Unusual bloom of star-like prosthecate bacteria and filaments as a consequence of grazing pressure.

In seawater used for shrimp aquaculture in French Polynesia, the grazing of small bacteria (rods and coccoids) allowed the growth ofAncalomicrobium cells (to more than 2×10(6) cells ml(-1)) and large filaments > 10μm in length (5×10(6) cells ml(-1)). Their contribution to the increase in total bacterial number after grazing was 27.8 and 9.8%, respectively. These large bacteria are not grazed on by microflagellates, but are available for mesoplankton larvae.