Mesozooplankton distribution and copepod grazing in the Subtropical Atlantic near the Azores: Influence of mesoscale structures

Mesozooplankton distribution and copepod grazing were investigated in the S ubtropical Atlantic Ocean near the Azores during the AZORES I (August) and II (April-May) cruises. Mesozooplankton biomass and abundance remained low throughout the region, but significant increases were found related to the presence of the Azores Front. The Azores Front also exhibited maximum value s of copepod community ingestion, reaching 250 mg C m(-2) ingested daily. T his increase in ingestion was related to increases in copepod abundance, bu t not in copepod gut contents. Alb relationship was found between gut conte nts, or ingestion, and phytoplankton biomass or production. Daily cycles we re found in copepod gut contents, being higher during the night, but not in copepod abundance. Multidimensional scaling analysis revealed differences in copepod taxonomic composition between both sides of the front. During sp ring, daily copepod ingestion represents an average of 6% of the integrated chlorophyll (Chl) a concentration and 22% of the primary production. These percentages increase to 15% of Chl and 61% of production if we only consid er large (>2 mum) phytoplankton. No clear influence of the cyclonic eddy LE TICIA was found in mesozooplankton biomass or grazing. A significant effect of the Great Meteor Tablemount was found in copepod abundance and grazing, with higher values located west of the mount.