Cougar Science Team reviews the science related to human-cougar interactions
A high-level excerpt of literature-review findings
Jan. 24, 2022
Understanding the interactions between humans and cougars (Puma concolor) presents unique challenges for wildlife managers. And, reducing these interactions, particularly those that lead to conflict, is a priority for the Washington Department of Fish and Wildlife (WDFW) and other wildlife management agencies throughout the United States.
Based on conversations with the Fish and Wildlife Commission, WDFW formed a team to review the scientific literature on human-cougar interactions and assess the factors that increase or mitigate risk of human-cougar conflict.
For the past 10 months, a team, comprised of WDFW staff and external scientists, has been reviewing an extensive body of research to assess both the analytical and ecological merits of current literature, focusing on data and methods, to summarize the current state of knowledge about human-cougar interactions, and factors affecting these interactions. You can find the full report on WDFW’s website.
Who was on the panel?
The Science Review Team consisted of scientists whose roles include cougar research and management or who brought unique skills related to the assessment of scientific methods and literature. The primary criteria for external team members were that they had experience with cougar research and management, had strong research design skills, or had exceptional quantitative skills. The 10-member review team consisted of six WDFW Wildlife Program scientists and four external scientists from Idaho Fish and Game, Oregon Department of Fish and Wildlife (retired), Colorado Parks and Wildlife, and the U.S. Geological Survey.
What was your method for reviewing literature?
The team used several approaches to identify scientific literature for their review to reduce the risk of missing important publications.
The process yielded a final master list of 96 papers, 87 of which reported the results of investigations of cougar ecology and behavior and nine pertained to public knowledge, perceptions, and attitudes about cougars. The research objectives of the 87 ecological papers and their subsequent applicability to our review varied widely, so the team used five criteria to assign each paper to one of four categories, reflecting the direct relevance to the topics of cougar-human interactions and cougar use of areas with residential development. The team also assigned literature to several topical questions guiding their review.
What questions did you ask in your literature review?
We assessed the following eight questions in our literature review.
· Do cougar removals through recreational hunting and/or agency conflict response affect levels of cougar-human interaction?
· Does cougar abundance or population trajectory affect cougar-human interaction levels?
· Does the abundance, diversity, and/or distribution of prey affect cougar-human interaction levels?
· Do preventative measures, such as nonlethal deterrence, quality husbandry, and outreach/education/information sharing affect levels of cougar interactions with people?
· Do landscape characteristics (e.g., residential development levels and/or patterns, habitat type, connectivity) affect cougar-human interaction levels?
· Does the number of people living, working, or recreating in cougar habitat affect the level of cougar-human interactions?
· Is the number of conflict reports/complaints correlated with actual frequency of conflicts (i.e., is there published evidence that, with no change in real conflict, complaints may increase because of social tolerance or change in human perceptions [e.g., trail or doorbell camera use, news reports, etc.])?
· Does the presence of other large carnivores, notably wolves, affect cougar proximity to, or levels of interactions with, people?
What were your findings?
Our review concluded that the roles of cougar removals; cougar population size; the abundance or diversity of prey; human population size, distribution, or recreation levels; human attitudes, and competition with other large carnivores in human-cougar interactions remain uncertain, due mostly to limited or poor data and shortcomings in analytic methods used.
The team found the studies evaluating the effectiveness of nonlethal deterrents provided some evidence that these methods reduce conflict. Their review of papers investigating the role of landscape characteristics revealed spatial ecology to be the most reliably studied and best understood piece of cougar wildland-urban ecology.
When humans and cougars interact, it typically happens at the wildland-urban interface or in exurban (areas just outside suburbs) and rural residential settings immediately adjacent because these habitats provide both abundant native prey and cover, features attractive to cougars. In addition, interactions can happen in places that have enough native landcover, connectivity to wildlands, and prey to support cougar use, but with a minimal human presence level that does not substantially deter cougars.
The team identified only a limited number of studies that directly addressed the human-cougar questions we are asking in our review. Much of the literature we reviewed was derived from unplanned mining of pre-existing data that had been collected for other routine reasons, data were often not assessed for accuracy, and some factors were inadequately addressed. Consequently, most hypotheses about factors influencing human-cougar conflict have not been rigorously tested; well-designed research is still needed to better understand the factors affecting cougar interactions with people. Because wildland-urban systems are complex, and interactions encompass both cougar and human behavior, the team recommend the use of long-term studies that incorporate both ecological and human-caused factors to address management questions.
In addition to the literature review, the panel developed some recommendations for future research.
More background about cougars in Washington
The cougar is one of the most adaptable and successful large carnivores on the planet. The fourth-largest cat in the world and the second-largest in the western hemisphere, cougars range from the southern tip of Chile to northern British Columbia, Canada, and they are well-adapted to a diverse array of ecosystems.
In Washington, cougars are classified as a big-game species managed under regulations that allow for harvest, and cougars are managed for population and social stability. In Washington, cougars occupy about 104,000 km2 of suitable habitat, of which, WDFW regulates cougar over ~91,000 km2.
Cougars are an obligate carnivore (i.e., their survival requires animal prey) and their distribution is largely dependent on food availability. Deer (Odocoileus spp.) and elk (Cervus spp.) make up the bulk of cougar diets in Washington and throughout western North America, but cougars are adaptable and opportunistic predators capable of taking prey ranging in size from small rodents and hares and rabbits to adult moose.
That said, about 3% of cougar diets in wildland-urban environments can consist of domestic animals; depredations of small livestock and pets represent the most common form of conflicts with people throughout their range. You can check out our Living with Cougars webpage for more information on Washington’s cougars including tips for preventing negative interactions.
