Mesozooplankton were collected with a MOCNESS net system during the oceanographic cruise JR16003 (Dec 2016 to Jan 2017). The MOCNESS comprised 9 separate nets which opened in sequence such that the closing of one net opened the next; net 1 was open during the descent of the net to its maximum depth (1000 m) while the remaining 8 depths opened at regular intervals during the reascent to the surface. All catches were immediately preserved in 4% buffered formaldehyde. Identification of taxa was performed by the Morski Institute (Poland). Specimens were categorised to the lowest possible taxonomic level, which, in some cases, encompassed developmental stages but, in other cases, was limited to higher order taxa. Each taxa was enumerated to determine abundance in units of individuals m-3. The dataset allows examination of the distribution and abundance of these species across Polar Frontal Zone in Southern Ocean Atlantic sector.

The survey was funded by The UK Natural Environment Research Council (NERC) and carried out as part of the POETS Wester Core Box and SCOOBIES programmes at British Antarctic Survey. The time of Geraint Tarling and the analysis of the MOCNESS nets was funded by the NERC grant "SeaDNA - Assessing marine biodiversity and structure using environmental DNA: from groundtruthing to food web structure and stability" NE/N00616X/1 PI: Stefano Mariani.