RV Tangaroa carried out a 42-day research voyage to the Ross Sea from 29 January to 11 March 2015. The main purpose of the New Zealand-Australia Antarctic Ecosystems Voyage (TAN1502) was to undertake ecological studies of Ross Sea marine foodwebs of importance to top predators. The work was centred on the feeding areas of cetaceans, primarily blue whales and humpback whales, and in the Ross Sea slope area, which is the main fishing ground for the Ross Sea toothfish fishery. Whales were located using passive acoustics and visual observations. Observations of prey species were collected with multifrequency echosounders with associated midwater and demersal trawling. Associated oceanographic and atmospheric observations were made while underway. Samples of prey species and whale tissue (from biopsy) were collected for trophic (stable isotope) studies. Weather conditions during the voyage were excellent and all five science objectives were successfully completed. The voyage was supported by funding from Antarctica New Zealand (ANZ), the New Zealand Ministry for Business Innovation and Employment (MBIE), Australian Antarctic Division (AAD), and the National Institute of Water and Atmospheric Research Limited (NIWA).