5.7 SMALL LAKESwhitefishlake.org/wp-content/uploads/2020/06/NMLN_2018_Small-Lakes.pdfYellow water lily can be identified by itsheart shapedleaves. Most of the leaves are emergent,

Northwest Montana Lakes Volunteer Monitoring Network 2018 Program Summary

15 Whitefish Lake Institute

5.7 SMALL LAKES

(Surface Area <100 Acres)

AbbotBailey

Big TherriaultBootjack

Dollar Fish

HalfmoonHanson-Doyle

JetteLoon

Lost Coon McGilvray

Murray PetersonSkyles

Spencer Tetrault

Upper Whitefish



Abbot LakeTrophic Status: Oligo-mesotrophicSurface Area: 41 acresMaximum Depth: 20 feet (6.1 meters)

Abbot Lake is situated on glacial till and alluvium on the valley floor (Ellis & Craft, 2008).

The Lake is located four miles north of Bigfork, Montana in Flathead County at an elevation of 914 meters. This man-made lake is surrounded by private land ownership. Fish distribution records indicate a presence of largemouth bass, northern pike, pumpkinseed, and yellow perch. There is no public access to Abbot Lake.

Since 2011, high water has connected Abbot Lake to Echo Lake and Peterson Lake. Volunteers reported increased recreational boat use in 2011, 2012 and 2013 which may have been a result of the “no wake” restriction on Echo. Lakeshore home owners have reported increased erosion since 2011 due to increased recreational use from boats that have ballast tanks. In 2014, photographs were taken documenting shoreline erosion.

All oxygen and temperature depth profiles taken in late summer show Abbot Lake as evenly mixed during summer and fall samplings. Temperature profiles show that Abbot Lake has been within the avoidance threshold range for salmonids during all summer sampling dates, and it is considered a warm water fishery.

Abbot Lake’s 2010, 2011, and 2016 average calcium concentration was 30.4mg/L classifying it as a high risk for zebra mussel colonization. 2012 alkalinity level was reported at 140mg/L.



Location: 48.11772 N, 114.05183 W



Bailey LakeTrophic Status: OligotrophicSurface Area: 16 acresMaximum Depth: 30 feet (9.1 meters)

The geologic formations of the watershed that encompass Bailey Lake are dominated by glacial till (55%) with the remaining drainage area split evenly between Grinnel argillite and the Piegan group belt series (Ellis & Craft, 2008).

Bailey Lake is located seven miles north of Columbia Falls in Flathead County in the Glacier View Ranger District at an elevation of 1036 meters. Surrounding land ownership is primarily private.

Fish distribution records indicate a presence of brook trout, largemouth bass, longnose sucker, pumpkinseed, westslope cutthroat trout and yellow perch. Bailey Lake has a primitive, non-motorized, public access site requiring a short walk to the lake on the east shore.

Summer temperature and oxygen profiles show that Bailey Lake has been weakly stratified at thetime of summer sampling. Temperature profiles indicate the lake has been within the avoidance threshold range for salmonids at depths of up to 7 meters during July and August. Fall Hydrolab profiles show that the lake was evenly mixed during all sampling dates. In 2015, the fall temperature profile was warmest of all data collected.

Bailey Lake’s 2010, 2011, and 2016 average calcium concentration was 24.2mg/L classifying it as a moderate risk for zebra mussel colonization. 2012 alkalinity level was reported at 140mg/L. In 2015, Bailey Lake ranked second highest among small lakes for chlorophyll (a).

Bailey Lake Volunteer, Susie Bouton, records Secchi Depth. Photo courtesy WLI



Location: 48. 471192 N, 114.132242 W



Big Therriault LakeTrophic Status: OligotrophicSurface Area: 56 acresMaximum Depth: 70 feet (21.3 meters)

Big Therriault Lake is located in Lincoln County in the Kootenai National Forest of the Fortine Ranger District at an elevation of 1,690 meters. Surrounding land ownership is 100% U.S. Forest Service (USFS). Fish stocking and population survey records indicate a presence of westslope cutthroat trout. There is one motorized public access site located within the campground on Big Therriault Lake.

Temperature and oxygen profiles show that Big Therriault Lake was stratified or weakly stratified during summer sampling dates.

Total phosphorus, total nitrogen, and chlorophyll (a) were not detected above the lower reporting limit during many of the sampling events. Big Therriault Lake’s 2011/2106 average calcium concentration was 23mg/L classifying it as a moderate risk for zebra mussel colonization. The 2012alkalinity level was reported at 82mg/L. Big Therriault is one of the most oligotrophic lakes in the program. In 2015, fires prevented access to the lake.

The primitive boat launch at Big Therriault. Photo courtesy WLI.



Location: 48.931555 N, 114.875952 W



Volunteer Kim Corrette prepares for field sampling on Bootjack Lake. Photo courtesy WLI.

Bootjack LakeTrophic Status: Oligo-mesotrophicSurface Area: 35.4 acresMaximum Depth: 52 feet (15.8 meters)

Bootjack Lake is located in Flathead County ten miles west of Whitefish, at an elevation of 975 meters. Fish stocking records indicate a presence of cutthroat trout, rainbow trout, and westslope cutthroat trout. The only native fish recorded is the redside shiner. There is one primitive non-motorized public access site that requires a short walk to the lake. Access to the lake is open from April 1st - November 30th.

Temperature and oxygen profiles show that Bootjack Lake was stratified during all summer sampling dates. Temperature profiles indicate the lake has been within the avoidance threshold range for salmonids at depths of up to 5 meters during July and August. Oxygen profiles suggest that Bootjack Lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 10 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 5-9 meters.

When anoxic conditions occur at the benthic interface an oxidation reduction potential exists andnutrients stored in the sediment can be liberated back into the water column given the right conditions.

Bootjack Lake often ranks among the highest of small lakes for chlorophyll (a).

Bootjack Lake was surveyed for EWM 2011-2014 because of its relatively close proximity to Beaver Lake. Large plots of northern milfoil were found in the littoral zone; however, no EWM was discovered. The lake’s 2106 average calcium concentration was 34.3mg/L classifying it as a high risk for zebra mussel colonization.



Location: 48.42409 N, 114.49809 W



Dollar LakeTrophic Status: Oligo-mesotrophicSurface Area: 8.4 acresMaximum Depth: 48 feet (14.6 meters)

Dollar Lake is located in Flathead County west of Whitefish Lake at an elevation of 1,036 meters.Surrounding land ownership is 100% State Trust Lands. In October 2007, the lake was chemically treated to eliminate fathead minnows and redside shiners using liquid rotenone. Dollar Lake is a closed basin lake depending entirely on stocking for maintaining a trout population. Fish stocking records indicate a presence of rainbow trout and westslope cutthroat trout. There is one primitive non-motorized public access site on Dollar Lake.

Temperature and oxygen profiles show that Dollar Lake was stratified during all of the summer sampling dates. Temperature profiles indicate that the lake has been within the avoidance threshold range for salmonids at depths of up to 5 meters during July and August. Summer oxygen profiles indicate that Dollar Lake has been anoxic when stratified at depths greater than 8 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 5-8meters. Fall Hydrolab profiles show that the lake was evenly mixed or very weakly stratified during all sampling dates.

Dollar Lake often ranks among the highest of small lakes for total phosphorus, total nitrogen, and chlorophyll (a). Dollar Lake’s 2011/2016 average calcium concentration was 37.75mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 140mg/L.

A visual survey for EWM was conducted in 2011, 2012, and 2013 at the public access for Dollar Lake because it is located 4.5 miles from Beaver Lake in which EWM was discovered in 2012. No EWM was found, however, additional monitoring is recommended based on its proximity to Beaver Lake and the high amount of fishing pressure it receives. Additionally, a macrophyte survey was conducted in 2014. Results from that survey are described below.

Volunteer Penny Lestiko POV shot paddling out to monitor Dollar Lake. Photo courtesy Penny Lestiko.



Location: 48.446286 N, 114.41426 W



A macrophyte survey was conducted on Dollar Lake on September 4, 2014. A total of 46 sites were surveyed for aquatic plants, shoreline plants, and substrate. Plants that were commonly observed but were not dominant include flat stem pondweed, and Richardson’s pondweed.

Shoreline plants in order of dominance:1) Bulrush, 2) Cattail, 3) Carex, 4) Equisetum

Substrate composition for all sites was predominately gyttja, followed by gravel, boulder and cobble. The discovery of northern milfoil in Dollar Lake and its close proximity to Beaver Lake (where Eurasian watermilfoil was found in 2012) makes it a high risk for Eurasian watermilfoil (EWM) infestation.

Dollar Lake

Dominant Plant Distribution September 2014

Yellow Water Lily

Co-dominance

Chara

No Plants Present

Common Water Moss Naiad

49%

17%

15%

11%

6% 2%

Co-dominant Plant Species Composition

Percentage of Co-dominant Slice

Chara / American Pondweed 37.5Chara / Yellow Water Lily 37.5Chara / Naiad 12.5Yellow Water Lily / Naiad / Northern Milfoil / Variable Leaf Pondweed 12.5

Bullrush, equisetum and American pondweed. Photo courtesy WLI.



Naiad (right) is an aquatic plant that grows rooted in the substrate however fragments that have detached from the plant can survive freely. Populations can become locally dominant, as seen in this photo, and can form dense submerged mats of vegetation. The seeds from this plant provide an important food source for shorebirds and waterfowl. Although Naiad was the least dominant plant in Dollar Lake, it was observed growing in extremely dense patches along the south end of the lake.

Yellow water lily (left) and American pondweed are often found growing together on many of the Program lakes. Yellow water lily can be identified by its heart shaped leaves. Most of the leaves are emergent, and provide shelter and shade for fish and invertebrates. Its yellow flowers can be seen throughout the summer, and it usually grows in water 1-3m deep. American pondweed is a long-leaved pondweed that’s leaves can sometimes still be seen during winter months.

Naid. Photo courtesy WLI.

Yellow water lilly. Photo courtesy WLI.



Fish LakeTrophic Status: OligotrophicSurface Area: 32 AcresMaximum Depth: 25 feet (7.6 meters)

Fish Lake is located in Lincoln County east of Bull Lake at an elevation of 1,278 meters.Surrounding land ownership is 100% State Trust Lands. Fish distribution includes brook trout andcutthroat trout. Fish Lake has one non-motorized public access site on the east side of the lake.

Temperature and oxygen profiles show that Fish Lake was weakly stratified during all of the summer sampling dates. Fall Hydrolab profiles show that the lake was evenly mixed during all sampling dates.

In the fall of 2013, road construction prevented access to the campground and lake access site. In 2015, fires prevented summer sampling.

Fish Lake’s 2011/2016 average calcium concentration was reported at 16.55mg/L classifying it as a low risk for zebra mussel colonization.

Volunteer Lori Curtis paddles on Fish Lake. Photo courtesy Walt Curtis.



Location: 48.67711 N, 114.7248 W



Halfmoon LakeTrophic Status: Oligo-mesotrophicSurface Area: 55 acresMaximum Depth: 20 feet (6.1 meters)

The drainage basin for Halfmoon Lake is dominated by glacial till (78%) with the remainder composed of the Grinnel argillite belt series (Ellis & Craft, 2008).

Halfmoon Lake is located in Flathead County northeast of Lake Five at an elevation of 884 meters. It is surrounded entirely by private land ownership. Fish species present include brook trout, largemouth bass, longnose sucker, pumpkinseed, and yellow perch. Halfmoon has one primitive non-motorized public access on the east end of the lake.

Temperature and oxygen profiles show that Halfmoon Lake was both weakly stratified and evenly mixed during summer sampling dates. Temperature profiles indicate Halfmoon Lake has been within the avoidance threshold range and leaning towards incipient lethal range for salmonids at depths of up to 6 meters during July and August.

Halfmoon Lake’s 2010, 2011, and 2016 average calcium concentration was 30.06mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 120mg/L.

Halfmoon Lake iced over in early November, 2013. Photo Courtesy WLI.



Location: 48.471735 N, 114.00292 W



Hanson-Doyle LakeTrophic Status: Meso-oligotrophicSurface Area: 8 acresMaximum Depth: 33 feet (10.1 meters)

The drainage area is dominated by the Ravalli group belt series (82%) with the remainder being glacial till on the valley floor (Ellis & Craft, 2008).

Hanson-Doyle Lake is located in Flathead County in the Tally Lake Ranger District at an elevation of 975 meters and is surrounded entirely by private land ownership. There is no public access to Hanson-Doyle Lake.

Temperature and oxygen profiles show that Hanson Doyle Lake has been stratified during summer sampling dates. Temperature profiles show that the lake has been within the avoidance threshold range for salmonids at depths of up to 5 meters during July and August. Oxygen profiles indicate that it has been between avoidance and anoxic concentrations when stratified at depths greater than 6meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 4-6 meters. Fall Hydrolab profiles show that the lake was evenly mixed during all sampling dates. Hanson Doyle is considered a warm water fishery and is connected to two other small lakes.

2011/2106 average calcium concentration was reported at 46.9mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 110mg/L.

Volunteer Jill Fanning lowers the Secchi disk at Hanson–Doyle Lake. Photo courtesy WLI.



Location: 48.35872 N, 114.467 W



Jette LakeTrophic Status: MesotrophicSurface Area: 31 acresMaximum Depth: 30 ft (9.1 meters)

Jette Lake has a basin area of 1,198 acres, and the drainage area lies entirely in the Ravalli group belt series (Ellis & Craft, 2008).

The lake is located in Lake County at an elevation of 1,143 meters and is surrounded entirely by private land ownership. Fish distribution records indicate a presence of cutthroat trout.

Temperature and oxygen profiles show that the lake was both stratified and evenly mixed duringsummer sampling dates. Temperature profiles show that Jette Lake has been within the avoidance threshold range for salmonids especially in 2012, and oxygen profiles show that the lake has beenbetween avoidance and anoxic concentrations at depths greater than 4 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 3-6 meters. Anoxic winter conditions resulted in a major fish kill during 2011/2012. Six benthic aerator diffusers were installed in the spring of 2012 to aid in maintaining oxygen concentrations suitable for salmonids. When anoxic conditions occur at the benthic interface an oxidation reduction potential exists andnutrients stored in the sediment can be liberated back into the water column given the right conditions. In early 2014, a winter hydrolab profile taken under the ice showed sufficient concentrations at the upper 2.5 meters to support salmonids. More sampling is needed to understand the effectiveness of the aerator installation. Pumpkinseed were introduced in 2014, and in 2016 hundreds of pumpkinseed were observed on their nests.

Jette Lake continues to rank highest among small lakes for total phosphorus, total persulfate nitrogen, and chlorophyll (a).

Jette Lake’s 2010, 2011, and 2016 average calcium concentration was 22.9mg/L classifying it as a moderate risk for zebra mussel colonization. The 2012 alkalinity level was reported at 110mg/L.



Location: 47.75985 N, 114.249269 W



Loon LakeTrophic Status: Oligo-mesotrophicSurface Area: 45 acresMaximum Depth: 40 feet (12.2 meters)

Loon Lake is located on the eastern side of the mission mountain range just west of the Swan Lake outlet on the valley floor. The geologic formation of the entire watershed is alluvium (Ellis & Craft, 2008).

The lake is located at an elevation of 945 meters. There is one non-motorized public access site on the north end of the lake. Temperature and oxygen profiles show that Loon Lake was stratified during summer sampling dates. Oxygen profiles show that it has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 7 meters. 2013 Hydrolab profiles show high temperatures approaching 75 degrees.

Loon Lake’s 2010, 2011, and 2016 average calcium concentration was 40.7mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 170mg/L.



Location: 48.022217 N, 113.988721 W



Lost Coon LakeTrophic Status: Oligo-mesotrophicSurface Area: 62 acresMaximum Depth: 14 feet (4.3 meters)

Lost Coon Lake is located in Flathead County near the Whitefish Lake Golf Course in Whitefish at an elevation of 960 meters. Surrounding land ownership is 100% private. No fishing access is available. It is a closed basin lake that is fed by groundwater with connectivity to Blanchard Lake during years with an extremely high water yield. Fish distribution includes black bullhead, northern pike, pumpkinseed sunfish, and yellow perch. There is no public access to Lost Coon Lake.

Temperature and oxygen profiles show that Lost Coon Lake was evenly mixed or weakly stratified during summer sampling dates. Temperature profiles indicate the lake has been within the avoidance threshold range for salmonids at depths of up to 3 meters during July and August, and historic oxygen profiles show that the lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 2 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 2-3 meters. Fall Hydrolab profiles show that the lake was evenly mixed during all sampling dates. Lost Coon Lake is considered a warm water fishery.

Lost Coon ranked second highest among all lakes for calcium in 2011 with concentration reported at 57mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level ranked highest among small lakes reported at 260mg/L.

Lost Coon Lake. Photo courtesy WLI.



Location: 48.39386 N, 114.35941 W



A macrophyte survey was conducted on Lost CoonLake on September 8, 2014. A total of 108 sites were surveyed for aquatic plants, shoreline plants and substrate. Plants that were commonly observedbut were not dominant include eel grass.

Shoreline plants in order of dominance:1) Cattail, 2) Carex, 3) Equisetum

Substrate composition for all sites was predominately gyttja. Lost Coon Lake has very dense macrophyte beds. Several springs exist, in which macrophyte composition changed primarily to mare’s tail and northern milfoil. American pondweed and yellow water lily’s floating leavesblanket the lake’s surface during summer/early fall.

Co-dominant Plant Species Composition Percentage of Co-dominant Slice

Bladderwort / Yellow Water Lily 46.67Bladderwort / American Pondweed 23.33Bladderwort / Northern Milfoil 6.67Bladderwort / Chara 3.33Bladderwort / Eel Grass / Variable Leaf Pondweed / Northern Milfoil 3.33Bladderwort / Chara / Yellow Water Lily 3.33Yellow Water Lily / American Pondweed 3.33Yellow Water Lily / Variable Leaf Pondweed 3.33Variable Leaf Pondweed / Common Water Moss 3.33Variable Leaf Pondweed / Flat Stem Pondweed 3.33

Lost Coon Lake

Dominant Plant Distribution September, 2014

Co-dominance

Bladderwart

No Plants Present

Chara

American Pondweed

Variable Leaf Pondweed

28%

22%14%

12%

10%

7%3%



Coontail (right) is an aquatic rootless perennial forb that is native to the United States and Montana. It is generally a dark or olive green color and forms dense colonies. Like EWM, Coontail reproduces through stem fragmentation. Coontail is often mistaken for Eurasian watermilfoil because of its ability to form dense colonies and the whorled leaves which resemble that of EWM. Coontail gets its name from the crowding of leaves at the end of branches which resemble a raccoon’s tail. Additionally, coontail prefers similar conditions as EWM including coarse or fine soil textures and is very tolerant of high water temperature and drought conditions. Coontail leaves are much coarser than EWM leaves and are toothed. Coontail makes excellent food for birds.

Common bladderwort (left) is a native aquatic plant that has floating stems that can grow 2-3 meters long. The stems of these branches have transparent bladders that capture tiny invertebrates. Bladderwort is found among many of the shallower oligo-mesotrophic lakes in the program.

Common bladderwart. Photo courtesy WLI.

Coontail. Photo courtesy WLI.



McGilvray LakeTrophic Status: OligotrophicSurface Area: 37 acresMaximum Depth: 33 feet (10.1 meters)

McGilvray Lake has a catchment area of 237 acres. The catchment is entirely glacial till (Ellis & Craft, 2008).

The lake is located in Flathead County at an elevation of 909 meters. Surrounding land ownership is primarily State Trust Land. Fish distribution records indicate a presence of largemouth bass, rainbow trout, and yellow perch. There is no public access to McGilvray Lake. Temperature and oxygen profiles show that McGilvray Lake was evenly mixed during all of theAugust summer sampling dates.

McGilvray Lake’s 2010, 2011, and 2016 average calcium concentration was 36.3mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 170mg/L.

Kids Fishing from the Stevlingson’s dock. Photo courtesy Don and Joy Stevlingson.



to develop trend information

Location: 48.14256 N, 114.0831 W



Murray LakeTrophic Status: MesotrophicSurface Area: 43.4 acresMaximum Depth: 100 feet (30.5 meters)

Murray Lake is located in Flathead County at an elevation of 3,572 feet. Surrounding land ownership is 100% State Trust Lands. Murray Lake was chemically treated with rotenone in October of 1999 to eliminate fathead minnow and redside shiners. Fish stocking records indicate a presence of rainbow trout and westslope cutthroat trout. There is one primitive public access site on the east side of the lake where motors are restricted to <10 horsepower.

Temperature and oxygen profiles show that Murray Lake was stratified during all of the summer sampling dates. Temperature profiles indicate that the lake has been within the avoidance threshold range for salmonids at depths of up to 5 meters during July and August. Oxygen profiles show that Murray Lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 11 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 5-12 meters. When anoxic conditions occur at the benthic interface an oxidation reduction potential exists and nutrients stored in the sediment can be liberated back into the water column given the right conditions.

Murray Lake often ranks among the highest of small lakes for total phosphorus and total nitrogen.Murray Lake ranked highest among small lakes in 2016 for Chlorophyll (a) but had dropped to 8th in 2017. Unfortunately, Chl(a) data was missing for 2018. Murray ranked 3rd for total nitrogen in 2018 and 4th for total phosphorus.

The 2011/2016 average calcium concentration was at 40.8mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 82mg/L.

A EWM survey was conducted near the public access site in 2011 and 2012. No EWM was found, however, Murray is the closest lake to Beaver Lake, making the threat of introduction very high.

Murray Lake looking back at the primitive boat launch. Photo courtesy WLI



Location: 48.44283 N, 114.45337 W



A macrophyte survey was conducted on Murray Lake on September 4, 2014. A total of 46 sites were surveyed for aquatic plants, shoreline plants, and substrate. Plants that were commonly observed but were not dominant include flat stem pondweed and Richardson’s pondweed.

Shoreline plants in order of dominance:1) Bulrush, 2) Carex, 3) Equisetum

Substrate composition in order of dominance: 1) Gyttja, 2) Boulder, 3) Gravel, 4) Bedrock, 5) Sand, 6) Cobble.

Murray Lake


Chara

No Plants Present

Yellow Water Lily

Co-dominace

39%

32%

25%

4%



Chara / American Pondweed 50Chara / Yellow Water Lily 50

Bulrush and horsetail are some of the most common emergent shoreline plants found among program lakes. Photo courtesy WLI.



Bulrush (right) is a perennial that can grow up to 4m tall. It is an important component of wetland ecosystems because it provides cover and food for wildlife. Most program lakes are home to bulrush. Loons have been observed using dense patches of bulrush as their nesting area on Blanchard Lake.

Water horsetail (left) is a rapid spreading perennial forb that has hollow stems that are grooved with 9-25 ridges that are banded with sheaths and teeth. Horsetail is found at many of the program lakes.

Heidi Sedivy (right) prepares to throw the rake at Murray Lake. Photo courtesy WLI.

Water horsetail. Photo courtesy WLI.

Bulrush. Photo courtesy WLI.



Peterson LakeTrophic Status: Oligo-mesotrophicSurface Area: 97 acresMaximum Depth: 30 feet (9.1 meters)

Peterson Lake has a catchment area of 304 acres and is entirely glacial till (Ellis & Craft, 2008).

The lake is located in Flathead County at an elevation of 914 meters. Surrounding land ownership is entirely private. Fish distribution records indicate a presence of lake whitefish, largemouth bass, northern pike, pumpkinseed, and yellow perch. During high water years, Peterson Lake is connected to Abbott Lake by a small waterway and can also be accessed via Echo Lake. Temperature and oxygen profiles show that Peterson Lake was evenly mixed or weakly stratified during summer sampling dates. Temperature profiles indicate that Peterson Lake has been within the avoidance threshold range for salmonids at depths of up to 7 meters during July and August. Oxygen profiles suggest that Peterson Lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 7 meters. Peterson Lake is considered a warm water fishery.

Peterson Lake’s 2010, 2011, and 2016 average calcium concentration was 29.3mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 150mg/L. In 2015, Peterson ranked second highest among small lakes for total phosphorus.

Volunteer John O’Cain at Peterson Lake. Photo courtesyJohn O’Cain.



Location: 48.120551 N, 114.05853 W



Skyles LakeTrophic Status: Oligo-MesotrophicSurface Area: 38 acresMaximum Depth: 16 feet (4.9 meters)

Skyles Lake has a drainage area of 1,260 acres. The drainage area is dominated by the Piegan group belt series (84%) with the remainder being composed of alluvium and glacial till (Ellis & Craft, 2008).

The lake is located in Flathead County 3 miles west of Whitefish on Highway 93 at an elevation of 975 meters. Surrounding land ownership is entirely private. The lake was chemically treated in the 1950’s to allow trout populations to flourish, but illegal introductions of sunfish and bass have dramatically influenced the fish community assemblage. Fish distribution includes largemouth bass, northern pike, pumpkinseed, sunfish, redside shiner, westslope cutthroat trout, and yellow perch. There is one primitive non-motorized public access that is difficult to find on the south side of the lake. Skyles Lake is the shallowest lake in the program at 4 meters.

Temperature and oxygen profiles show that Skyles Lake was evenly mixed during all of the summer sampling dates. Fall Hydrolab profiles indicate that the lake was evenly mixed during all sampling dates. Skyles is considered a warm water fishery.

Skyles Lake’s 2010, 2011, and 2016 average calcium concentration was 39mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 210mg/L. Amacrophyte survey was conducted in 2014. In 2015 and 2016, Skyles ranked highest among small lakes for total persulfate nitrogen.

Volunteer Cathi Lai rows to the monitoring location. Photo courtesy WLI.



Location: 114.05853 N, 114.401396 W



A macrophyte survey was conducted on Skyles Lake on September 2, 2014. A total of 100 sites were surveyed for aquatic plants, shoreline plants and substrate. Skyles is an algae dominated lake (chara).

Shoreline plants in order of dominance were:1) Bulrush, 2) Cattail, 3) Carex, 4) Equisetum

Substrate composition for all sites was predominately gyttja, followed by gravel, boulder and cobble.

Skyles Lake


Chara

No Plants Present

Co-dominance

76%

8%

16%



Chara / Filamentous Algae 87.5Chara / Yellow Water Lily 6.25Chara / Bladderwort 6.25



Chara or muskgrass is anchored green algae that are native to Montana that spends its entire life submerged without flowering. Chara is often referred to as muskgrass or skunkweed because of its foul odor. Because Chara is usually encrusted with carbonates, it typically feels crunchy to the touch. Skyles Lake is almost completely dominated by Chara.

Program Coordinator, Josh Gubits (right), surveys the lake and identifies plants on the rake. Both ocular surveys and rake throws were used to determine plant dominance. The maximum depth of the rake was 6.1m. Where lake depth exceeded 7.6m, the rake was not thrown and a data point was not recorded. All plants observed at each site were recorded, and rated on a scale of 1-5 for density.

Chara. Photo courtesy WLI.

A close up of chara. Photo courtesy WLI.

Josh Gubits of AquaTerra Solutions surveys lake vegetation. Photo courtesy WLI.



Spencer LakeTrophic Status: MesotrophicSurface Area: 30 AcresMaximum Depth: 18 feet (5.5 meters)

The geology of the catchment is a combination of the Piegan group belt series (58%), alluvium (23%) and glacial till (12%) (Ellis & Craft, 2008).

Spencer Lake is located in Flathead County, four miles west of Whitefish on Highway 93 at an elevation of 975 meters. Surrounding land ownership are State Trust Lands and private. The lake is stocked with largemouth bass. Fish distribution includes northern pike, pumpkinseed sunfish,westslope cutthroat trout, and yellow perch. There is no public boat access to Spencer Lake;however, it can be accessed from a pullout on Highway 93.

Temperature and oxygen profiles show that Spencer Lake was mixed during all of the summer sampling dates. Temperature profiles indicate that Spencer Lake has been within the avoidance threshold range for salmonids at depths of up to 4 meters during July and August. Fall Hydrolab profiles show that the lake was mixed or very weakly stratified during fall sampling dates. Spencer Lake is considered a warm water fishery.

Spencer Lake often ranks among the highest in small lakes for total persulfate nitrogen. In 2018, Spencer ranked the highest of the small lakes for total nitrogen, total phosphorus and Chlorophyll(a). Spencer Lake’s 2010, 2011 and 2016 average calcium concentration ranks highest among all lakes at 47.6mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level wasreported at 220mg/L.

Spencer Lake view from the Bar W Ranch. Photo courtesy WLI.



Location: 48.397442 N, 114.417273 W



A macrophyte survey was conducted on September 2, 2014. A total of 101 sites were surveyed for aquatic plants, shoreline plants, and substrate. Plants that were commonly observed but were not dominant include flat stem pondweed and Richardson’s pondweed.

Shoreline plants in order of dominance:1) Bulrush, 2) Cattail, 3) Carex, 4) Equisetum

Substrate composition for all sites was predominately gyttja, followed by gravel, boulder and cobble. Northern milfoil was discovered in Dollar Lake, making it a good candidate for Eurasian milfoil infestation.

esy

Spencer Lake


Chara

No Plants Present

Co-dominance

Yellow Water Lily

>20 ft Deep

54%

17%

9%

7%

6%



Yellow Water Lilly / Chara 22.22Yellow Water Lilly / Northern Milfoil 22.22Yellow Water Lilly / Chara / Bladderwort 11.11Northern Milfoil / Chara 11.11Northern Milfoil / Chara / Yellow Water Lily 11.11Northern Milfoil / Chara / Naiad 11.11Chara / Naiad 11.11

Emergent shoreline vegetation is very dense on the north end of the Spencer Lake. Photo courtesy WLI.



Northern milfoil is native to Montana and is found in nearly all program lakes. Eurasian watermilfoil, which is often confused with northern milfoil, is a non native invasive plant that roots itself to the bottom of water bodies and can grow in water up to 6 meters deep. It forms dense mats at the water’s surface shading out native plants, clogging boatmotors, and making swimming nearly impossible. Montana first discovered this plant in Noxon reservoir in 2007.

The easiest way to tell the two milfoils apart is to count the number of leaflets. Eurasian watermilfoil typically has at least 14 leaflet pairs per leaf. EWM has the ability to spread rapidly because it reproduces through stem fragmentation. Pieces the size of postage stamps that have broken off the main stem can reproduce. Eurasian watermilfoil is most commonly spread overland by boats that have not been cleaned between being in an infested water body and a non-infested water body. Eurasian watermilfoil has spread throughout Montana since it was first discovered in Noxon and Cabinet Gorge reservoir. Tosten Dam, Fort Peck Reservoir, the Jefferson River, and the upper and lower Missouri all have current infestations. In the fall of 2011,EWM was discovered in Beaver Lake just north of the town of Whitefish. Beaver Lake is the only program lake where EWM has been found.

Common water moss has rootlets that attach to woody debris and rocks. Fertilization and spore release occurs on the water’s surface. It prefers acidic water and requires a pH below 8.4. It is native, and is found in many of the program Lakes.

Northern milfoil (left) Eurasian water milfoil (right). Photo courtesy Heidi Sedivy.

Common water moss. Photo courtesy WLI.

Northern milfoil. Photo courtesy WLI.



Tetrault LakeTrophic Status: Oligo-mesotrophicSurface Area: 96 acresMaximum Depth: 49 feet (14.9 meters)

The catchment area of Tetrault Lake is composed of glacial till (65%) and glacial lake deposits (24%) (Ellis & Craft, 2008). Tetrault Lake is located in Lincoln County at an elevation of 843 meters. Surrounding land ownership is entirely private with the exception of one MFWP fishing access site. The lake is stocked with westslope cutthroat trout and rainbow trout. There is also a population of largemouth bass. There is one public access site which is restricted to motors <10 horsepower and is located on the south end of the lake.

Temperature and oxygen profiles show that Tetrault Lake was weakly stratified or stratified during summer sampling dates. Temperature profiles indicate that the lake has been within the avoidance threshold range for salmonids at depths of up to 8 meters during July and August. Hydrolab profiles show that the lake was mixed during fall sampling dates.

Tetrault Lake’s 2010, 2011 and 2016 average calcium concentration was 23.8mg/L classifying it as a moderate risk for zebra mussel colonization. The 2012 alkalinity level was reported at 170mg/L.

Volunteer Carol Blake fills out a data form on Tetrault Lake. Photo courtesy WLI.



Location: 48.945943 N, 115.114722 W



Upper Whitefish LakeTrophic Status: OligotrophicSurface Area: 80 acresMaximum Depth: 24 feet (7.3 meters)

Upper Whitefish Lake is located in Flathead County 25 miles north of Whitefish at an elevation of 41,387 meters. Surrounding land ownership is 100% State Trust Lands. The lake is stocked with westslope cutthroat trout. Fish distribution includes bull trout, longnose sucker, and westslope cutthroat trout. There is one motorized public access located on the northeast end of the lake.

Temperature and oxygen profiles show that Upper Whitefish Lake was weakly stratified during summer sampling dates.

The 2011/2016 average calcium concentration was reported at 19.7mg/L classifying it as a low risk for zebra mussel colonization. The 2012 alkalinity level was reported at 75mg/L.

Former Program Coordinator Eric Sawtelle at the public access to Upper Whitefish Lake. Photo courtesy WLI.



Location: 48.685611 N, 114.579648 W



Upper Whitefish Lake

A macrophyte survey was conducted on Upper Whitefish Lake on August 24, 2016. A total of 43 sites were surveyed for plants/algae. The northwest side of the lake was densely populated Richardson’s pondweed. Data collected indicated that roughly half of the shoreline has no plants present. There was very little plant diversity on Upper Whitefish Lake.

Upper Whitefish Lake

Dominant Plant Distribution September 2016

No Plants Present

Richardson's Pondweed

Northern Milfoil

Pondweed (Undistinguishable)

53%37%

7% 2%

Upper Whitefish Lake. Photo courtesy WLI.

Documents

5.7 SMALL LAKESwhitefishlake.org/wp-content/uploads/2020/06/NMLN_2018_Small-Lakes.pdfYellow water lily can be identified by itsheart shapedleaves. Most of the leaves are emergent,