May

A targeted survey of nearshore fish species in May Lake was conducted on July 25-27, 2022 by Index of Biological Integrity (IBI) Program Staff. Nearshore sampling sites were evenly spaced around the lake and each was sampled by backpack electrofishing and seining with a 50-foot seine, where possible. Backpack electrofishing was completed at all ten sampling stations. Similarly, a 50-foot seine was used to sample eight stations, and a 15-foot seine was used to sample two stations due to difficult site conditions including abundant lilies out to deep water along the shoreline. Nearshore sampling captured 15 species of fish including abundant numbers of seven species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, Mimic Shiner, Pugnose Shiner, and Rock Bass) and no species that are classified as tolerant of disturbance. A concurrent summer trap net survey was conducted by IBI Program Staff. Nine trap nets were set along the shoreline in locations that encompassed multiple habitat types. Bluegill and Rock Bass comprised a majority of the trap net catch by biomass, with Bluegill most abundant by number. The number of Bluegill sampled per net was just below the 50% quartile for similar Lake Class 31 lakes and the average length was 5.0 inches, with 14% over 7 inches. The nearshore and trap net data were combined with gill net data from a July 2020 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, Iowa Darter, and Rock Bass), while other species are tolerant of degraded conditions (e.g., Common Carp 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. Data from this survey indicates May Lake is healthy as indicated by an exceptionally high FIBI score, well above the impairment threshold for aquatic life use determined for similar lakes. Data from this survey will contribute biological information about the health of the fish community to the Leech Lake River Watershed assessment process in coordination with MN Pollution Control Agency.

A targeted survey of nearshore fish species in May Lake was conducted on July 22, 2021, by Index of Biological Integrity (IBI) Program staff. 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 all 10 sampling stations. Similarly, a 50-foot seine was used to sample eight stations and a 15-foot seine was used to sample two stations. Nearshore sampling captured 14 species of fish including five species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, and Rock Bass) and none that are tolerant of disturbance. The nearshore data were combined with trap net and gill net data from a July 2020 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, Iowa Darter, and Rock Bass), while other species are tolerant of degraded conditions (e.g., 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 May Lake is healthy as indicated by an FIBI score that exceeds the exceptional use threshold determined for similar lakes. These results will be considered when the biological health of the lake is assessed during the Leech Lake River Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency.

May Lake (DOW 11-0482, Lake Class 31) is a 143-acre lake on the south edge of the City of Walker, MN. May Lake has 2.26 miles of shoreline with a maximum depth of 59 feet. Littoral area is 74 acres. The lake is connected by a navigable channel to Long Lake, which has a US Forest Service public access. The DNR has classified Minnesota's lakes into 43 different classes based on physical, chemical and other characteristics. May Lake is in Lake Class 31; lakes in this class are generally clear, productive, and have moderate depth. Other area lakes in this class include Bowen, Five Point, Sanborn, Ponto, Welsh and Widow. May Lake is managed primarily for Northern Pike, Largemouth Bass, and Black Crappie and secondarily for Bluegill, Cisco, and Muskellunge. However, no Muskellunge have ever been sampled in May Lake, and the few reported by anglers could have been remnant migrants from Leech Lake prior to barrier construction that limited fish passage. Northern Pike numbers were below what has been seen in recent surveys in this lake with seven fish per net caught, below the management goal of 8 to 10 fish per gill net. In the 2020 survey Northern Pike ranged in length from 10 to 34 inches with an average length of 18 inches. Largemouth Bass catch rates tied for the second highest in this lake with fish ranging in length from 6 to 20 inches. Largemouth Bass averaged 11 inches. Long-range management goals are assessed using spring electrofishing, which was not conducted in 2020. Black Crappie were caught at a level comparable to recent surveys and met the management goals of at least one fish per trap net and one fish per gill net. Black Crappie ranged in length from 5 to 11 inches, with an average of eight inches. Bluegill abundance was lower than in recent surveys with nine fish per trap net caught. The 2020 Bluegill catch was lower than the long range management goal of 15-25 fish per trap net. Bluegill had an average length of five inches and fish up to eight inches were sampled. Tullibee (Cisco) were sampled at rates close to past surveys in this lake with just over one fish per gill net, meeting the management goal of 1-3 fish per net. The Tullibee (Cisco) lengths ranged from 11 to 15 inches. Tullibee (Cisco) can provide important forage for larger predator fish in addition to offering an angling opportunity. Walleye abundance has remained stable at low levels with less than one fish per gill net and only two fish sampled in this survey. Yellow Perch numbers were low compared to similar lakes, comparable to recent surveys in this lake. Other fish species that anglers can expect to encounter include, Brown Bullhead, Yellow Bullhead, Hybrid Sunfish, Pumpkinseed and Rock Bass. People can have significant impacts on lakes and the fish populations they support. Harvest, lakeshore development, removal of shoreline vegetation, and introductions of invasive species can all adversely affect fish populations. Currently, no aquatic invasive species (AIS) have been identified in Lake May. AIS are moved from infested to non-infested waters by anglers, boaters, and lake shore owners and can adversely impact lakes and fish populations. To avoid spreading AIS, lake users are required to remove all aquatic plants or animals from their watercraft and drain all water from their boat before leaving the access. If you suspect an infestation of an invasive species in this lake, save a specimen and report it to a local natural resource office. Additional information on all of these topics can be found on the DNR website (www.dnr.state.mn.us) or by contacting the Walker Area Fisheries office.

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

We don't have a confirmed public access point on record for May. Check the DNR LakeFinder page for current access details before you go.

May has a maximum depth of 59 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in May is from 2022.

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