According to historical ecology, səl̓ilw̓ət (Burrard Inlet) near Vancouver, British Columbia (BC), was once a highly productive zone sustaining successful and diverse clam and fish populations. However, since European contact in 1792 and subsequent intense industrialization, pollution and environmental degradation have negatively impacted its long-term inhabitants, Tsleil-Waututh Nation (TWN), by both contaminating and reducing the abundance of these traditional foods. In response, TWN is currently leading a large-scale project in collaboration with BC’s Ministry of Environment and Climate Change Strategy to collect reliable data, improve water quality guidelines and protect the cultural values associated with marine waters and tributaries. Leaning on shared priorities, we have collaborated in a novel study investigating the biogeochemical variability in modern and archaeological clam (Saxidomus gigantea and Leukomea staminea) shells and the potential of using geochemical proxies to investigate long-term food web dynamics. Particularly, oceanographic data collected by TWN and collaborative partners were used to establish if geochemistry in shells responded to seasonal phytoplankton blooms. Results indicate that trace elemental barium- and lithium-calcium ratios in shell calcium carbonate layers fluctuate seasonally related to different phytoplankton blooms in both clam species, with intensities of blooms also being reflected in these shell elemental ratios peaks. Using this proof-of-concept, we show how phytoplankton dynamics have shifted since colonization and industrialization. We conclude with personal reflections on the success of this collaborative study. This research is in collaboration with TWN but is not representative of TWN.