Fig. S8.

Frequency distribution for the encounter rate of single bacteria (either motile or nonmotile) with diatom lysis events, for three assumed diatom lysis rates corresponding to typical coastal conditions (1.4 lysis events per mL per h), a phytoplankton bloom (13 lysis events per mL per h), and a bloom collapse (38 lysis events per mL per h). These conditions correspond to a mean encounter rate of 1 per d, 10 per d, and 31 per d, respectively (as indicated by the arrows). Given the independent random occurrence of lysis events, all locations are equally likely to experience phycospheres. Thus, under our assumptions, the encounter rate with phycospheres is the same for motile and nonmotile cells.