The Influence of a Railway on Grizzly Bears (Ursus arctos) in Canada’s Rocky Mountain Parks

Grizzly bears (Ursus arctos) in Canada’s Rocky Mountain Parks are highly vulnerable to railway-associated mortality, with train collisions being the leading cause of recorded bear deaths. The Canadian Pacific Railway enhances vegetation diversity and productivity compared to adjacent forests, attracting bears due to higher sugar content and earlier ripening of forage plants like dandelions and spilled grain. Bears exhibit strong seasonality in railway use (spring and fall) and prefer rugged terrain near sidings, where movement is constrained. While prolonged rail use does not predict mortality hotspots, it occurs in areas with lower strike rates. Contaminant analysis revealed elevated levels of heavy metals and PAHs in railway-associated forage, particularly in spilled grain, though metal exposure did not correlate with increased rail use frequency. Mitigation strategies should focus on removing attractants (e.g., grain) and maintaining contaminated zones while enhancing safe foraging alternatives to reduce wildlife-train collisions.

Pollock, S. Z. (2019). The Influence of a Railway on Grizzly Bears (Ursus arctos) in Canada’s Rocky Mountain Parks [University of Alberta Library]. https://doi.org/10.7939/R3-GYY3-KX41