{"minimum_length":10,"maximum_length":29,"fishCount":[[10,1],[15,1],[26,1],[29,1]]},"LMB":{"minimum_length":10,"maximum_length":10,"fishCount":[[10,1]]}},"headerInfo":{"survey_type":"Special Assessment","wb_type":"Lake","id_date":"2009-10-26","wb_alt_name":"","wb_name":"Blue","county":"Aitkin","wb_id":"01018100","survey_id":"4260923828351028"},"surveyID":"4260923828351028","surveySubType":"Special Assessment","surveyType":"Targeted Survey","narrative":"Blue Lake is a two-story lake located in western Aitkin County two miles southwest of the town of Aitkin. A two story lake by definition is one that is able to support coldwater fish species along with coolwater and warmwater species at the same time. The lake has a surface area of 47 acres and a maximum depth of 106 feet. The surrounding land is a mixture of rolling hills and bogs. The hills and ridges are covered with mixed hardwoods, primarily maples and oaks. Most of the shoreline is privately owned with the north end of the lake being a wooded pasture and the rest of the lake platted into home sites. The public access is a carry-in access located on the south side of the northeast bay. Blue Lake is popular for anglers seeking a quiet place to fish, away from the hustle and bustle of the more easily accessed lakes. The carry-in access limits most anglers to either fishing from shore or from a small boat or canoe. With most of the shoreline being privately owned, angling opportunities from shore are limited to the area adjacent to the public access.
\n
\nBlue Lake is managed as a stream trout lake and is stocked annually with rainbow trout or brook trout yearlings to provide a put and take fishery for local anglers. Rainbow trout have been stocked most frequently, however brook trout were stocked in 2008 and 2009 on a trial basis to evaluate their performance in the system. Brook trout will continue to be stocked until 2011 or 2012 when rainbow trout become available again. These trout are usually \"keeper\" size when they are stocked and usually range in size from 9 - 11 inches. Early in the season, Blue Lake can provide some good fishing, particularly for the shore angler. Warm and cool water species available to anglers include northern pike, largemouth bass and bluegill. Although pike are not very abundant, there are some memorable sized fish present in the system. Surveys of the fishery conducted in 2004 and in 2009 have indicated there are very few trout surviving through the summer and into the fall. Some combination of mortality due to angler harvest and northern pike predation are the suspected causes. Hatchery raised trout are quite susceptible to fishing mortality, and predation by northern pike likely depletes any remaining stock.
\n
Blue Lake is a two-story lake, able to support both cold-water and warm-water fish species, located in western Aitkin County two miles from the City of Aitkin. The lake has a surface area of close to 50 acres and a maximum depth of 106 feet. The surrounding land is a mixture of rolling hills of mixed maple and oak hardwoods interspersed with wetlands. There is a carry-in type public access located on the south shore of the easternmost bay that requires a portage of about 100 yards down a crushed rock path from the parking area and negotiating a steep bank with stairs near the lake.
\n
\nBlue Lake is stocked annually with rainbow trout yearlings to provide a put and take fishery for local anglers but it is not a designated stream trout lake. Anglers can fish the lake following standard angling license requirements, but can only harvest trout if they possess a trout stamp validation. Brook trout were stocked from 2008 to 2010 on a trial basis to evaluate their performance in the system, but produced limited results. Rainbow trout are stocked in the spring as keeper-sized fish and usually range from 9 - 11 inches. Blue Lake can provide some good fishing early in the season, particularly for shore anglers, which is a unique opportunity in the Aitkin area.
\n
\nWarm-water species available to anglers include northern pike, largemouth bass and bluegill. Although pike are not very abundant, the lake can produce some memorable sized fish. Recent fisheries surveys conducted in the fall indicate very few trout are surviving through the summer. Some combination of mortality due to angler harvest and northern pike predation are the suspected causes. Hatchery raised trout are quite susceptible to fishing mortality, and predation by northern pike likely depletes any remaining stock.
Blue Lake is a two-story lake, able to support both cold-water and warm-water fish species, located in western Aitkin County two miles from the City of Aitkin. The lake has a surface area of close to 50 acres and a maximum depth of 106 feet. The surrounding land is a mixture of rolling hills of mixed maple and oak hardwoods interspersed with wetlands. There is a carry-in type public access located on the south shore of the easternmost bay that requires a portage of about 100 yards down a crushed rock path from the parking area and negotiating a steep bank with stairs near the lake.
\n
\nBlue Lake is stocked annually with Rainbow Trout yearlings to provide a put and take fishery for local anglers, but it is not a designated stream trout lake. Anglers can fish the lake following standard angling license requirements, but can only harvest trout if they possess a trout stamp validation. Kamloops Rainbow Trout have been stocked since 2011, and appear to be working better than any other strain/species used since the early 1990s. Currently they are stocked in the spring and fall as catchable-sized fish that usually range from 9 - 11 inches. By fall, most of spring stocked fish have grown to 11-14 inches. Blue Lake can provide some good fishing in both the openwater and ice fishing seasons, including from shore, which is a unique opportunity in the Aitkin area.
\n
\nWarm-water species available to anglers include Northern Pike, Largemouth Bass and Bluegill. Although pike are not very abundant, the lake can produce some memorable sized fish such as the 37.6 inch pike observed in this survey.
\n
\nHistorical records show that Blue Lake was stocked with Lake Trout in 1937 and that a population existed up until at least 1954. In September of 2016 the TDO3 (temperature at 3 mg/l dissolved oxygen) was determined to be 5.7 C, which is considered good for Tullibee survival. Though there are no Tullibee present in Blue Lake, Lake Trout are a cold water species and have similar habitat requirements where optimum conditions are about 5 ppm of oxygen at 10 C. The profile shows overall oxy-thermal habitat is still sufficient for Lake Trout from about 25 -35 feet in late summer. There are no plans to stock Blue Lake with Lake Trout at this time, however they may be considered in the future as it appears habitat conditions are still favorable.
\n
The trap net indices for northern pike, pumpkinseed, bluegill, largemouth bass and yellow perch were below the lake class 20 first quartiles.
"},{"narrative":"Blue Lake is a two-story lake, able to support both cold-water and warm-water fish species, located in western Aitkin County two miles from the City of Aitkin. The lake has a surface area of close to 50 acres and a maximum depth of 106 feet. The surrounding land is a mixture of rolling hills of mixed maple and oak hardwoods interspersed with wetlands. There is a carry-in type public access located on the south shore of the easternmost bay that requires a portage of about 100 yards down a crushed rock path from the parking area and negotiating a steep bank with stairs near the lake.\n\nBlue Lake is stocked annually with rainbow trout yearlings to provide a put and take fishery for local anglers, but it is not a designated stream trout lake. Anglers can fish the lake following standard angling license requirements, but can only harvest trout if they possess a trout stamp validation. Kamloops rainbow trout have been stocked since 2011, and appear to be working better than any other strain/species used since the early 1990s. They are stocked in the spring as catchable-sized fish that usually range from 9 - 11 inches. By fall, most have grown to 11-14 inches. Blue Lake can provide some good fishing in both the openwater and ice fishing seasons, including from shore, which is a unique opportunity in the Aitkin area.\n\nWarm-water species available to anglers include northern pike, largemouth bass and bluegill. Although pike are not very abundant, the lake can produce some memorable sized fish such as the 40 inch pike observed in this survey. \n\nA temperature - dissolved oxygen (TDO) profile was collected on September 9, 2016 to determine if the amount of thermal habitat available is sufficient for lake trout survival. Historical records show that Blue Lake was stocked with lake trout in 1937 and that a population existed up until at least 1954. The TDO3 (temperature at 3 mg/l dissolved oxygen) was determined to be 5.7 C, which is considered good for tullibee survival. Though there are no tullibee present in Blue Lake, lake trout are a cold water species and have similar habitat requirements where optimum conditions are about 5 ppm of oxygen at 10 C. The profile shows overall oxy-thermal habitat is still sufficient for lake trout from about 25 -35 feet in late summer. There are no plans to stock Blue Lake with lake trout at this time, however they may be considered in the future as it appears habitat conditions are still favorable.
","fishCatchSummaries":[{"quartileWeight":"1.7-3.2","gearCount":2,"species":"NOP","totalCatch":3,"CPUE":"1.50","averageWeight":"9.24","totalWeight":12568,"quartileCount":"2.0-8.0","gear":"Standard gill nets"},{"totalWeight":308,"quartileCount":"N/A","averageWeight":"0.23","CPUE":"0.15","gear":"Standard trap nets","quartileWeight":"N/A","totalCatch":3,"species":"HSF","gearCount":20},{"gearCount":2,"totalCatch":10,"species":"RBT","quartileWeight":"N/A","gear":"Standard gill nets","averageWeight":"0.76","CPUE":"5.00","quartileCount":"N/A","totalWeight":3444},{"gear":"Standard trap nets","quartileCount":"7.9-37.7","totalWeight":2117,"CPUE":"0.80","averageWeight":"0.29","species":"BLG","totalCatch":16,"gearCount":20,"quartileWeight":"0.1-0.2"},{"quartileWeight":"0.3-0.9","gearCount":20,"totalCatch":13,"species":"LMB","averageWeight":"0.63","CPUE":"0.65","quartileCount":"0.5-2.0","totalWeight":3704,"gear":"Standard trap nets"},{"gear":"Standard trap nets","CPUE":"0.10","averageWeight":"0.79","quartileCount":"N/A","totalWeight":719,"gearCount":20,"species":"NOP","totalCatch":2,"quartileWeight":"N/A"},{"averageWeight":"0.78","CPUE":"4.00","quartileCount":"0.6-5.5","totalWeight":2839,"gear":"Standard gill nets","quartileWeight":"0.2-0.6","gearCount":2,"species":"YEB","totalCatch":8},{"averageWeight":"0.74","CPUE":"2.10","totalWeight":14024,"quartileCount":"N/A","gear":"Standard trap nets","quartileWeight":"N/A","gearCount":20,"species":"RBT","totalCatch":42},{"averageWeight":"0.12","CPUE":"3.00","quartileCount":"N/A","totalWeight":332,"gear":"Standard gill nets","quartileWeight":"N/A","gearCount":2,"species":"HSF","totalCatch":6},{"gear":"Standard trap nets","quartileCount":"1.1-4.7","totalWeight":60,"CPUE":"0.05","averageWeight":"0.13","species":"PMK","totalCatch":1,"gearCount":20,"quartileWeight":"0.1-0.2"},{"gear":"Standard gill nets","averageWeight":"0.22","CPUE":"0.50","quartileCount":"N/A","totalWeight":102,"gearCount":2,"species":"BLG","totalCatch":1,"quartileWeight":"N/A"},{"quartileWeight":"0.1-0.2","totalCatch":4,"species":"YEP","gearCount":2,"quartileCount":"1.5-18.5","totalWeight":699,"averageWeight":"0.39","CPUE":"2.00","gear":"Standard gill nets"},{"quartileCount":"0.5-1.7","totalWeight":776,"CPUE":"2.50","averageWeight":"0.34","gear":"Standard gill nets","quartileWeight":"0.5-1.0","totalCatch":5,"species":"LMB","gearCount":2},{"gear":"Standard trap nets","totalWeight":3025,"quartileCount":"2.0-8.1","CPUE":"0.35","averageWeight":"0.95","species":"YEB","totalCatch":7,"gearCount":20,"quartileWeight":"0.4-0.7"}],"surveyType":"Standard Survey","surveySubType":"Standard Survey","headerInfo":{"wb_type":"Lake","survey_type":"Standard Survey","county":"Aitkin","wb_alt_name":"","wb_name":"Blue","survey_id":"13731610232869012","wb_id":"01018100","id_date":"2016-10-12"},"surveyID":"13731610232869012","lengths":{"HSF":{"fishCount":[[4,5],[5,2],[6,1],[8,1]],"maximum_length":8,"minimum_length":4},"NOP":{"minimum_length":9,"maximum_length":39,"fishCount":[[14,1],[16,1],[29,1],[39,1],[9,1]]},"YEB":{"fishCount":[[10,3],[11,9],[12,1],[13,2]],"maximum_length":13,"minimum_length":10},"BLG":{"minimum_length":6,"maximum_length":8,"fishCount":[[6,3],[7,8],[8,6]]},"PMK":{"fishCount":[[5,1]],"minimum_length":5,"maximum_length":5},"RBT":{"minimum_length":10,"maximum_length":17,"fishCount":[[10,1],[11,5],[12,28],[13,8],[14,2],[15,7],[17,1]]},"LMB":{"minimum_length":5,"maximum_length":15,"fishCount":[[10,1],[11,2],[12,1],[15,2],[5,1],[7,3],[8,4],[9,4]]},"YEP":{"minimum_length":7,"maximum_length":11,"fishCount":[[10,1],[11,1],[7,1],[9,1]]}},"surveyDate":"2016-10-12"},{"lengths":{"NOP":{"minimum_length":12,"maximum_length":36,"fishCount":[[12,2],[13,1],[16,2],[17,1],[28,1],[29,1],[34,1],[36,1]]},"HSF":{"fishCount":[[3,3],[4,1],[5,6],[6,2],[8,1]],"minimum_length":3,"maximum_length":8},"YEB":{"fishCount":[[10,4],[11,3],[8,1],[9,5]],"minimum_length":8,"maximum_length":11},"BLG":{"fishCount":[[2,1],[3,6],[4,10],[5,14],[6,3],[7,1],[8,1]],"minimum_length":2,"maximum_length":8},"RBT":{"fishCount":[[16,1]],"minimum_length":16,"maximum_length":16},"LMB":{"fishCount":[[10,2],[12,1],[13,1],[16,2],[17,1],[5,2],[6,2],[8,1],[9,2]],"maximum_length":17,"minimum_length":5},"PMK":{"fishCount":[[5,2],[6,2]],"minimum_length":5,"maximum_length":6},"YEP":{"fishCount":[[10,2],[6,1],[7,3],[8,4]],"minimum_length":6,"maximum_length":10}},"surveyDate":"2025-10-20","surveySubType":"Standard Survey","surveyID":"20212529332094035","headerInfo":{"survey_type":"Standard Survey","wb_type":"Lake","id_date":"2025-10-20","survey_id":"20212529332094035","wb_id":"01018100","wb_name":"Blue","wb_alt_name":"","county":"Aitkin"},"surveyType":"Standard Survey","fishCatchSummaries":[{"totalCatch":3,"species":"NOP","gearCount":2,"quartileWeight":"1.7-3.2","gear":"Standard gill nets","totalWeight":4551,"quartileCount":"2.0-8.0","averageWeight":"3.34","CPUE":"1.50"},{"gear":"Standard trap nets","averageWeight":"0.12","CPUE":"0.55","totalWeight":579,"quartileCount":"N/A","gearCount":20,"totalCatch":11,"species":"HSF","quartileWeight":"N/A"},{"quartileWeight":"0.1-0.2","species":"BLG","totalCatch":33,"gearCount":20,"quartileCount":"7.9-37.7","totalWeight":1573,"CPUE":"1.65","averageWeight":"0.11","gear":"Standard trap nets"},{"totalCatch":1,"species":"RBT","gearCount":2,"quartileWeight":"N/A","gear":"Standard gill nets","quartileCount":"N/A","totalWeight":880,"averageWeight":"1.94","CPUE":"0.50"},{"quartileWeight":"0.1-0.3","gearCount":20,"totalCatch":1,"species":"YEP","averageWeight":"0.30","CPUE":"0.05","totalWeight":136,"quartileCount":"0.3-0.8","gear":"Standard trap nets"},{"CPUE":"0.65","averageWeight":"0.90","totalWeight":5314,"quartileCount":"0.5-2.0","gear":"Standard trap nets","quartileWeight":"0.3-0.9","gearCount":20,"totalCatch":13,"species":"LMB"},{"CPUE":"0.35","averageWeight":"3.34","quartileCount":"N/A","totalWeight":10614,"gear":"Standard trap nets","quartileWeight":"N/A","gearCount":20,"species":"NOP","totalCatch":7},{"gear":"Standard gill nets","totalWeight":679,"quartileCount":"0.6-5.5","averageWeight":"0.50","CPUE":"1.50","species":"YEB","totalCatch":3,"gearCount":2,"quartileWeight":"0.2-0.6"},{"quartileCount":"N/A","totalWeight":288,"CPUE":"1.00","averageWeight":"0.32","gear":"Standard gill nets","quartileWeight":"N/A","totalCatch":2,"species":"HSF","gearCount":2},{"totalCatch":4,"species":"PMK","gearCount":20,"quartileWeight":"0.1-0.2","gear":"Standard trap nets","totalWeight":321,"quartileCount":"1.1-4.7","averageWeight":"0.18","CPUE":"0.20"},{"averageWeight":"0.16","CPUE":"1.50","quartileCount":"N/A","totalWeight":215,"gear":"Standard gill nets","quartileWeight":"N/A","gearCount":2,"totalCatch":3,"species":"BLG"},{"gear":"Standard gill nets","totalWeight":1198,"quartileCount":"1.5-18.5","CPUE":"4.50","averageWeight":"0.29","totalCatch":9,"species":"YEP","gearCount":2,"quartileWeight":"0.1-0.2"},{"totalCatch":1,"species":"LMB","gearCount":2,"quartileWeight":"0.5-1.0","gear":"Standard gill nets","totalWeight":625,"quartileCount":"0.5-1.7","CPUE":"0.50","averageWeight":"1.38"},{"quartileWeight":"0.4-0.7","gearCount":20,"totalCatch":10,"species":"YEB","averageWeight":"0.62","CPUE":"0.50","totalWeight":2807,"quartileCount":"2.0-8.1","gear":"Standard trap nets"}],"narrative":"Blue Lake is a two-story lake, able to support both cold-water and warm-water fish species, located in western Aitkin County two miles southwest of Aitkin. The lake has a surface area of 53 acres and maximum depth of 106 feet. The surrounding land is a mixture of rolling hills of mixed maple and oak hardwoods interspersed with wetlands. A carry-in public access is located on the south shore of the easternmost bay that requires a portage down a crushed rock path from the parking area and negotiating a steep bank with stairs near the lake. A standard survey was conducted on Blue Lake the week of 10/20/25 to assess the fishery.
\n
\nBlue Lake is stocked annually with Rainbow Trout yearlings in spring (4000) and in fall (900) to provide a put-and-take fishery for anglers, but is not a designated stream trout lake. Additionally, larger surplus brood stock Trout are often stocked when they are available from the hatcheries. In addition to the Rainbow Trout fishery, Splake (Brook Trout x Lake Trout hybrid) were stocked in spring 2025 to supplement a statewide shortage of Kamloop strain Rainbow Trout. Anglers can fish the lake following standard angling license requirements but can only harvest Trout if they possess a Trout stamp validation. Kamloop Rainbow Trout have been stocked since 2011, but as of 2025, Kamloop strain production has been discontinued, and Arlee strain Rainbow Trout will be stocked going forward. Rainbows are currently stocked in the spring and fall as catchable-sized fish that usually range from 9 - 11 inches. By fall, most spring-stocked fish have grown to 11 - 14 inches. Blue Lake can provide some good fishing in both the open water and ice fishing seasons, including from shore, which is a unique opportunity for the Aitkin area.
\n
\nOnly one Rainbow Trout was captured in gill nets during the 2025 survey, and no Trout were captured in trap nets. The lone Rainbow Trout sampled was 17.0 inches long. Catch rates of other species sampled in gill nets and trap nets were minimal, with Bluegill, Hybrid Sunfish, Largemouth Bass, Northern Pike, Pumpkinseed, and Yellow Bullhead all captured at a rate of less than 2.0 per net, regardless of gear type.
\n
\nOther notable captures included a 34.5 and 36.0 inch Northern Pike, an 8.6 inch Bluegill, and a 17.4 inch Largemouth Bass, indicating some fish in Blue Lake are reaching preferred and memorable sizes. It is unclear as to why more Rainbow Trout or Splake were not captured.
\n
\nIn August 2025, a temperature and oxygen profile was collected, along with the temperature at 3 mg/l dissolved oxygen (TDO3) to determine the amount of cold-water habitat in the lake. The TDO3 was determined to be 6.5 degrees C, which is considered very good for cold-water species, including stream trout, Tullibee, and even Lake Trout.
\n