Mesozooplankton are collected with plankton nets (typically a 71-cm diameter, 202-um mesh Bongo net) and samples flash frozen at sea in liquid N2 for subsequent shore-based measurements of dry weight biomass. Measurements are made by weighing pre-tared Nitex mesh on an analytical balance, for mesozooplankton size-fractionated into 5 different categories (> 0.2 mm, 0.5 mm, 1.0 mm, 2.0 mm, 5.0 mm). Biomass is expressed as dry mass of zooplankton per m3 of water filtered, or when multiplied by the maximum depth of the tow, as integrated dry mass of zooplankton per m2 of sea surface. Samples for dry weight biomass have been collected on CCE-LTER Process Cruises since 2006 and these collections are ongoing.