When yellow leaves of red mangrove are placed into the water near mangrove stands, they are rapidly occupied by marine oomycotes. This is data for frequency of Halophytophthora vesicula. The white circles are for leaf samples (small disks) that were surface "sterilized" (treated to kill most surface microbes) before culturing to detect presence of oomycotes. The black circles are for leaf samples that were not surface "sterilized". The small difference between the two trajectories shows that the occupying oomycotes were moving rapidly inside of the leaf tissue, reaching 100% frequency in about one diel period. See Newell & Fell, 1997, Competition among marine oomycotes, and between oomycotes and other microbes, Aquat. Microb. Ecol. 12:21-28, and references therein.