Pine Mountain

Pine Mountain is a designated stream trout lake, managed for a variety of trout species since at least 1934. The current (2010) lake management plan continued a stocking regime for Splake that called for 6,000 fingerlings to be stocked annually. The long range goal for Splake in this lake is a minimum trap net catch of 4.8 fish/net, with some fish over 16 inches present. This was to have been the third of three surveys scheduled in the 2010 LMP to evaluate Splake stocking, monitor summer water quality, and monitor the lake for introductions of undesirable fish species. The first (in 2011) was canceled due to a lack of staff and funding, but the second was completed as planned in 2016. Splake were apparently abundant in 2021. Most of the fish collected were 12 to 16 inches in length, with a few larger fish (up to 19 inches in length) present. The 2021 Splake trap net catch easily exceeded the goal from the 2010 LMP, and the size goal in that plan was met by the capture of several fish over 16 inches in length. At 8.10 fish/net, the catch was well above the normal range (0.6-3.2 fish/net) for Splake catches in fall surveys of stream trout lakes in this area. The 2021 catch was the highest trout catch (Splake or Brook Trout) seen in this lake since at least 1993. The mean weight for Splake taken in trap nets was at the upper end of the normal range (0.58-1.18 lb/fish) for fall catches in this area. Four stocked year classes contributed to the 2021 catch, with fish from the 2016 and 2018 year classes accounting for about 90% of the total catch. Splake as old as age-6 were sampled, indicating excellent long term survival in this lake. Splake growth had been slow; fish reached a mean length of just 10.9 inches at the end of their third year, compared to an area average of 12.6 inches. Slow growth may have been due to high competition between Splake (large numbers of Splake present), competition from relatively high numbers of White Sucker also found in this survey, and high seasonal water temperatures.. Temperature-oxygen measurements made in late August as part of this survey suggest stress caused by high surface water temperatures could have contributed to slow growth of Splake. Splake are believed to have habitat requirements similar to those for Brook Trout. Optimal conditions for Brook Trout are water temperatures of 68 F or less, with at least 5.0 ppm dissolved oxygen. Water temperatures over 68 F are stressful, and prolonged exposure to those higher temperatures can result in slower growth, particularly among larger fish. Measurements in Pine Mountain Lake on August 26 2021 found optimal conditions for Splake were limited to a very narrow band at a depth of about 15 ft. Deep waters that might have provided cool enough water lacked sufficient dissolved oxygen, while shallower waters were slightly too warm (on that date). Data collected at other Grand Marais sites in 2021 suggested surface water temperatures may already have been cooling for the fall by the date of this profile, so conditions may have been more stressful earlier in the summer. No new (to this lake) undesirable fish species were collected in this survey. White Sucker gill and trap net catches were within normal ranges for stream trout lakes in this area, and were typical for this lake. White Sucker compete with trout for invertebrate forage, but a fair proportion of those collected in 2021 were small enough to have been preyed on themselves by the larger Splake in this lake. We don't know the extent to which Splake would prey on White Sucker, even when suitable sizes are available.

Pine Mountain is a designated stream trout lake, and has been managed for trout since at least 1934. The current (2010) lake management plan continued a stocking regime for Splake that called for 6,000 fingerlings to be stocked annually. The long range goal for Splake in this lake is a minimum trap net catch of 4.8 fish/net (a relatively high number of fish), with some fish over 16 inches present. This was to have been the second of three surveys scheduled in the 2010 LMP to evaluate Splake stocking, monitor summer water quality, and monitor the lake for introductions of undesirable fish species. The first (in 2011) was canceled due to a lack of staff and funding, making this the first full standard survey completed on this lake since Splake stocking began in 2002. Splake were abundant in Pine Mountain Lake in 2016, and although few large fish were present, many fish in the 12-15-in length range were available. The 2016 Splake trap net catch exceeded the goal from the 2010 LMP, and the size goal in that plan was met by the capture of one 17-inch fish. At 6.50 fish/net, the catch exceeded the top of the normal range (3.25 fish/net) for Splake catches in fall surveys of stream trout lakes in this area. The average weight of Splake taken in trap nets was close to average (0.74 lb/fish) for fall catches in this area. Six stocked year classes contributed to the 2016 catch, with fish from the 2012 and 2013 year classes accounting for 83% of the total catch. Low numbers of one- and two-year-old fish taken in this survey may have been due to predation from relatively high numbers of larger Splake present from earlier stockings. Splake growth had been slow; fish reached a mean length of just 10.1 inches at the end of their third year, compared to an area average of 12.8 inches. Slow growth may have been due to heavy competition with other Splake (high numbers of Splake present), and competition from relatively high numbers of White Sucker. Temperature-oxygen measurements made in late August as part of this survey suggest slow growth of Splake could also be related to stress caused by reduced thermal habitat. Splake are believed to have habitat requirements similar to those for Brook Trout. Optimal conditions for Brook Trout are water temperatures of 68 F or less, with at least 5.0 ppm dissolved oxygen. Water temperatures over 68 F are stressful, and prolonged exposure to those higher temperatures can result in slower growth, particularly among larger fish. Exposure to water temperatures over 77 F can be lethal. Measurements in Pine Mountain Lake on August 25 2016 found optimal conditions for Splake, if any existed, were limited to a very narrow band at a depth of about 16 ft. Deep waters that might have provided cool enough water lacked sufficient dissolved oxygen, while shallower waters were too warm. While not lethal, warm surface waters observed in 2016 could have resulted in stress responses, including slower growth, among Splake. No new (to this lake) undesirable fish species were collected in this survey. White Sucker gill and trap net catches were above normal for the lake class, and for stream trout lakes in this area, but were typical for this lake. Most suckers were too large to have provided forage for any but the largest trout, and all would have competed with trout for invertebrate forage.

Brook trout abundance was typical for this lake, and mean weight had increased slightly compared to recent assessments. Both measures were above the median for area stream trout lakes. Lengths caught ranged from 7.8 inches to 18.3 inches. Ages 1 through 4 were collected. This was as expected, because brook trout of most stocked strains die of natural causes before age 5. Growth rates had been about average for age-1 brook trout, and slightly below average for ages 2 and 3. On average, brook trout in Pine Mountain Lake reached 8.5 inches by age 2 and 12.2 inches by age 3, compared to averages for area lakes of the same class of 9.8 inches and 13.1 inches, respectively.Stocking of brook trout in Pine Mountain Lake has been discontinued. Splake fingerlings were stocked in fall 2002, and will be stocked each fall in the near future.

Based on Minnesota DNR survey data, anglers target Brook Trout, Splake, and Rainbow Trout in Pine Mountain. See the full species list above for catch rates, size structure, and quality scores.

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

Pine Mountain has a maximum depth of 30 feet and a mean depth of 11.6 feet, per Minnesota DNR data.

The most recent Minnesota DNR survey data for the main sport fish in Pine Mountain is from 2021.

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