Wahleach Project Water Use Plan Wahleach Reservoir ... - BC Hydro

Wahleach Reservoir had lower total zooplankton densities in comparison to several
other oligotrophic BC lakes (Table 7). From 2004 to 2006, Wahleach Reservoir had
the lower total zooplankton density than Arrow Lakes Reservoir and Kootenay Lake,
and similar densities as found in Alouette Lake. While densities of the zooplankton
assemblage were low relative to other systems, the biomass concentrations in 2006
were similar.
Table 7. Seasonal average zooplankton density, biomass and percentage of Daphnia
in zooplankton community in Wahleach Reservoir, Alouette Lake, Upper and Lower
Arrow Lakes Reservoir and the North and South Basin of Kootenay Lake in 2004-2006.
Values from other lakes are shown for comparison. Values are seasonal averages,
calculated for samples collected between April-November in Arrow and Kootenay
Lakes.
density (#·L -1 ) biomass (μg·L -1 )
2004 2005 2006 2004 2005 2006
Total
Wahleach 4.7 3.5 10.0 20.2 23.1 54.5
Alouette 5.9 4.2 11.5 14.9 20.3 89.9
Upper Arrow 14.3 6.7 11.6 22.4 10.4 28.0
Lower Arrow 28.7 18.9 18.6 36.0 37.2 78.0
Kootenay North 24.8 20.4 24.8 52.9 41.9 75.9
Kootenay South 28.6 20.0 24.3 54.7 43.5 73.3
Daphnia
Wahleach 0.8 0.9 2.3 11.9 12.2 31.5
Alouette 0.00 0.6 2.7 0.03 11.29 58.41
Upper Arrow 0.1 0.1 0.6 2.05 1.18 11.49
Lower Arrow 0.3 0.9 2.3 6.29 14.82 54.63
Kootenay North 0.3 0.3 1.7 6.07 5.28 37.25
Kootenay South 0.4 0.6 1.5 6.37 10.14 35.42
Daphnia %
Wahleach 17 26 28 59 53 58
Alouette 0 14 23 0 56 65
Upper Arrow 1 1 5 9 11 41
Lower Arrow 1 5 12 11 40 70
Kootenay North 1 1 7 11 13 49
Kootenay South 1 3 6 12 23 48
Wahleach Reservoir Fertilization Project, 2004-2006.
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