Disproportionate predation on endemic marmots by invasive coyotes

Invasive coyotes (Canis latrans) are the primary terrestrial predators of the endangered Olympic marmot (Marmota olympus) in Olympic National Park, Washington. Analysis of carnivore scat revealed that coyotes accounted for 71% of verified samples and were responsible for 85% of marmot predation events, with only bobcats (13%) and cougars (2%) contributing to the remainder. Genetic markers confirmed that nearly all identified coyote individuals preyed on marmots, indicating widespread and substantial predation pressure. Coyotes ranked fifth in their diet composition but were the dominant predator across seasons and regions, likely driving observed declines and local extirpations of this endemic species. The study used mitochondrial DNA analysis for carnivore identification and microsatellite markers to track individual coyotes, providing critical insights into the impact of invasive predators on native wildlife.

Witczuk, J., Pagacz, S., & Mills, L. S. (2013). Disproportionate predation on endemic marmots by invasive coyotes. Journal of Mammalogy, 94(3), 702–713. https://doi.org/10.1644/12-mamm-a-199.1