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Background Nickel Lake is a 13.2 acre natural lake in northern Itasca County. The lake has a maximum depth of 36.5 feet and clear water with a Secchi disk transparency of 18 feet. Nickel Lake has very soft, infertile water, which limits fish production. Nickel Lake has no inlets or outlets. Temperature and dissolved oxygen measurements from several profiles have determined that suitable conditions exist for stream trout management. Nickel Lake has a long history of stream trout management and the presence of non-trout species in the lake has limited past success of the fishery. The lake was first stocked with Rainbow Trout in 1938, although natural populations of bass, sunfish, perch, and white suckers already existed. The lake was designated as a stream trout lake in 1955 and reclaimed with rotenone to remove the native fish species. Rainbow Trout fingerlings were stocked following the reclamation to establish a stream trout fishery. The 1972 and 1974 assessment nettings were the first netting efforts conducted after the 1955 reclamation. Both assessments captured other fish species including suckers and Largemouth Bass that compete with trout. The lake was reclaimed again in August 1982 using rotenone and Brook Trout were stocked the following spring. The lake remained relatively void of non-trout species for several years. The 2004 assessment resulted in a relatively high catch of Golden Shiners, which had probably been introduced via a bait bucket. Anglers reported catching bluegill in 2009 and Bluegill were caught in large numbers in the 2010 and 2015 assessments, indicating that a population had become established. Largemouth Bass were sampled in 2015. The lake was stocked annually with either Rainbow or Brook Trout, or both from 1955 to 1987. Rainbow Trout were stocked annually from 1988 to 2003. Yearling Brown Trout were stocked in the fall of 2004 to utilize the golden shiners as prey and hopefully reduce shiner abundance. Rainbow Trout and Brown Trout were stocked in alternate years from 2004-2009. Since 2010, only Brown Trout have been stocked annually. The lake management plan for Nickel Lake was revised in 2011. The long range goals of the plan were to maintain a put, grow, and take stream trout fishery capable of consistently providing anglers with stock sized rainbow and Brown Trout (10 inches) with sufficient growth and survival that 20% of the fish exceed 15 inches and occasionally some fish will attain and exceed 18 inches. Fall trap net catch rates should exceed 1.0 trout per net. Assessment Results Bluegills remained the most common fish in both the gill net and trap net samples. Bluegill ranged from 1.7 to 7.8 inches with an average length of 5.2 inches in 2015. Size quality was poor and similar to the previous assessment. Lakes with similar habitats produce slow growing sunfish and Bluegills are not expected to grow large in Nickel Lake. Several year classes were present and growth was near the lake class average as Bluegill averaged 6.0 inches by age 6. The presence of Bluegill is expected to greatly limit trout production in the future. Largemouth Bass were sampled for the first time since the previous reclamation in 2015, occurring in both the gill net and trap net sample. Bass were generally small, as length ranged from 3.2 to 13.6 inches and averaged 9.6 inches. Three year classes were present, suggesting that natural reproduction had occurred. Growth was near the statewide average with bass averaging 12.9 inches by age 5. Only six Brown Trout were captured at a rate of 1.0/gill net and 0.3/trap net, failing to meet the long range goal of the lake management plan. Brown Trout lengths varied from 9.8 to 18.3 inches. Length distribution suggests that the fish were from two stockings. Golden shiners were captured at a rate of 3.5/ gill net. A previous assessment in 2004 captured golden shiners at a rate of 18.8/trap net. It appears that the introduction of Brown Trout and Largemouth Bass may have negatively influenced golden shiner abundance. The catch rate goals of the lake management plan were not met. The introduction of Bluegill and Largemouth Bass has likely resulted in poor survival of stocked trout. Future management may include discontinuing trout management on Nickel Lake altogether, or conducting an expensive reclamation to remove the non-salmonid fish. Anglers should be reminded that it is unlawful to use live bait in designated trout waters and illegal to stock fish into public waters without a DNR permit. Illegal fish stockings, even when done with good intentions, often have unforeseen and detrimental consequences on the fish community and future angling success.

Nickel Lake is a 13.2 acre natural lake in northern Itasca County. The lake has a maximum depth of 36.5 feet and clear water with a Secchi disk transparency of 18 feet. Nickel Lake has very soft, infertile water, which limits fish production. Nickel Lake has no inlets or outlets. Temperature and dissolved oxygen measurements from several profiles have determined that suitable conditions exist for stream trout management. Nickel Lake has a long history of stream trout management and the presence of non-trout species in the lake has limited past success of the fishery. The lake was first stocked with rainbow trout in 1938, although natural populations of centrarchids, perch, and white suckers already existed. The lake was designated as a stream trout lake in 1955 and reclaimed with rotenone to remove the native fish species. Rainbow trout fingerlings were stocked following the reclamation to establish a stream trout fishery. The 1972 and 1974 assessment nettings were the first netting efforts conducted after the 1955 reclamation. Both assessments captured other fish species including suckers and largemouth bass that compete with trout. The lake was reclaimed again in August 1982 using rotenone and brook trout were stocked the following spring. The lake remained relatively void of non-trout species for several years. The 2004 assessment resulted in a relatively high catch of golden shiners, which had probably been introduced via a bait bucket. Anglers reported catching bluegill in 2009 and bluegill were caught in large numbers in the 2010 assessment, indicating that a population had become established. The lake was stocked annually with either rainbow or brook trout, or both from 1955 to 1987. Rainbow trout were stocked annually from 1988 to 2003. Brown trout are more piscivorous than other trout species. Yearling brown trout were therefore stocked in the fall of 2004 to utilize the golden shiners as prey and hopefully reduce shiner abundance. Rainbow trout and brown trout have been stocked in alternate years since 2004. The lake management plan for Nickel Lake was revised in 2005. The long range goals of the plan were to maintain a put, grow, and take stream trout fishery capable of consistently providing anglers with stock sized rainbow and brown trout (10 inches) with sufficient growth and survival that 20% of the fish exceed 15 inches and occasionally some fish will attain and exceed 18 inches. Fall trap net catch rates should exceed 1.0 trout per net. Assessment Results Bluegill were the most common fish in both the gill net and trap net samples. The catch was relatively high compared to similar lakes. Bluegill ranged from 3.8 to 7.6 inches with an average length of 5.7 inches. Age analysis identified 3 year classes. The 2007 year class made up 79% of the sample. It appears that adult bluegill were likely illegally stocked prior to 2006 and spawned successfully in 2006 and 2007. The population may continue to grow as the fish from the 2006 year class reach maturity and increase the spawning stock. Some young of the year bluegill were captured in trap nets and minnow traps indicating that at least some reproduction occurred in 2010. Growth was fast compared to similar lakes with individuals exceeding 6 inches in 4 years. Growth rates will likely decrease as the population increases. The presence of bluegill is expected to greatly limit trout production in the future. Rainbow trout were captured at a rate of 1.5/gill net and 0.1/ trap net. Rainbow trout were generally of quality size as lengths ranged from 16.3 to 17.7 inches and averaged 17.2 inches. Rainbow trout appeared to be from the 2009 yearling stocking. Brown trout were captured at a rate of 7.5/gill net and 0.6/trap net. Brown trout lengths varied from 8.8 to 21.7 inches and averaged 15 inches from the gill net and 19 inches from the trap net. Brown trout appeared to be from both the 2010 and 2008 stockings, although some of the larger fish may have been even older. Golden shiners were captured at a rate of 4.0/ trap net. The previous assessment in 2004 captured golden shiners at a rate of 18.8/trap net. It appears that the introduction of brown trout may have negatively influenced golden shiner abundance. Other species sampled included finescale dace and fathead minnows. The goals of the lake management plan were generally met, given the excellent size structure and abundance of both rainbow and brown trout. Good trout angling opportunities appear to currently exist, especially for large trout. The effect of the bluegill introduction is unclear, but it is expected to negatively impact future trout management on Nickel Lake. Future management may include shifting to strictly brown trout stocking, although brown trout are considered less catchable than rainbow trout, discontinuing trout management on Nickel Lake altogether, or conducting an expensive reclamation to remove the bluegill. Anglers should be reminded that it is unlawful to use live bait in designated trout waters and illegal to stock fish into public waters without a DNR permit. Illegal fish stockings, even when done with good intentions, often have unforeseen and detrimental consequences on the fish community and future angling success.

Temperature and dissolved oxygen measurements from various depths from the surface to the bottom of the deepest part of the lake, 30 feet, indicated that habitat was suitable for stream trout from the lake's surface down to 25 feet. This indicates that the entire littoral zone, the shoal water that extends out to 15 feet, which is the most productive portion of the lake, is available for seeking food and cover. The rainbow trout catch was low in both gill nets, (0.5 fish/net), and ? inch trap nets, (0.4 fish/net), and as indicated by their size, 12-15 inches in length, they were likely all from the most recent spring stocking of 650 yearling fish. Golden shiners were abundant in the ? inch trap nets as their catch rate was 19.8 per lift while finescale dace and fathead minnows were sampled at lower rates of 1.0 and 0.1 respectively. The abundance of these species may provide adequate prey for other more piscivorous stream trout species such as brown trout or splake.

Based on Minnesota DNR survey data, anglers target Brook Trout, Brown Trout, Rainbow Trout, Black Crappie, and Largemouth Bass in Unnamed . See the full species list above for catch rates, size structure, and quality scores.

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

Unnamed has a maximum depth of 36.5 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Unnamed is from 2015. Surveys this old should be treated with some caution — fish populations change over time.

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