Portage Lake (main bay)

How big is Portage Lake (main bay)?

How deep is Portage Lake (main bay)?

What kind of fish can you catch in Portage Lake (main bay)?

What are the closest cities to Portage Lake (main bay)?

Are there boat launches on Portage Lake (main bay)?

Are there places to eat and drink near Portage Lake (main bay)?

A targeted survey of nearshore fish species in Portage Lake was conducted on August 8-9, 2023, by Index of Biological Integrity (IBI) Program staff. Nine 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. Similarly, a 50-foot seine was used to sample six stations, a 15-foot seine was used at three stations, and site conditions prevented the use of seines at one station. Nearshore sampling captured fourteen species of fish including six species that are intolerant of disturbance (i.e., Banded Killifish, Blackchin Shiner, Blacknose Shiner, Iowa Darter, Mimic Shiner, and Smallmouth Bass) and zero that are tolerant of disturbance.

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 eight species of fish. Bluegill comprised a majority of the catch by number, whereas Largemouth Bass, Bluegill, and Yellow Bullhead comprised a majority by biomass.

The nearshore and trap net data were combined with gill net data from a July 2022 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 Portage Lake is healthy as indicated by an FIBI score that exceeds the general use threshold determined for similar lakes. These results will be considered when the biological health of the lake is assessed during the Redeye River Watershed assessment process, which will be completed in coordination with MN Pollution Control Agency.

In addition to the fish survey, Minnesota DNR Fisheries IBI program staff conducted an assessment of lakeshore habitat on Portage Lake on Sep 22 2023, following the Score the Shore survey protocols. The assessment consisted of 28 survey sites evenly spaced 150 meters around the lake. Assessments were made in three habitat zones: Shoreline Zone (the shore-water interface to the top of the natural bank), Shoreland Zone (land-ward from shoreline to development structure or 100 feet), and Aquatic Zone (lake-ward 50 feet of shoreline). The average lakewide habitat score was 75.4 (+/- 4.3) out of 100 possible. A score of 75.4 indicates the lakewide shoreline condition is Moderate, but a large difference was noted in shoreline condition between undeveloped and developed sites. Undeveloped sites had a mean score of 94.4, and excellent shoreline condition. However, developed sites were in poor condition with a mean score of 58.9.

What is the average air temp for Portage Lake (main bay)?

Are there any state parks near Portage Lake (main bay)?