Louisa

A targeted survey of nearshore fish species in Louisa Lake was conducted beginning on July 20th, 2020 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 10 sampling stations, but three stations were sampled from the boat due to site conditions. Similarly, a 50-foot seine was used to sample six stations, and site conditions prevented the use of seines at four stations. Nearshore sampling captured 16 species of fish including one species that is intolerant of disturbance (Banded Killifish and Iowa Darter) and two that are tolerant of disturbance (Common Carp and Green Sunfish). A concurrent summer trap net survey was conducted July 20th-22nd, 2020 by IBI Program Staff. Nine trap nets were set along the shoreline and in shallow offshore locations that encompassed multiple habitat types. Bluegill and Black Crappie comprised a majority of the trap net catch by number, and White Sucker and Northern Pike comprised a majority of the catch by biomass. The number of Bluegill and Black Crappie sampled per net was above the between the 25th and 50th quartile for similar Lake Class 24 lakes. The number of Common Carp sampled per net was below the 25% quartile for Lake Class 24 lakes. The mean weight of White Suckers caught were all above the 75% quartile for Lake Class 24 lakes. The nearshore and trap net data were combined with gill net data from a June 2019 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, Iowa Darters, Mimic Shiners), while other species are tolerant of degraded conditions (e.g. Green Sunfish, Fathead Minnows, and Common Carp). 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 provides evidence that the fish community in Louisa Lake is adversely impacted by stressors as indicated by an FIBI score below 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 Mississippi River - St. Cloud Watershed assessment process in coordination with MN Pollution Control Agency.

A targeted survey of nearshore fish species in Louisa Lake was conducted beginning on July 20th, 2020 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 10 sampling stations, but three stations were sampled from the boat due to site conditions. Similarly, a 50-foot seine was used to sample six stations, and site conditions prevented the use of seines at four stations. Nearshore sampling captured 16 species of fish including one species that is intolerant of disturbance (Banded Killifish and Iowa Darter) and two that are tolerant of disturbance (Common Carp and Green Sunfish). A concurrent summer trap net survey was conducted July 20th-22nd, 2020 by IBI Program Staff. Nine trap nets were set along the shoreline and in shallow offshore locations that encompassed multiple habitat types. Bluegill and Black Crappie comprised a majority of the trap net catch by number, and White Sucker and Northern Pike comprised a majority of the catch by biomass. The number of Bluegill and Black Crappie sampled per net was above the between the 25th and 50th quartile for similar Lake Class 24 lakes. The number of Common Carp sampled per net was below the 25% quartile for Lake Class 24 lakes. The mean weight of White Suckers caught were all above the 75% quartile for Lake Class 24 lakes. The nearshore and trap net data were combined with gill net data from a June 2019 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, Iowa Darters, Mimic Shiners), while other species are tolerant of degraded conditions (e.g. Green Sunfish, Fathead Minnows, and Common Carp). 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 provides evidence that the fish community in Louisa Lake is adversely impacted by stressors as indicated by an FIBI score below 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 Mississippi River - St. Cloud Watershed assessment process in coordination with MN Pollution Control Agency.

A survey of near shore fish species was conducted on Louisa Lake on July 8 - 12, 2019 by Sauk Rapids Area staff. Ten sampling sites were evenly spaced around the shoreline and each site was sampled by backpack electrofishing and seining. Near shore sampling captured 15 species of fish, including one species that is intolerant of poor water quality or habitat disturbance (Iowa Darter). The near shore fish survey data were combined with gill net and trap net data from a June 2019 standard survey to describe the fish community and provide a fish based Index of Biotic Integrity (FIBI) score based on expectations for similar lakes. A FIBI uses fish community data as a measurement of lake health. The FIBI score for Louisa Lake was 47, which was above the impairment threshold (FIBI > 45) using Tool 2. This survey is contributing to a watershed assessment process in coordination with the MN Pollution Control Agency. Louisa Lake is located in the Mississippi River - St. Cloud Watershed.

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

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

Louisa has a maximum depth of 44 feet and a mean depth of 10.5 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Louisa is from 2020.

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