Nutrient concentrations in 59 Antarctic fur seal (Arctocephalus gazella) scats collected in 2022 in two colonies of the Kerguelen Islands, southern Indian Ocean

The dataset contains dry weight nutrient concentrations (20 nutrients, calcium Ca, phosphorus P, sodium Na, potassium K, magnesium Mg, strontium Sr, iron Fe, zinc Zn, copper Cu, manganese Mn, selenium Se, arsenic As, nickel Ni, cobalt Co, molybdenum Mo, chromium Cr, cadmium Cd, vanadium V, silver Ag, lead Pb) measured on 59 scat samples from Antarctic fur seals (Arctocephalus gazella) collected in Cap Noir (49°07’ S 70°45’ E) and Pointe Suzanne (49°44’ S 70°44’ E) colonies of the Kerguelen Islands (southern Indian Ocean), during austral summer 2021-2022. Samples were stored at -20°C within 48 hours of collection and until processing. In 2022, scat samples were individually thawed, cleaned of large plant debris, weighted and stored at -20°C before being freeze-dried for a minimum of 72 hours and ground to fine powder until analysis. All material was carefully rinsed with ultrapure water and ethanol between samples to avoid contamination. Total concentrations of major constitutive chemical elements in biological tissues (P, Ca, K, Na, Mg) were determined by inductively coupled plasma atomic emission spectrometry (ICP-OES, Vista-Pro Varian). Aliquots of samples (∼250 mg dry mass of homogenised powder) were digested using a 6:2 (v/v) mixture with nitric acid (HNO3 69%, Trace Metal Grade®, FisherScientific) and hydrochloric acid (HCl, 34%, Trace Metal Grade®, FisherScientific). Acidic digestion of the samples was performed over-night at room temperature and then in a microwave oven (START-D, Milestone). Finally, the digestats were diluted to 50 mL with ultrapure water before analyses with ICP-OES. Total concentrations of essential trace nutrients (As, Co, Cu, Fe, Mn, Ni, Se, Zn) were determined by inductively coupled plasma mass spectrometry (ICP-MS, ICAP-Qc ThermoFisher). Aliquots of samples (∼200 mg dry mass of homogenised powder) were placed in Teflon bombs and mineralized with a mixture of ultrapure HNO3 acid (PlasmaPure Plus grade, SCP Science®) and ultrapure water using a micro-wave (ETHOS-UP, Milestone). The digests were then diluted to 50 mL with ultrapure water before analyses with ICP-MS. The quality assurance of all metal analyses relied on blank and internal standard controls, and on the accuracy and reproducibility of data relative to the certified reference materials (CRMs) used in each analytical run. Blank values were systematically below the detection limits and CRM values concurred with certified concentrations. Results for the CRMs are provided in the dataset