For stable isotope baseline measurements, the primarily herbivorous copepod Nannocalanus minor was collected during the research cruise SO285 on RV Sonne in the northern (nBUS) and southern (sBUS) Benguela Upwelling System between September 13 and October 9, 2021. The cruise was part of the TRAFFIC (Trophic tRAnsfer eFFICiency in the Benguela Current) project. Samples were retrieved from a vertical multinet "Midi" between 0 and 1000 m (200 µm mesh size). In total, six samples were obtained from the sBUS and three from the nBUS. Stable isotope measurements of the copepod were then used as baseline values for further analyses in the study.