Department of Biology, Reed College, Oregon, United States
Abstract: Urbanization is a widespread and growing instance of global change that affects ecosystem dynamics on multiple levels, negatively impacting certain species while creating new ecological opportunities for others. Coyotes, a generalist predator, inhabit urban spaces that have different resources, predator populations, and occurrences of human wildlife interactions than natural and forested areas. In order to protect and manage thriving wildlife populations while preserving natural habitat patches in urban landscapes, it is necessary to better understand what gives some species an adaptive advantage over others. In this study, I aimed to unfold how habitat fragmentation, anthropogenic resources, and interspecific competition impact coyotes’ foraging success by comparing the dietary niche of urban and nonurban coyotes. During Fall of 2022, I collected coyote scat samples from three urban and three non-urban habitats throughout the Willamette Valley and West of the Cascade Mountain Range. I used gross fecal analysis paired with natural abundance stable isotope analysis to examine dietary composition and nutrient consumption in urban and non-urban coyotes.
Insignificant differences in gross fecal analysis data between urban and non-urban locations suggest that neither habitat fragmentation nor interspecific competition between coyotes and larger predators interfere with coyotes’ ability to hunt and forage for sufficient prey and plants. However, the presence of garbage in urban coyote scat suggests a more anthropogenically influenced diet than that of non-urban coyotes. Stable isotope analysis suggests comparable 𝛿15N signatures and C:N ratios between coyotes inhabiting urban and non-urban habitats, refuting the hypotheses that trophic niche and diet quality differ between the two populations. Comparable trophic niches between coyote populations imply that, despite habitat fragmentation and anthropogenic influence, coyotes can be successful in foraging for a diet that is qualitatively similar to non-urban environments. This ability to adapt to changing resource availability supports the widely accepted notion that coyotes are among the most resilient wildlife species to global change. Future research should seek to explore food web variation across a variety of urban gradients to account for the impact of different markers of human footprint on the performance of different species.
