Trophic ecology of squids in the Benguela Upwelling System assessed through stomach content, fatty acid and stable isotopes analyses in austral spring 2021 - Stable isotope baseline measurements

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 15 and October 7, 2021. The cruise was part of the TRAFFIC (Trophic tRAnsfer eFFICiency in the Benguela Current) project. Samples were retrieved from vertical multinet "Midi" hauls (200 µm mesh size) at 1 station in the nBUS (0–50 m depth) and 2 stations in the sBUS (50–100 m and 0–50 m depth respectively). In total, 3 samples were obtained from the nBUS and 6 from the sBUS. Stable isotope measurements of the copepod were then used as baseline values for further analyses in the study.