Wolf-Cougar Co-occurrence in the Central Canadian Rocky Mountains

Author

Ellen BrandellFollow

Graduation Year

2015

Graduation Month

May

Document Type

Thesis

Degree Name

Bachelor of Science – Forestry

School or Department

Wildlife Biology

Major

Wildlife Biology – Terrestrial

Faculty Mentor Department

Wildlife Biology

Faculty Mentor

Mark Hebblewhite

Keywords

cougar, wolf, competition, co-occurrence, occupancy

Subject Categories

Biology | Ecology and Evolutionary Biology | Population Biology

Abstract

Cougars and wolves are top carnivores that influence the dynamics of an ecosystem, including prey behavior and dynamics, and interspecific competition. Studies about the interactions between wolves and cougars typically find wolves are dominant competitors to cougars. We examined single-species, single-season occupancy models and co-occurrence models of wolves and cougars in the Central Canadian Rocky Mountains to understand interactions between these two species on a grand landscape. Data was collected from 2012-2013 using remote wildlife cameras and separated into seasons. Naïve occupancy estimates were larger for wolves in both seasons, but both species had smaller ranges in winter. There were only slight differences in environmental covariates for the single-species, single-season occupancy models, yet wolf occupancy estimates were still higher than cougars in both seasons. When wolves were species A in the co-occurrence models, results showed cougar occurrence and detection to be independent of wolf presence. However, when cougars were species A in the co-occurrence models, top models showed wolf occurrence and detection to be conditional on cougar presence. Overall, the top competing models in both seasons for either species A had some conditionality, yet no environmental covariates were significant in any co-occurrence model. These results are difficult to interpret; we suspect slight spatial separation between wolves and cougars in this study area, but further studies about smaller-scale competition could uncover more significant interactions between the two carnivores.

Honors College Research Project

1

Recommended Citation

Brandell, Ellen, "Wolf-Cougar Co-occurrence in the Central Canadian Rocky Mountains" (2015). Undergraduate Theses, Professional Papers, and Capstone Artifacts. 58.
https://scholarworks.umt.edu/utpp/58