O'Leary

O'Leary Lake is a 202 acre class 5 lake located in Voyageurs National Park. This interior park lake is located approximately 10 miles north-northwest of the community of Crane Lake, Minnesota. O'Leary is accessed via a portage trail from Hammer Bay in the east end of Namakan Lake, and no boats are allowed to be carried in due to invasive species concerns. O'Leary is a clear lake with a maximum depth reported to be 52 feet. Due to its remote location, the fish populations of O'Leary appear to be exposed to very little angling pressure. A standard fisheries survey was completed in late August of 2016. Largemouth Bass were sampled in O'Leary for the first time during a fisheries survey. Bass are not easily caught with traditional nets used for sampling so they were caught in low numbers, however it was noted that there were many of these fish observed during the survey. Northern Pike are abundant in O'Leary. Even though they appear to be densely populated, growth and average size are still in the expected range. Pike had an average size of 2.5 pounds during the 2016 survey. Smallmouth Bass appear to be present in good numbers, and they are larger than expected for this type of lake. Smallmouth had an average size of 1.5 pounds and fish over 19 inches were caught in 2016. These fish also have very fast growth in comparison to other lakes in the International Falls Management Area. Walleye catch rates are within the expected range for this type of lake, and average size is excellent. The average length of Walleye caught in 2016 was over 19 inches, and these fish also had much faster growth rates than the average International Falls Management Area lakes. Yellow Perch were caught in low numbers in 2016. These fish exhibited small average sizes and slower than average growth. Other fish caught in low numbers during the survey included Bluegill, Pumpkinseed Sunfish, and White Sucker.

O'Leary is a 197 acre lake located approximately 10 miles north of Crane Lake. The lake is in Voyageurs National Park and access is limited to a portage from Namakan Lake. Several predator species were present in 2001 and most have shown increases in abundance with each investigation. Conversely, prey abundances have declined dramatically for each species and predators in the small length catagories are rare. Northern pike abundance in gill nets was 10.50 fish/set, which was over three times higher than most lakes of this type. Six year-classes were present in the gill nets and age ranged from 2-9 years. Total length (TL) ranged from 9.9-29.3 inches for fish captured in gill and trap nets. Mean TL at age-4 for northern pike captured in gill nets was below the area mean, but slightly above the statewide mean. The mean weight was below most lakes of this type. Smallmouth bass gill-net abundance has increased from 0.33 fish/set in 1972 to 1.67 fish/set in 2001, which was greater than most lakes of this type. Mean weight for smallmouth bass sampled in gill nets was also greater than most lakes of this type. Growth was excellent; mean TL at age-4 was much greater than other lakes in the International Falls Management Area. Walleye gill-net abundance has increased dramatically from the previous investigation in 1979 when they were first captured in O'Leary Lake. However, the gill-net catch rate of 2.83 fish/set in 2001 remained well below most lakes of this type. Five year-classes were present in the gill nets and age ranged from 5-9 years. Total length ranged from 19.9-24.1 inches and the average was 20.4. Growth was excellent; mean TL at age-4 was much greater than the area and statewide averages. Declines in forage species were evident in 2001. Yellow perch gill-net abundance has declined dramatically from 35.83 fish/set in the 1972 investigation to 0.50 fish/set in 2001. Likewise, gill-net abundance of white suckers declined from 16.33 fish/set in 1972 to 0.33 fish/set in 2001. Additionaly, brown bullheads were not caught in 2001, but were abundant in 1979.

Based on Minnesota DNR survey data, anglers target Northern Pike, Walleye, Smallmouth Bass, Largemouth Bass, and Pumpkinseed in O'Leary. 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 O'Leary. Check the DNR LakeFinder page for current access details before you go.

O'Leary has a maximum depth of 52 feet and a mean depth of 25 feet, per Minnesota DNR data.

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

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