Figure 1.

Representative example (25°C experiment) of the development of FISH-based V. cholerae non-O1/non-O139 concentrations in 800-ml microcosms amended with 0 (control), 50 and 150 cladocerans (Clad). a sterile filtered lake water (‘without initial competition’); b 2-μm filtered lake water (‘with competition’). Small inserts: development of the natural bacterial community (counted as total bacteria less V. cholerae non-O1/non-O139 cells) during the experiment. Error bars indicate the standard error of counts derived from 20 microscopic fields and are mostly smaller than the data point