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Ian Faurot Elise LaVanaway Scott Paradis Cody Settles

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What we know Small, circular lake with rapid drop-off No inflow, year-round outflow Frozen in winter Abundant population of bullhead (Ameiurus sp.) and a stocked rainbow trout population Extensive macrophytes

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What we want to learn Lake classification and origins Productivity Sediment composition Habitat quality Biological community Potential concerns

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What we need to sample To assess Blue Lake, we need Physical parameters: bathymetric map, irradience, temperature, maximum and mean depth, water and sediment volume, sediment profile and composition Chemical parameters: total and dissolved phosphorous*, specific conductivity, and dissolved oxygen profiles Biological parameters: primary production, zooplankton community, littoral and benthic invertebrates

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A B D C Study Area East side of lake 4 sampling sites

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Methods and Materials: Bathymetry A boat with a depth finder and GPS was taken in even transects across the lake, north to south and east to west, to obtain a bathymetric profile

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Methods and Materials: Physical properties Photic zone/irradience Temperature Oxygen content Conductivity

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Methods and Materials : Chlorophyll Only photic zone sampled 3 replicates of integrated samples at our 4 sites Chlorophyll calculated with photo-spectrometer BF Environmental Consultants Inc.

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Bathymetric Map Volume 58877 m 3 Sediment volume 6873 m 3 Surface area 10532 m 2 Maximum depth 10.22 m Mean depth - 5.59 m Sediment depth -.57m

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Photic zone Secchi depth 2 m Li-cor photometer estimate of photic zone 5.69 m Extinction coefficient 0.81

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Temperature profile Mean temperature 8.99 C Expect inverse stratification in winter Direct stratification in summer

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Dissolved oxygen Somewhat low for good trout habitat Potentially a problem with anoxia

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Specific conductivity Measured in micro-seimens per cm. A measure of TDS

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Chlorophyll-a Chlorophyll levels seem moderate Little significant variation across lake

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Conclusions Blue lake formed by glacial activity Kettle Lake Mesotrophic, Dimictic classification Chlorophyll A 3.16 0.94 g/L TP: 16.94 10.81 g/L, SP: 16.73 10.07 g/L Temp: 8.99 C DO: 2.93 mg/L Organic sediment content slightly higher than mineral content

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Recommendations Avoid input of any fuel, fertilizer, sewage. Reduce levels of bullhead spawn in lake Catch and Keep? Continue to stock rainbow trout Spawning/Trophic Cascade Continue study on lake in spring/summer Oxygen levels

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Literature cited Bettoli, P.W., M.J. Maceina, R.L. Noble, and R.K. Betsill. Response of a reservoir fish community to aquatic vegetation removal. North American Journal of Fisheries Management 13:110-124. Gall, G.A.E. and P.A. Crandell, 1992. The rainbow trout. Aquaculture 100:1-10. Wetzel, R. G. 2001. Limnology - Lake and River Ecosystems (3rd ed) Academic Press. Wilhelm, F. 2010a. Fish 415 Limnology, Spring Valley Lab Handout. University of Idaho, Moscow, Idaho. Wilhelm, F. 2010b. FISH 415 Limnology, Zooplankton Identification Lab. University of Idaho, Moscow, Idaho.