Salmon are an essential component of the ecosystem in Tsleil-Waututh Nation’s traditional, ancestral, and unceded territory, centred on present-day Burrard Inlet, BC, Canada, where Tsleil-Waututh people have been harvesting salmon, along with a wide variety of other fishes, for millennia. Tsleil-Waututh Nation is an ancestral Coast Salish community that has called the Inlet home since time immemorial. This research assesses the continuity and sustainability of the salmon fishery at təmtəmíxʷtən, an ancestral Tsleil-Waututh settlement in the Inlet, over thousands of years before European contact (1792 CE). We apply Zooarchaeology by Mass Spectrometry (ZooMS) analysis to 245 archaeological salmon vertebrae to identify the species that were harvested by the Tsleil-Waututh community that lived at təmtəmíxʷtən. The results demonstrate that Tsleil-Waututh communities consistently and preferentially fished for chum salmon (Oncorhynchus keta) over the period of almost 3,000 years. The consistent abundance indicates a sustainable chum salmon fishery over that time and a strong salmon-to-people relationship through generations. This research supports Tsleil-Waututh Nation’s stewardship obligations under their ancestral legal principles to maintain conditions that uphold the Nation’s way of life.

All samples were analysed within the Ancient DNA and Proteins (ADαPT) Facility in the Department of Anthropology at the University of British Columbia. A total of 245 fish vertebrae were analysed using the method published in Buckley et al. 2009, modified as described in Richter et al. Briefly, ca. 10–30 mg of bone was subsampled and demineralized 0.6 M HCl at 4°C. Samples were rinsed in 200 μL of 0.1 M NaOH to remove humic compound, then rinsed three times in the same volume of 50 mM ammonium bicarbonate solution (NH4HCO3) pH 8.0 (AmBic). Samples were gelatinized through incubation in 100 μL of AmBic at 65 °C for 1 h at 65, before being enzymatically digested overnight at 37 °C in 0.4 μg of trypsin. Digested samples were acidified to 0.1% trifluoroacetic acid (TFA) and purified using Pierce™ 100 μL C18 tips (ThermoFisher). One microliter of α-cyano-hydroxycinnamic acid (matrix) was added to 1 μL of collagen extract and spotted in triplicate with onto a 384 spot MALDI target plate alongside calibration standards. MALDI-TOF was conducted on a Bruker Ultraflex III mass spectrometer with a Nd:YAG smart beam laser, with a SNAP averaging algorithm used to obtain monoisotopic masses (C 4.9384, N 1.3577, O 1.4773, S 0.0417, H 7.7583). Triplicate spectra were averaged and visually inspected using mMass software to identify diagnostic markers published in Richter et al. The raw MALDI spectra are uploaded here.