Big Birch

Big Birch Lake is a 2,107 acre lake located near Grey Eagle, Minnesota. The lake consists of an upper and lower basin, has 15.25 miles of shoreline, a maximum depth of 81 feet, and a littoral area of 642 acres. Primary management species on Big Birch Lake are Northern Pike and Walleye while secondary species include Bluegill, Largemouth Bass, and Smallmouth Bass. Night electrofishing in fall has been used to evaluate the success of natural reproduction or spring Walleye fry stocking. A spring stocking of 1,900,000 Walleye fry occurred on May 13, 2025. Prior years in the fall young of the year Walleye assessments were conducted utilizing one hour of on time. On time was increased to two hours beginning in 2020 as Big Birch Lake is included in a research study to assess the impacts of zebra mussels on Walleye recruitment. In fall 2025, electrofishing efforts were performed to evaluate fry stocking success. Fourteen young of the year Walleye were captured in 1.75 hours of sampling effort (8/hour). Historically, fall electrofishing catch rates have ranged from 0.0/hour (1994, 2019, 2020, 2023, and 2024) to 74.5/hour (2011) with a median of 16.1/hour. Young of the year Walleye fall electrofishing catch rates typically correlate well with future Walleye year class strength. Typically, fall catch rates above 35 YWAE per hour indicate good future year classes (greater than 2.0/gill net in standard surveys) whereas lower catch rates predict poorer year classes. A total of 24 yearling to adult Walleye ranged from 8.74 to 24.69 inches were captured for a catch rate of 13.7/hour. Due to low fall young of the year Walleye electrofishing catches since 2019, Walleye fry will continue to be stocked in odd numbered years , but fingerlings will be added in the fall. In even years, 642 pounds of Walleye fingerlings will be stocked by DNR, and an option will be given to the lake group to purchase an additional 642 pounds from a private producer. It is hoped that this strategy will help maintain the Walleye population at a level consistent with management goals. It is important to note that a recent infestation of Zebra Mussels may impact future Walleye populations by impacting productivity in the lake. Big Birch Lake has been included in important ongoing research to determine potential impacts of Zebra Mussels on Walleye populations in lakes in Minnesota. Other species commonly observed during sampling included Black Crappie, Bluegill, Bowfin, Brook Silverside, Hybrid Sunfish, Largemouth Bass, Pumpkinseed, Rock Bass, Smallmouth Bass, Yellow Perch, and Common Carp.

A standard survey was conducted using on Big Birch Lake in 2024 which consisted of multiple sampling efforts including: standard summer gill nets, spring panfish trap netting for Bluegill and Black Crappie, spring daytime electrofishing for bass, and fall electrofishing for juvenile Walleye. Gill netting is scheduled to occur every three years as part of a statewide study to evaluate the impacts of Zebra Mussel infestations on Walleye population dynamics. Fall electrofishing for juvenile Walleye occurs annually and is also providing data for the Zebra Mussel study. Walleye are a primary management species on Big Birch Lake. Gill net catch rates of Walleye have hovered around the management objective (6.6/lift)since 2003 with the one exception being 2010 when Walleye were sampled at a rate of 11.5/lift. The 2024 gill nets produced a catch rate of 6.67/lift. Fry stocking itself supported the fishery from 2010 to 2018. In 2019 fingerling stocking was re-initiated due to consistently low catch rates noted during fall electrofishing for juvenile Walleye. Fingerlings were most recently stocked in 2022 and fingerling stocking is now scheduled to take place during even numbered years and fry stocking will be practiced during odd numbered years. Fry and fingerling stocked Walleye both contribute significantly to the population and little or no natural reproduction has been evident. Aging results from 2024 indicate the strongest year classes were produced in 2022 when fingerlings were stocked and 2019 when both fry and fingerlings were stocked. Over 50% of the total gill net catch were Age 2 fish. Age 3 fish were also well represented and originated from fry stocking. Over 90% of the catch was Age 5 or younger. The dominance of younger fish in the population is not unwelcome and is further indication of recently successful stocking events. Walleye growth is good with Age 3 fish averaging 18.6 inches during the summer gill net survey. Fall night electrofishing has been completed on an annual or biennial basis since 1994 on Big Birch Lake to evaluate young of the year Walleye abundance. In fall 2024, electrofishing efforts were performed to evaluate fry stocking success. A total of 9 Walleye ranging from 12.8 to 23.4 inches were captured in the 2024 fall electrofishing. No young of the year (YWAE) Walleye were captured. Catch rates have been at or below 1 fish per hour each fall since 2019. Young of the year Walleye fall electrofishing catch rates typically correlate well with future Walleye year class strength. Generally, fall catch rates above 35 YWAE per hour indicate good future year classes whereas lower catch rates often predicted poorer year classes. However, an absence or minimal catch in fall electrofishing has not necessarily equated to an absence of a year class in subsequent gill net surveys. Fall electrofishing in 2021 produced just a single YWAE but the 2024 gill nets caught 19 Age 3 fish indicating a significant year class. It is unknown to what degree the observed shift in habitat at fall electrofishing sites has impacted sampling efficiency for young-of-year Walleye. Vegetation has been much more prevalent at many of the sampling sites over the past several years and this has corresponded with low YWAE catch rates. The impacts of the concurrent infestation with Zebra Mussels on Walleye fry stocking success are also unknown. However, YWAE catch rates in fall electrofishing have remained low since Zebra Mussels became established. Gill net catch rates for Northern Pike have shown evidence of a decreasing trend since 2010. From 2003 to 2018 pike catch rates remained elevated between 8.1 and 14.1 per gill net. The gill net catch in 2021 fell to 5.8/lift and 2024 gill nets indicated a modern record low of 2.67/lift. Maintaining pike densities at the currently lower level is desirable for prey base species such as Yellow Perch and may enhance survival of stocked Walleye. Since the elimination of the 24 to 26 inch protected slot in 2015 the prevalence of pike over 30 inches has declined with none observed in the 2021 gill nets and one noted in 2024. Despite the lack of these larger pike, mean size exceeded 23 inches in 2021 and 2024 and the percentage of fish over 24 inches has well surpassed the management objective of 15% in both surveys. The percentage of pike residing in the zonal regulation protected slot of 22 to 26 inches has also increased to the highest levels on record topping out at 42.5% in the 2024 gill nets. Yellow Perch were observed at a rate of 10.5 per gill net lift in 2024, the highest rate since 2010. Low catch rates have been more characteristic since 2003. The increased abundance noted in 2024 may be in response to the lower pike abundances recently found. Higher numbers of perch are usually a positive for Walleye management as perch are a preferred prey species. Most of the perch sampled in the 2024 gill nets were in the 5.5 to 6.5 inch range with few exceeding 8 inches. A total of 50 Smallmouth Bass were caught in gill nets in 2024 resulting in a catch rate of 3.33/lift. The 2024 catch rate was the highest on record. Gill net catch rates dating back to 1967 never exceeded 2/lift. Smallmouth Bass are also evaluated using daytime electrofishing. In 2024 the electrofishing effort captured 54 fish for a catch rate of 33/hour which was similar to the 2018 catch rate of 35 fish/hour. Large bass dominated both the gill net and electrofishing samples in 2024. Bass averaged 15.6 inches in the gill nets and 16.5 inches in the electrofishing catch. Smallmouth greater than 15 inches comprised 70% of the gill net sample and 87% of the electrofishing catch. The Largemouth Bass electrofishing catch rate was 60.4/hour in 2024 with a total of 99 bass caught. Large bass dominated the length frequency as fish over 15 inches accounted for 54% of the sample. Though gill nets are not the primary tool for assessing Largemouth Bass populations it should be noted that 60 bass were collected in the 2024 gill nets resulting in a catch rate of 4/lift. The gill netted bass tended to be smaller than electrofished bass and averaged 11.2 inches in length. Spring trap netting conducted in May produced a sample of 713 Bluegill. The 2024 size structure was characterized by fish over 7 inches constituting 19.8% of the catch and fish longer than 8 inches making up 2.4%. The only previous spring trap netting targeting sunfish occurred in 2018 catching a total of 229 Bluegills. In 2018 the percentage of Bluegills over 7 and 8 inches was 30 and four respectively. No Bluegills over 9 inches have been present in May trap nets. Though not considered a primary tool for assessing Bluegill populations the 2024 gill nets provided a sample of 225 fish. The 2024 gill net size structure proved more favorable than the spring trap nets. More than 40% of the gill net sample consisted of fish over 7 inches, 16.5% were over 8 inches and 6 fish greater than 9 inches were observed. Gill nets in 2021 failed to show this contrast in size structure as only 8% exceeded 7 inches. Aging data indicated that most age groups displayed normal growth rates with Age 4 fish averaging about 5 inches and Age 6 fish averaging 7 inches. Growth appeared to slow for most individuals as they neared 8 inches. Spring trap netting caught a total of 20 crappies in 2018 and 19 crappies in 2024 suggesting limited value for assessing population structure. Spring electrofishing in 2021 and 2024 produced similar crappie catches of 23 fish (2021) and 28 fish (2024). These daytime electrofishing efforts were both dominated by larger fish with ten fish over 12 inches measured in 2021 and seven in 2024. Gill nets set in 2024 procured a sample of 107 crappies providing useful information. Large catches of crappie have not been typical for the gill nets in Big Birch Lake. The 2024 sample showed a wide range of sizes from 4.6 to 13.94 inches. Fish over 10 inches comprised 17% of the catch and eight fish over 12 inches were observed. Crappies between 7.5 and 8.5 inches made up a little more than ½ of the sample. Age and growth data indicated crappies grow fast attaining 11 inches by Age 4 and 12 inches by Age 5. The large number of 7.5-8.5 inch fish noted in the gill nets likely represents a relatively strong 2022 year class. Hybrid Sunfish and Pumpkinseeds were fairly prominent in the 2024 spring trap nets. The Hybrid Sunfish sample totaled 118 fish of which 31% exceeded 7 inches and 14% surpassed 8 inches. A similar percentage (31%) of Pumpkinseeds were over 7 inches with the largest fish measuring 9 inches. A total of 66 Pumpkinseeds were netted. No Cisco were caught in any gear ion 2024 however Big Birch Lake has historically supported Ciscoes and a 2017 vertical gill net collected 11 fish ranging in size from 3.5-14.5 inches. The last time Cisco were observed in a summer gill nets was in 2018 when a single specimen was collected.

Big Birch Lake is a 2,107-acre lake located near Grey Eagle, Minnesota. The lake consists of an upper and lower basin, has 15.25 miles of shoreline, a maximum depth of 81 feet, and a littoral area of 642 acres. Primary management species on Big Birch Lake are Northern Pike and Walleye while secondary species include Bluegill, Largemouth Bass, and Smallmouth Bass. Night electrofishing in fall has been used to evaluate the success of natural reproduction or spring Walleye fry stocking. A spring stocking of 1,900,000 Walleye fry occurred on May 5, 2023. Fall night electrofishing has been completed on an annual or biennial basis since 1994 on Big Birch Lake to evaluate young of the year Walleye abundance. Fry stocking commenced in 1996 on a biennial basis (every other year) through 2000. Fry were stocked during odd numbered years from 2001 to 2005 and were backed up with contingency fingerling stocking if fry survival was found to be poor. Even year fry stocking took place from 2006 to 2010 and fry have been stocked on an annual basis since that time. A stocking rate of roughly 3,000 fry per littoral acre was employed until 2016, then the use of a lower rate (1,500 per littoral acre) was incorporated in alternating years to evaluate if a lower density stocking rate would meet management goals. Results suggested the higher stocking rate produced higher fall catch rates. Prior fall young of the year Walleye assessments were conducted utilizing one hour of on-time. On-time was increased to two hours beginning in 2020 as Big Birch Lake is included in a research study to assess the impacts of zebra mussels on Walleye recruitment. In fall 2023, electrofishing efforts were performed to evaluate fry stocking success. No young of the year Walleye were captured in 1.5 hours of sampling effort. Historically, fall electrofishing catch rates have ranged from 0.0/hour (1994, 2019 and 2020) to 74.5/hour (2011) with a median of 16.1/hour. Young of the year Walleye fall electrofishing catch rates typically correlate well with future Walleye year class strength. Typically, fall catch rates above 35 YWAE per hour indicate good future year classes (greater than 2.0/gill net in standard surveys) whereas lower catch rates predict poorer year classes. A total of 8 yearling Walleye ranging from 9.25 to 12.52 inches were captured for a catch rate of 5.33/hour. Due to low fall young of the year Walleye electrofishing catches since 2016, the stocking strategy has been changed on Big Birch Lake. Walleye fry will continue to be stocked in odd numbered years. In even years, 642 pounds of Walleye fingerlings will be stocked by DNR, and an option will be given to the lake group to purchase an additional 642 pounds from a private producer. It is hoped that this strategy will help maintain the Walleye population at a level consistent with management goals. It is important to note that a recent infestation of Zebra Mussels may impact future Walleye populations by impacting productivity in the lake. Big Birch Lake has been included in important ongoing research to determine potential impacts of Zebra Mussels on Walleye populations in lakes in Minnesota. Other species commonly observed during sampling included Black Crappie, Bluegill, Bowfin, Brook Silverside, Hybrid Sunfish, Largemouth Bass, Pumpkinseed, Rock Bass, Smallmouth Bass and White Sucker.

Based on Minnesota DNR survey data, anglers target Smallmouth Bass, Black Crappie, Largemouth Bass, Hybrid Sunfish, and Walleye in Big Birch. See the full species list above for catch rates, size structure, and quality scores.

Minnesota DNR records list public access for Big Birch. Check the DNR LakeFinder page for the launch type and directions before you go.

Big Birch has a maximum depth of 81 feet and a mean depth of 28 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Big Birch is from 2024.

Yes — Big Birch has confirmed zebra mussel. Clean, drain, and dry your equipment to avoid spreading invasives to other waters.