Thicker shells reduce copepod grazing on diatoms

The diatom frustule provides partial protection against copepod grazing. Whether the defense is due to cells being de-selected or handled for so long that grazers lose time foraging unknown. mechanism has implications population dynamics of both defended and co-occurring, undefended nutrient competitors. We use video-observations demonstrate thick-shelled diatoms captured by Temora longicornis were rejected more frequently than thin-shelled diatoms, irrespective cell size. larger much longer, spent handling these limits consumption phytoplankton. This may be why many even in presence dense grazer populations, reach bloom concentrations, thus, facilitate aggregation mass sedimentation. carbon sequestration securing a large at depth ready colonize pelagic, when growth conditions again become favorable.