Modified spaces and ecological traces: Pacific yew and legacies of Indigenous landscape management on the central coast of British Columbia

Background/Question/Methods

Indigenous peoples have modified landscapes in ways that alter local ecology since time immemorial, including transplanting and tending plant species and introducing marine subsidies into nutrient-poor soils. In coastal British Columbia, the impacts of these processes on ecosystem productivity and community composition continue into the present, over 120 years since continuous occupation of sites ended due to colonization. Although a growing body of work is integrating Indigenous management into ecological studies at the community level, much less is known about Indigenous management influences on individual and rarer species of cultural importance like Pacific yew (Taxus brevifolia). A non-dominant understory tree and shrub that grows almost exclusively in old-growth forests, Pacific yew is of value to many First Nations but has received little ecological study. This research investigates the impacts of long-term Indigenous habitation on the size and abundance of Pacific yew on the territory of the Heiltsuk First Nation. We compared the size and abundance of Pacific yew on habitation sites that were occupied intensively by the Heiltsuk Nation to paired control sites that received little to no sustained use.

Results/Conclusions

Although this paired site method has detected the impacts of Indigenous modification on other species in prior studies, we found that landscape use histories were not a strong driver of patterns of tree size, nor were tree habitat conditions. Patterns of Pacific yew abundance were largely driven by site aspect impacting light availability during tree reproduction, and not by landscape use histories. This illustrates Pacific yew’s different response to landscape modification than other culturally important species and highlights the need for nuanced understanding of the diversity of management strategies employed by First Nations. These findings also shed light on the habitat preferences of Pacific yew, which have rarely been studied in this region.