John

A targeted survey of nearshore fish species in John Lake, was conducted on July 31st, 2025, by Area Fisheries 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 10 sampling stations. Similarly, a 50-foot seine was used to sample 4 stations, and a 15-foot seine was used at 1 station. Five stations were not seined due to deep water and dense lilies. Nearshore sampling captured 14 species of fish including 2 species that are intolerant of disturbance (i.e., Banded Killifish and Iowa Darter) and 1 that is tolerant of disturbance (i.e., Green Sunfish). The nearshore data were combined with trap net and gill net data from a July 2016 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., Banded Killifish and Iowa Darter), 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 provide evidence that the fish community in John Lake is healthy as indicated by an FIBI score above the general use impairment threshold for aquatic life use determined for similar lakes. These results are similar to previous findings which indicated that John Lake is fully supporting aquatic life. The survey results will be considered when the biological health of the lake is assessed during the North Fork Crow River watershed assessment process, which will be completed in coordination with MN Pollution Control Agency. You can help protect the fish community in John Lake by reducing runoff, maintaining natural shorelines, and preventing the spread of invasive species.

A targeted survey of the nearshore fish community was conducted on August 22, 2016 by Fisheries Lake IBI program staff. Sampling stations 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 stations with four sites sampled from the boat. A 50-foot seine was used to sample two stations, a 15-foot seine was used at four stations, and conditions prevented the use of seines at four sampling sites. Nearshore sampling captured 17 native species of fish including several species that are intolerant of disturbance (Banded Killifish, Blackchin Shiner, Blacknose Shiner, and Iowa Darter) and a single species that is tolerant of disturbance (Green Sunfish). Data from this survey is combined with data from a standard game fish survey completed in July 2016 to calculate a Fish-based Index of Biologic Integrity (FIBI) that describes the overall health of the lake. The FIBI score for John Lake based on this survey is above the impairment threshold for aquatic life use determined for similar lakes and indicates a healthy fish community. Data from this survey will be included as part of a process to assess the condition of surface waters of the North Fork Crow River watershed.

A targeted survey of the nearshore fish community was conducted on August 22, 2016 by Fisheries Lake IBI program staff. Sampling stations 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 stations with four sites sampled from the boat. A 50-foot seine was used to sample two stations, a 15-foot seine was used at four stations, and conditions prevented the use of seines at four sampling sites. Nearshore sampling captured 17 native species of fish including several species that are intolerant of disturbance (Banded Killifish, Blackchin Shiner, Blacknose Shiner, and Iowa Darter) and a single species that is tolerant of disturbance (Green Sunfish). Data from this survey is combined with data from a standard game fish survey completed in July 2016 to calculate a Fish-based Index of Biologic Integrity (FIBI) that describes the overall health of the lake. The FIBI score for John Lake based on this survey is above the impairment threshold for aquatic life use determined for similar lakes and indicates a healthy fish community. Data from this survey will be included as part of a process to assess the condition of surface waters of the North Fork Crow River watershed.

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

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

John has a maximum depth of 28 feet and a mean depth of 12.9 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in John is from 2016. Surveys this old should be treated with some caution — fish populations change over time.

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