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Northwest Montana Lakes Volunteer Monitoring Network 2018 Program Summary

63 Whitefish Lake Institute

5.8 MEDIUM LAKES

(Surface Area 100-500 Acres)

BeaverBlaine

BlanchardFiveFoysGlen

HollandLower Stillwater

Murphy Rogers Sophie



Beaver LakeTrophic Status: Oligo-mesotrophicSurface Area: 144 acresMaximum Depth: 96 feet (29.3 meters)

Beaver Lake has a catchment area of 2,043 acres composed of the Piegan group belt series (46%) and alluvium (38%) (Ellis & Craft, 2008). Beaver Lake is located in Flathead County northwest of Whitefish on the northern edge of Lion Mountain. The lake’s elevation is 993 meters. Fish distribution records indicate a presence of brook trout, flathead minnow, rainbow trout and kokanee. The lake has one motorized public access site on the south side of the lake.

Temperature and oxygen profiles show that Beaver Lake was stratified during the summer sampling dates and has been within the avoidance threshold range for salmonids at depths of up to 7 meters during July and August. Oxygen profiles indicate that the lake has been between avoidance and anoxic thresholds for salmonids at depths greater than 10 meters. Anoxia has been observed at depths greater than 15 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. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 6-12 meters.

Beaver Lake often ranks high among medium lakes for total phosphorus, total nitrogen, and chlorophyll (a). Beaver Lake’s 2010, 2011, and 2016 average calcium concentration was 39.9mg/Lclassifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 82mg/L.

In mid-October 2011, Eurasian watermilfoil was discovered on Beaver Lake. The relatively small patch was found by DNRC near the boat ramp. This is the first lake in the Flathead basin to have a positive DNA for EWM. A multi-agency workgroup was established and addressed the issue by hiring a diver to evaluate the size of the infestation and deploy bottom barriers until the spring when the best management techniques were evaluated. In 2012, the bottom barriers were removed, and a suction dredge was used to remove as much EWM as possible. Prior to dredging, the Whitefish Lake Institute installed a sediment curtain near the outflow of Beaver Lake to help prevent EWM fragments from entering Beaver Creek which flows into Whitefish Lake. WLI removes and reinstalls the curtain seasonally. In 2014, only isolated plants were found, and in 2015 a little more than a pound of EWM was removed. In 2016, a few individual plants were found under a submerged log,and in 2017, two plants were found. No plants were found in 2018. Because of the real threat to Whitefish Lake and the watershed, suction dredging will continue indefinitely until there is confidence that EWM has been eradicated. WLI maintains a monitoring station on Beaver Creek as a part of their baseline monitoring program.

2018 Summer intern, Zach Cook, uses the Hydrolab on Beaver Lake. Photo courtesy WLI.



Location: 48.433507 N, 114.417221 W



Lake BlaineTrophic Status: Oligo-mesotrophicSurface Area: 382 acresMaximum Depth: 141 feet (43 meters)

Lake Blaine has a catchment area of 18,963 acres composed of glacial till (53%), Appekunney argillite belt series (36%) and glacial lake deposits (2%) (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 brook trout, kokanee, lake trout, largemouth bass, largescale sucker, longnose sucker, northern pike, northern pike minnow, rainbowtrout, sunfish, westslope cutthroat trout, and yellow perch. No formal public access exists on Lake Blaine; however, volunteers reported that a lakefront landowner allows informal public access on their property at the north end of the lake.

Temperature and oxygen profiles show that Lake Blaine was stratified during all summer sampling dates. Temperature profiles indicate that Lake Blaine has been within the avoidance threshold range for salmonids at depths of up to 6 meters during July and August. Oxygen profiles suggest that the lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 14 meters. Anoxia has been observed at depths greater than 15 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. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 7-14 meters.

Lake Blaine’s 2011/2016 average calcium concentration was reported at 33.2mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 130mg/L.

In 2011, volunteers reported higher than normal water elevations and more vegetation than ever observed. Two AIS reports were submitted to the website database for EWM in 2011. Montana Department of Agriculture (MDA) was contacted after the report was filed, and confirmed that theplant in question was not EWM. In 2012 and 2013, volunteers reported increased shore erosion from recreational boat use.

Lake Blaine panoramic. Photo courtesy Gayle Chaffey.



Location: 48.245208 N, 114.119476 W



Blanchard LakeTrophic Status: Meso-oligotrophicSurface Area: 143 acresMaximum Depth: 30 feet (9.1 meters)

Blanchard Lake has a catchment area of 2,649 acres. The geologic formations in the watershed are dominated by glacial till (54%) with the remaining area in the Piegan group belt series (Ellis & Craft, 2008).

The lake is located in Flathead County three miles west of Whitefish at an elevation of 969 meters.Fish stocking and population survey records indicate a presence of largemouth bass, northern pike, yellow perch, and pumpkinseed. Blanchard Lake has one motorized public access on the far north end of the lake.

Temperature and oxygen profiles show that Blanchard Lake was either stratified or weakly 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 6 meters during August. Oxygen profiles show that Blanchard Lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 6 meters. Blanchard Lake is considered a warm water fishery.

Blanchard Lake often ranks among the highest of medium lakes for total persulfate nitrogen. The lake’s 2011/2016 average calcium concentration was 39.5mg/L classifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 82mg/L.

An EWM survey was conducted near the public access site after the discovery in Beaver Lake. No EWM was found, however, northern milfoil was found throughout the lake. In 2012, what is believed to have been whorled milfoil was found. More surveying is recommended to confirm the types of milfoil species present in the lake. A Macrophyte survey was conducted in 2014 where fragrant water lily and yellow iris was found along much of the south west shore.

Former 2012 WLI intern Megan Powell from Westminster College in Salt Lake City, UT and volunteer Carol Treadwell-Steitz monitor Blanchard Lake. Photo courtesy WLI.



Location: 48.22668 N, 11422008 W



A macrophyte survey was conducted on Blanchard Lake on September 3, 2014. A total of 222 sites were surveyed for plants/algae. Dense macrophyte beds exist in Blanchard Lake and several plant species were found during the survey. Blanchard is considered a warm water fishery, and oxygen levels drop substantially during summer months after the lake becomes stratified.

Although northern milfoil was not a dominate plant, it exists throughout much of the lake. The pink teardrop icons on the map represent fragrant water lily, an invasive plant that was intentionally planted in Blanchard and other nearby lakes as an ornamental.

Blanchard Lake

Dominant Plant Distribution September, 2014

Co-dominance

Water Shield

Yellow Water Liliy

Bladderwart

>20 ft Deep

Chara

25%

24%

17%

11%

9%

7%3%

Co-dominant Plant Species Composition Co-dominant %

Yellow Water Lily /Bladderwart 20.75Water Shield / Bladderwart 11.32Yellow Water Lily / Bladderwart / Chara 9.43Yellow Water Lily / White Stem Pondweed 7.55Yellow Water Lily / Chara 5.66Bladderwart / Chara 5.66Northern Milfoil / Chara 3.77Yellow Water Lily / Bladderwart / Illinois Pondweed 3.77Other 32.08

Yellow water lily and water shield are emergent plants that have floating leaves. During the summer months these plants blanket the surface of Blanchard Lake. Photo courtesy Kim Schierl.



Fragrant water lily (left) is a non-native aquatic plant with large symmetrical white or pink blooms and heart-shaped glossy green floating leaves with a purple underside. The leafstalk is submerged andgrows out of large rhizomes which serve as a common food source for muskrats. The flowers range from 3-15 inches wide with several broad, curved petals that narrow toward the center. They are found in still, relatively shallow water (1.5-2 meters) lakes and ponds with silty beds. Native to the eastern portion of North America, its commercial popularity has caused its extensive dispersal throughout North America. The plant is now considered a secondary invader that can achieve extraordinary population growth and destabilize ecosystems.

Illinois pondweed (right) is a submerged plant that is native to Montana. Illinois has both submerged and floating leaves up to eight inches in length. Green flowers extend three inches from the water’s surface and are organized in whorls. Illinois pondweed is often confused with Richardson’s pondweed (native), and non-native curly leaf pondweed.

Curly-leaf pondweed (left) is an invasive aquatic perennial that is native to Eurasia, Africa, and Australia. It was accidentally introduced to United States waters in the mid-1880s by hobbyists who used it as an aquarium plant. The leaves are reddish-green, oblong, and about 3 inches long, with distinct wavy edges that are finely toothed. The stem of the plant is flat, reddish-brown and grows from .2- 1-meter long. The plant usually drops to the lake bottom by early July. CLP leaves resemble lasagna noodles. CLP infestationsdiscovered in several isolated patches in Flathead Lake and the Flathead River.

Fragrant water lily. Photo courtesy WLI.

Curly-leaf pondweed. Photo courtesy WLI.

Illinois pondweed. Photo courtesy WLI.



Lake FiveTrophic Status: Meso-oligotrophicSurface Area: 152 acresMaximum Depth: 62 feet (18.9 meters)

Lake Five’s drainage basin is dominated by glacial till (68%) with the remainder lying in the Grinnel argillite belt series (Ellis & Craft, 2008).

Lake Five is located in Flathead County in the Hungry Horse Ranger District at an elevation of 993 meters. Fish distribution records indicate a presence of brook trout, kokanee, largemouth bass, longnose sucker, northern pike minnow, pumpkinseed, rainbow trout, walleye, westslope cutthroat trout, and yellow perch. A new motorized public access site was constructed in the fall of 2011 on the southeast end of the lake.

Temperature and oxygen profiles show that Lake Five was stratified during summer sampling dates. Temperature profiles indicate that Lake Five has been within the avoidance threshold range forsalmonids at depths of up to 9 meters during August. Oxygen profiles show that Lake Five has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 13meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 9-13 meters.

Lake Five ranked highest among medium lakes for Chlorophyll(a) in 2018. In 2016, it also ranked highest for calcium. Lake Five’s 2010, 2011, and 2016 average calcium concentration was 42.4mg/Lclassifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 150mg/L. In 2015, Lake Five ranked highest among medium lakes for chlorophyll (a).

A visual survey for EWM was conducted in 2011 and 2012 along the shoreline yielding no suspect results. Additional surveying is recommended based on new ease of access and recreational use.

Photo: Volunteer Ron Ridenour and his dog Cody cruising on Lake Five.



Location: 48.46573 N, 114.012494 W



Foys LakeTrophic Status: MesotrophicSurface Area: 241 acresMaximum Depth: 134 feet (40.9 meters)

Foys Lake has a drainage basin of 1,836 meters. The basin area is dominated by the Piegan group belt series (86%) of the Salish Mountains with the remainder composed of glacial till (Ellis & Craft, 2008).

Foys Lake is located three miles southwest of Kalispell in Flathead County at an elevation of 106 meters. The lake is surrounded entirely by private land ownership. Fish distribution records indicate a presence of arctic grayling, kokanee, rainbow trout and redside shiner. Foys Lake has one motorized public access site located on the southeast end of the lake.

Temperature and oxygen profiles show that Foys Lake was stratified during summer sampling. The temperature profile indicate that Foys Lake was within the avoidance threshold range for salmonids at a depth of 7 meters during August. Oxygen profiles shows that the lake was between avoidance and anoxic concentration thresholds for salmonids at a depth greater than 17 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. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 8-15 meters.

Foys Lake consistently ranks among the highest of medium lakes for total phosphorus, total nitrogen,and chlorophyll (a). The lake’s 2010, 2011, and 2016 average calcium concentration was 3.8mg/L classifying it as a very low risk for zebra mussel colonization. The 2012 alkalinity level was reported at 700mg/L.

In 2011, 2012, and 2014 an EWM survey was conducted near the public access site yielding no suspect results. Very few macrophytes (aquatic plants) were found in the littoral zone during the surveys.

Volunteer Allen Gustafson prepares to collect a winter hydrolab profile blow the ice on Foys Lake. Photo courtesy WLI.



Location: 48.16738 N, 114.36279



Glen LakeTrophic Status: OligotrophicSurface Area: 301 AcresMaximum Depth: 40 feet (12.2 meters)

Glen Lake has a basin area of 4,839 acres composed of alluvium (65%) and the Piegan group belt series (Ellis and Craft, 2008).

Glen Lake is located in Lincoln County at an elevation of 914 meters. It has a surface area of 301 acres and a maximum depth of 40 feet. Surrounding land ownership is 100% private. Fish stocking records indicate a presence of kokanee and rainbow trout. There is also a population of yellow perch.

There is one motorized public access site located on the northeast side of the lake. Temperature and oxygen profiles show that Glen Lake was either evenly mixed or weakly 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 6 meters during July and August.

Glen Lake’s 2010, 2011, and 2016 average calcium concentration was 28.3mg/L classifying it as a moderate to high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 150mg/L.

Photo: Volunteer Guenter Heinz en route to the Glen Lake monitoring location. Photo courtesy WLI.



Location: 48.86221 N, 114.9481



Holland LakeTrophic Status: OligotrophicSurface Area: 414 acresMaximum Depth: 156 feet (47.5 meters)

Holland Lake has a basin area of 423 acres which is composed of both the Piegan group (39%) and Missoula group (32%) belt series and alluvium (20%) (Ellis & Craft, 2008). Holland Lake is located fifteen miles north of Seeley Lake in Missoula County at an elevation of 1,280 meters. Surrounding land ownership is entirely USFS. Fish distribution records indicate a presence of bull trout, kokanee, largescale sucker, longnose sucker, mountain whitefish, northernpike minnow, peamouth chub, rainbow trout, westslope cutthroat trout and yellow perch. Holland Lake has one motorized public access on the east end of the lake. The lake can also be accessed from the campground on the northern side of the lake.

Temperature and oxygen profiles show that Holland Lake was stratified during summer sampling. Temperature profiles indicate that the lake has been within the avoidance threshold range forsalmonids at depths of up to 6 meters during July and August.

Holland Lake’s 2011/2016 average calcium concentration was 21.2mg/L classifying it as a moderaterisk for zebra mussel colonization. The 2012 alkalinity level was reported at 77mg/L.

Volunteers Rob Rich and Bill Beers on Holland Lake. Photo courtesy WLI.



Location: 47.449659 N, 113.589013 W



Lower Stillwater LakeTrophic Status: Oligo-mesotrophicSurface Area: 250 acresMaximum Depth: 53 feet (16.2 meters)

Lower Stillwater Lake has a drainage area of 103,490 acres. Lower Stillwater Lake has the largest drainage area by far of all the medium sized lakes. The geology of the drainage area is composed of alluvium (37%) and the Piegan group (19%), Ravalli group (19%) and the Wallace formation (23%) of the belt series (Ellis & Craft, 2008).

Lower Stillwater is located in Flathead County 12 miles northwest of Whitefish on Highway 93 at anelevation of 975 meters. Surrounding land ownership are State Trust Lands and private. Fish distribution includes lake trout, mountain whitefish, northern pike, pumpkinseed sunfish, rainbow trout, westslope cutthroat trout, and yellow perch. There is one motorized public access site on the south end of the lake.

Temperature and oxygen profiles show that the lake was stratified or weakly stratified during summer sampling. Temperature profiles show that the lake has been within the avoidance threshold range for salmonids at depths of up to 3 meters during July and August. Oxygen profiles indicate that Lower Stillwater Lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 6 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 5-8 meters. Hydrolab profiles show that the lake was mixed during fall sampling dates.

Lower Stillwater Lake’s 2010, 2011, and 2016 average calcium concentration was 36.4mg/Lclassifying it as a high risk for zebra mussel colonization. The 2012 alkalinity level was reported at 130mg/L.

The lake was surveyed for EWM in 2012 and 2013. No EWM was found. A 2012 report of curly leaf pondweed was investigated and identified as Richardson’s pondweed.

Linda and Eric Sawtelle on Lower Stillwater Lake. Photo courtesy WLI.



Location: 48.520612 N, 114.556328 W



A macrophyte survey was conducted on Lower Stillwater Lake on August 27, 2016. A total of 56 sites were surveyed for plants/algae. No EWM was found in the survey, but because northern milfoil is the most dominate plant, it indicates that Lower Stillwater has favorable habitat for EWM. There was more plant diversity found on Lower Stillwater than any of the other lakes monitored in 2016. Dense mats of marigold, chara and pondweed on the north end of the lake were observed. There were also large quantities of filamentous algae observed on the east side of the islands.

Lower Stillwater Lake

Dominant Plant Distribution September 2016

Northern Milfoil

Chara

No Plants Present

Filamentous Algae

American Pondweed

Pondweed (Undistinguishable)

Marigold

Elodea

BladderwortYellow Waterlily

Sago Pondweed

Water Moss

38%

20%

13%

7%

5%

4%

4%

2%2%

2% 2% 2%

Panoramic of Lower Stillwater Lake. Photo courtesy WLI.



Murphy LakeTrophic Status: OligotrophicSurface Area: 141 acresMaximum Depth: 71 feet (21.6 meters) Murphy Lake has a drainage area of 3.066 acres. The geology of the drainage basin is a composite of alluvium (52%), Ravalli group belt series (26%) and the Piegan group belt series Ellis & Craft, 2008).

Murphy Lake is located in Lincoln County in the Kootenai National Forest of the Fortine Ranger District at an elevation of 960 meters. Surrounding land ownership is 100% USFS. Fish distributionincludes largemouth bass and northern pike. There is one primitive motorized access located on the north end of the lake.

Temperature and oxygen profiles show that Murphy Lake was evenly mixed or weakly stratifiedduring summer sampling. Temperature profiles indicate that the lake has been within the avoidance threshold range for salmonids at depths of up to 7 meters during July and August. Hydrolab profiles show that Murphy Lake was mixed during fall sampling dates.

Murphy Lake’s 2010, 2011, and 2016 average calcium concentration was 28.5mg/L classifying it as a high risk for zebra mussel colonization.

In 2011-2014 EWM surveys were conducted near the public access site yielding no suspect results, however, northern milfoil was found throughout the lake. Additional visual surveying is recommended based on ease of access, recreational use, and number of macrophytes present.

Murphy Lake boat ramp with informational signage on AIS. Photo courtesy WLI.



Location: 48.73497 N, 114.85892 W



Rogers LakeTrophic Status: Meso-oligotrophicSurface Area: 239 acresMaximum Depth: 19 feet (5.8 meters)

Rogers Lake has a drainage area of 3,066 acres. The catchment is dominated by the Wallace formation belt series (75%) with the rest as glacial till (Ellis & Craft, 2008).

Rogers Lake is located in Flathead County at an elevation of 1,219 meters. This is the shallowest of the medium sized lakes included in the program. Surrounding land ownership is primarily privateand Forest Service. Fish distribution records indicate a presence of arctic grayling, redside shiner, and westslope cutthroat trout. There is one primitive motorized public access located on the north end of the lake.

Temperature and oxygen profiles show that Rogers Lake was evenly mixed during summer sampling. Temperature profiles indicate that the lake has been within the avoidance threshold range for salmonids at depths of up to 5 meters during August. Oxygen profiles vary considerably from year to year. Hydrolab profiles show that Rogers Lake was mixed during summer sampling dates.

Rogers Lake often ranks among the highest of medium lakes for total phosphorus and chlorophyll (a). The lake’s 2010, 2011 and 2016 average calcium concentration was 20.8mg/L classifying it as a moderate risk for zebra mussel colonization. The 2012 alkalinity level was reported at 81mg/L.

A EWM survey was conducted in 2012 and 2013 near the public access site yielding no suspect results, however, northern milfoil was found throughout the lake. Additional visual surveying is recommended based on ease of access, recreational use and number of macrophytes present. In 2015, Rogers Lake ranked highest among medium lakes for total phosphorus but levels have decreased since then.



Location: 48.067059 N, 114.604093 W



Sophie LakeTrophic Status: Oligo-mesotrophicSurface Area: 221 acresMaximum Depth: 70 feet (21.3 meters)

Sophie Lake is located in Lincoln County four miles northwest of Eureka on Highway 37 at an elevation of 792 meters. Surrounding land ownership are State Trust Lands, MFWP, and private. Fish stocking records indicate a presence of rainbow trout and kokanee. Population surveys also found bluegill, bull trout, largescale suckers, northern pike, and northern pike minnow. There is one motorized public access site located on the south end of the lake. Due to high water, the public access, dock, and campground were flooded in the spring/summer of 2011and 2012.

Temperature and oxygen profiles show that Sophie Lake was stratified or weakly stratified duringsummer sampling. Temperature profiles indicate that the lake has been within the avoidance threshold range for salmonids at depths of up to 5 meters during July. Oxygen profiles show that Sophie Lake has been between avoidance and anoxic concentration thresholds for salmonids at depths greater than 13 meters. Depth profiles suggest that the ideal depth for salmonid habitation during summer months is between 6-12 meters.

Total phosphorus and Chlorophyll(a) levels were noticeably higher for Sophie Lake in 2018. Sophie Lake’s 2010, 2011, and 2016 average calcium concentration was 23.1mg/L classifying it as a moderate risk for zebra mussel colonization. The 2012 alkalinity level was reported at 110mg/L. A EWM survey was conducted in 2012 near the public access site yielding no suspect results, however, northern milfoil was found throughout the lake. Additional visual surveying is recommended based on ease of access, recreational use, and number of macrophytes present.

Volunteer Barb Hvizdak on Sophie Lake. Photos courtesy WLI.



Location: 48.963502 N, 115.115744 W

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