Ruby

Ruby Lake is located seven miles southeast of Marcell, MN in the Big Fork River watershed and the Chippewa National Forest. Ruby is a deep, clear lake with steep drop-offs and a limited amount of aquatic vegetation. The 2009 lake management plan lists Walleye as the primary management species with Northern Pike and Smallmouth Bass as secondary management species. Ruby Lake has generally been known as a lake that produces lower numbers of Walleye, with the opportunity to catch bigger fish (>25 inches). Recent management included stocking Walleye fingerlings in odd numbered years at one pound/littoral acre. A targeted survey (gill nets only) was conducted in early July 2017 to evaluate the success of the stocking and collect updated information on the fishery. Walleye were sampled in numbers similar to past surveys and within the typical range for similar lakes. Size structure declined from past surveys. Walleye ranged from 9.4 to 22.2 inches with an average length of 15.2 inches. Ages 2, 4-6 and 9 were represented with age 2 fish making up 58% of the age distribution. Six of the previous ten years were stocked year classes, and 95% of the sample corresponded to stocked years. Growth was average with Walleye attaining 17.3 inches at age 5. Northern Pike numbers declined slightly from previous surveys but were within the typical range for similar lakes. Size structure was modest; pike ranged from 15.4 to 29.3 inches with an average length of 21.8 inches. Ages 2-5 and 7 were represented with ages 2 and 4 the most frequently sampled. Growth was average with pike attaining 21.5 inches at age 4. The Yellow Perch catch rate was similar to other recent surveys within the typical range for lakes like Ruby. Perch ranged from 5.7 to 8.5 inches. Other species sampled included Bluegill, Largemouth Bass, Smallmouth Bass, Pumpkinseed, Rock Bass and White Sucker. Anglers can help maintain or improve the quality of fishing by practicing selective harvest. Selective harvest allows for the harvest of smaller fish for table fare, but encourages release of medium to large sized fish. Releasing these fish can help maintain balance in the fish community in Ruby Lake and provide anglers the opportunity to catch more and larger fish in the future. Lakeshore owners may affect fish populations not only through harvesting fish, but also through land use practices. Good water quality and fish populations are the direct result of good land use practices. Shoreline habitat consists of aquatic plants, woody plants and natural lake bottom soils. Plants in the water and at the water's edge provide habitat, prevent erosion and absorb excess nutrients. Shrubs, trees, and woody debris such as fallen trees or limbs provide good habitat both above and below the water surface and should be left in place.

Ruby Lake is a 243 acre lake located 7 miles southeast of Marcell, MN in the Big Fork River watershed and the Chippewa National Forest. Ruby Lake has been part of a statewide study evaluating different walleye stocking strategies including fry, fryling and three densities of fingerlings. All stocked fish were marked with oxytetracycline (OTC) to determine the relative contribution of stocked fish from natural reproduction. Since the most recent assessment was part of the stocking evaluation, gill nets were the only gear used and age and growth data were only collected from walleye. Ruby Lake was stocked with approximately 92,000 marked walleye fry in 2001, and 106,000 marked fry in 2003. In addition, 117 lbs of marked fingerlings (1,229 fish) were stocked in 2005. Night electrofishing assessments for young of the year or yearling walleye were conducted annually from 2001 through 2006 to evaluate these stockings. These assessments sampled very few fish. The 2008 walleye gill-net catch rate was below the lake class median at 2.0/net. Of the 12 fish sampled, four were aged to an OTC marked stocking year (2005), and all four were confirmed to have OTC marks. Previous gill-net assessments in 2004 and 2006 sampled very few marked fish from the 2001 and 2003 fry stockings. Overall, the results of the various assessments on Ruby Lake have indicated the fry stockings were generally unsuccessful, while fingerlings have performed somewhat better. Some natural reproduction has been documented in all recent assessments. Walleye growth in 2008 was above the statewide average for ages 1-4, and similar to the statewide average for all other ages. The northern pike gill-net catch rate was 9.3/net; above the lake class normal range but similar to previous assessments. Size structure was moderate; sampled pike ranged from 14.8 to 32.7 inches, with a mean length of 22.6 inches and a mean weight of 2.7 pounds. The gill-net catch rate for largemouth bass equaled the lake class first quartile (0.5/net), while the catch rate for smallmouth bass approached the lake class third quartile at 1.3/net. Gill-net catches for both species have typically been low, although catch rates for smallmouth bass have exceeded the lake class median in the last two assessments. The yellow perch gill-net catch rate was within the lake class normal range at 2.8/net, similar to recent assessments. The gill-net catch rate for tullibee was below the lake class normal range at 0.5/net. Catch rates in previous assessments have varied from 0.2 to 6.5/net. Other species sampled included black crappie, bluegill, pumpkinseed sunfish, rock bass and white sucker.

Walleye were sampled with gill nets at a rate within the lake class expected range, but it was the second lowest catch rate since 1967. The fish sampled were a good size, averaging 4.1 pounds, but it appears that there was limited recruitment and no fish were sampled below 17.3 inches. The average length was 22.2 inches and the longest was 27.6 inches. Ruby has been part of a statewide research project evaluating different stocking strategies. As part of this project, Ruby has been stocked with oxytetracycline (OTC) marked fry in 2001 and 2003, and OTC marked fingerlings in 2005. Only two fish were sampled that were aged to an OTC marked stocking year (2001). One fish was marked representing a stocked fish and the other was not (natural reproduction). Northern pike were sampled at a rate within the lake class expected range, similar to the 2001 assessment but below the highest rate in the 2004 special assessment. The longest northern pike sampled was 33.5 inches, and the average length was 23.4 inches. The size structure was good with 17% of the fish sampled over 29 inches. The growth rate was above the state average for ages one, two and five, and similar to the state average for the rest. Largemouth bass were sampled in gill nets at an expected rate for the lake class, while smallmouth bass, sampled in gill nets, were above the lake class expected range. Both species were also sampled with electrofishing at a moderate rate, but because of changes in the survey stations no real relationship to the previous assessment can be made. The electrofishing stations used for the bass population assessment were run concurrent with the six stations used for the walleye research project. The size structure appears to be moderate and growth rates were below or near the state average for both species. Bluegill were sampled in trap nets at a rate above the expected lake class range, similar to the previous assessment. Historically, the abundance has been lower. The size structure was poor with an average length of 5.2 inches and no fish sampled over eight inches. Yellow perch were sampled within the lake class expected range, and slightly lower than the previous assessment. Only one tullibee was sampled in 2006, the lowest recorded catch rate. Both species have had fluctuating populations and have been historically sampled at lower densities. Other species sampled include black crappie, pumpkinseed, rock bass, and white sucker.

Based on Minnesota DNR survey data, anglers target Walleye, Smallmouth Bass, Northern Pike, Bluegill, and Rock Bass in Ruby. See the full species list above for catch rates, size structure, and quality scores.

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

Ruby has a maximum depth of 88 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Ruby is from 2017. Surveys this old should be treated with some caution — fish populations change over time.

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