Abstract Analytical methods were used to determine the presence of animal residues contained in two humus samples collected from two pit features of a prehistoric Athapaskan archaeological site in the lower Mackenzie Valley of the Northwest Territories. These methods include gas chromatography, mass spectrometry, thin-layer chromatography and cross-over immunoelectrophoresis. Humus lipids from the pits showed evidence of cholesterol, arachidonic acid and nervonic acid, demonstrating the presence of residues from terrestrial and marine animals. Furthermore, positive reactions were obtained to Cervidae and bovine antisera. These findings allow us to better interpret the contents and functions of the pit features.