摘要：We studied the St. Croix River from May to September 2000, sampling the water with surface plankton net tows. We found low water, low flow, and a warm environment and observed new surface plankton. We report a red alga. The surface plankton also contained the alga genera Oedegonium, Hydrodictyon, Elakatothrix, Selenastrum, Tetraedon, Ouadrigula, and Xanthidinium for the first time in our years of study. We also observed Synura, a chrysophyte, which had not been observed previously. We found many suctorian and amoeboid forms in the plankton, and we report the first continuous surface plankton observations of tardigrades.
