Big Spunk

A targeted survey of nearshore fish species in Big Spunk Lake was conducted on September 5-7, 2023, by Index of Biological Integrity (IBI) Program staff. Ten sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where possible. Backpack electrofishing was completed at ten sampling stations, but four stations were sampled from the boat due soft sediments and steep drop offs. Similarly, a 50-foot seine was used to sample five stations, a 15-foot seine was used at one station, and deep, soft sediments prevented the use of seines at four sampling stations. Nearshore sampling captured 22 species of fish including seven species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, Least Darter, Rock Bass, and Pugnose Shiner) and two that are tolerant of disturbance (i.e., Fathead minnow, and Green Sunfish). A concurrent summer trap net survey was also conducted by IBI Program staff. Nine trap nets were set along the shoreline in locations that encompassed multiple habitat types. Trap net sampling captured ten species of fish, including one that is intolerant of disturbance (i.e., Rock Bass) and one tolerant species (i.e., Green Sunfish). Bluegill comprised a majority of the catch by number, whereas Yellow Bullhead, Bowfin, and Northern Pike comprised a majority by biomass. The nearshore and trap net data were combined with gill net data from a June 2023 survey to describe the fish community and provide a fish-based IBI (FIBI) score. The FIBI uses fish community data to measure a lake's health, and the types of fish species present can help identify any stressors that may be negatively affecting the lake environment. In Minnesota lakes, certain fish species cannot survive without clean water and a healthy habitat (e.g., Blackchin Shiner, Least Darter, and Rock Bass), while other species are tolerant of degraded conditions (e.g., Black Bullhead and Green Sunfish). The FIBI score, composed of several fish community diversity and composition metrics, indicates the overall health of a lake by comparing it to what is expected for a healthy lake. For additional information on the FIBI, search for "lake index of biological integrity" on the mndnr.gov website. Results from this survey indicate that the fish community in Big Spunk Lake is healthy as indicated by an FIBI score that exceeds the impairment threshold determined for similar lakes. These results are similar to the previous assessment which determined Big Spunk Lake was fully supported aquatic life use based on the FIBI. The recent survey results will be considered when the biological health of the lake is assessed during the Mississippi (Sartell) River Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency.

A targeted survey of nearshore fish species in Big Spunk Lake was conducted on July 13th, 2023, by Sauk Rapids Area Fisheries staff. Ten sampling sites were evenly spaced around the lake, and each was sampled by backpack electrofishing and seining with a 50-foot or 15-foot seine, where possible. Backpack electrofishing was completed at ten sampling stations, but four stations were sampled from the boat due soft sediments and steep drop offs. Similarly, a 50-foot seine was used to sample three stations, a 15-foot seine was used at two stations, and deep, soft sediments prevented the use of seines at five sampling stations. Nearshore sampling captured 19 species of fish including seven species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, Least Darter, Rock Bass, and Pugnose Shiner) and one that is tolerant of disturbance (i.e., Green Sunfish). The nearshore data were combined with gill net and trap net data from a June 2023 survey to describe the fish community and provide a fish-based IBI (FIBI) score. The FIBI uses fish community data to measure a lake's health, and the types of fish species present can help identify any stressors that may be negatively affecting the lake environment. In Minnesota lakes, certain fish species cannot survive without clean water and a healthy habitat (e.g., Blackchin Shiner, Least Darter, and Rock Bass), while other species are tolerant of degraded conditions (e.g., Black Bullhead and Green Sunfish). The FIBI score, composed of several fish community diversity and composition metrics, indicates the overall health of a lake by comparing it to what is expected for a healthy lake. For additional information on the FIBI, search for "lake index of biological integrity" on the mndnr.gov website. Results from this survey indicate that the fish community in Big Spunk Lake is healthy as indicated by an FIBI score that exceeds the impairment threshold determined for similar lakes. These results are similar to the previous assessment which determined Big Spunk Lake was fully supported aquatic life use based on the FIBI. The recent survey results will be considered when the biological health of the lake is assessed during the Mississippi (Sartell) River Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency.

Big (Upper) Spunk Lake is a 440-acre lake located within a mile of the City of Avon in Stearns County. Big Spunk Lake has a maximum depth of 38 feet and an average summer water clarity of 10 feet. Oxygen levels were adequate for sport fish to a depth of 19 feet during the last week of June. Big Spunk Lake has a diverse aquatic plant community growing in dense beds around the lake out to a depth of 16 feet with Chara and coontail being the most common species. There is one public access on the northwest shore of the lake with parking available for six vehicle/trailer combinations as well as a dock and portable toilet. The Big Spunk Lake watershed is moderate in size and covers about 15,000 acres. Land use practices within the watershed consisted of 29% forest, 25% agriculture, 14% hay/pasture, 14% wetland, 11% open water,6% residential, and 1% grassland. Near shore Index of Biotic Integrity (IBI) sampling and emergent and floating leaf vegetation mapping were also completed to evaluate the physical habitat of Big Spunk Lake. Emergent and floating leaf vegetation covered approximately 73% of the shoreline with cattail and yellow waterlily being the most common. A standard summer survey was conducted in 2023 to monitor any changes in the fishery since the last survey conducted in 2016. The gill net catch of Northern Pike remained high and was above the normal range of expected values as well as above the long-term average for Big Spunk Lake. Pike ranged from 12 to 33 inches and averaged 21 inches and 1.6 pounds. Only 12% percent of Northern Pike sampled were longer than 26 inches. Anglers are encouraged to harvest the small pike (under 22 inches) and release the larger ones to help achieve a more balanced fish community and to improve growth rates. Lower pike numbers may also increase Walleye stocking success and allow Yellow Perch numbers (which are low) to increase. Higher perch populations are desirable as they are an important prey species for both Walleye and Northern Pike. Big Spunk Lake has been stocked with Walleye fingerlings every other year for several decades. The gill net catch of Walleye in 2023 was similar to the 2016 survey and was within the range of what we would expect to see for similar lakes. Walleye ranged in length from 15 to 28 inches and averaged 19 inches and 2.6 pounds. Growth was fast compared to statewide averages, taking four years to reach 18 inches. There is an excellent Largemouth Bass population with a wide range of sizes available to anglers including fish up to 21 inches. A total of 72 Largemouth Bass were sampled in 1.6 hours of electrofishing in June 2023. This was just below the average daytime catch rate for lakes in the Sauk Rapids Management Area. Of the catchable size Largemouth Bass (> 8 inches), 51% were longer than 12 inches and 14% were longer than 15 inches. Although not collected in this survey, Smallmouth Bass are also found in low numbers in Big Spunk Lake. The Bluegill trap net catch decreased in 2023 but remained within the range of expected values for lakes similar to Big Spunk. Bluegill only averaged five inches and fish over eight inches comprised only two percent of the sample. Anglers can expect to catch smaller Bluegill on Big Spunk with an occasional larger one mixed in. The Black Crappie catch also decreased from 2016 and fell below the long-term average for the lake. Fish ranged in length from four to ten inches with an average length of seven inches. Black Crappie catches are known to fluctuate widely depending on the success of spawning which is largely dependent on environmental factors. In 2023, 11 Tullibee were sampled in gill nets. While common in Middle Spunk Lake, this marks the first time since 1998 that Tullibee were sampled in Big Spunk, and the most ever sampled in a single survey. Other species sampled in low numbers during this survey included: Black Bullhead, Bowfin, Brown Bullhead, Green Sunfish, Hybrid Sunfish, Pumpkinseed, Rock Bass, Tullibee (Cisco), White Sucker, and Yellow Bullhead. Changes in shoreline development have the potential to negatively affect the health of a lake. It is important that all lake shore owners follow County shoreline rules and only mow a small area down to the lake to allow access and avoid clearing their entire shoreline. Native vegetation helps stabilize shoreline soils and acts as a buffer reducing the amount of pollution that enters a lake from runoff.

Based on Minnesota DNR survey data, anglers target Northern Pike, Walleye, Hybrid Sunfish, Largemouth Bass, and Bluegill in Big Spunk. See the full species list above for catch rates, size structure, and quality scores.

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

Big Spunk has a maximum depth of 38 feet and a mean depth of 15.9 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Big Spunk is from 2023.

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