Reservoir Plankton Communities 
99 
Table 5. Results of correlation analyses between biomass of selected zoo- 
plankton taxa, densities of selected phytoplankton taxa, and water 
temperature, at Sutton Reservoir during 1985. 
Total Water 
phytoplankton 
Chlorophyceae Cya 
nophyceae 
temp. 
Copepoda 
-0.72 
-0.60 
-0.60 
-0.57 
0.008 
0.038 
0.037 
0.04 
Cladocera 
-0.75 
-0.76 
-0.77 
-0.65 
0.005 
0.004 
0.003 
0.020 
Rotifera 
0.57 
0.62 
0.45 
0.26 
' 0.051 
0.032 
0.139 
0.415 
D. ambigua 
-0.82 
-0.75 
-0.73 
-0.57 
0.001 
0.005 
0.007 
0.054 
B. coregoni 
-0.66 
-0.36 
-0.45 
-0.37 
0.018 
0.253 
0.14 
0.228 
Water temp. 
0.43 
0.71 
0.93 
1.00 
0.159 
0.009 
0.001 
0.000 
* Results listed as correlation coefficients (r)/ probability (p) 
Significantly greater densities of copepods and rotifers were 
captured at a pelagic station as opposed to near shore. This was a result 
of greater densities of E. affinis and D. dorsalis of the copepods and 
Brachionus havanaensis, B. plicatilis, Keratella americana , K. cochlearis, 
and K. valga at the pelagic station. 
Correlation analyses indicated a strong, inverse relationship between 
crustacean zooplankton (copepods and cladocerans) and phytoplankton. 
Zooplankton grazing is suggested as a major controlling factor for 
phytoplankton population dynamics with water temperature or nutrient 
availability probably controlling the cyanophyceae. 
ACKNOWLEDGMENTS.— I thank M. A. Pamperl and K. G. 
Stone for phytoplankton data, M. M. Smart for chemical limnology 
data and advice, and B. A. Carter and D. H. Schiller for sample 
collection. The figures were produced by S. P. Price and the manuscript 
was typed by members of the CP&L Harris Energy & Environmental 
Center Word Processing Subunit. 
