Microzooplankton feeding impact in a coastal upwelling system on the NW Iberian margin: The Ría de Vigo

► Microzooplankton consumes a significant fraction of plankton in the Ría de Vigo. ► Consumption of small heterotrophs relatively constant through the year. ► Consumption of diatoms very important during upwelling conditions. ► During non-upwelling, the microbial food web basicaly sustained by the microbial loop. ► In upwelling, the classical must coexist with the microbial food web based on diatoms.