Predator-prey space-use and landscape features influence movement behaviors in a large-mammal community

Predator hunting strategies, such as stalking versus coursing behaviors, are hypothesized to influence antipredator behaviors of prey and can describe the movement behaviors of predators themselves. Predators and prey may alter their movement in relation to predator hunting modes, yet few studies have evaluated how these strategies influence movement behaviors of free-ranging animals in a multiple-predator, multiple-prey system. We fit hidden Markov models (HMM) with movement data derived from >400 GPS-collared ungulates and large predators in eastern Washington, USA. We used these models to test our hypotheses that stalking (cougars [Puma concolor]) and coursing (gray wolves [Canis lupus]) predators would exhibit different broad-scale movement behaviors consistent with their respective hunting strategies in areas that increased the likelihood of encountering or capturing ungulate prey (e.g., habitats selected by deer [Odocoileus spp.]). Similarly, we expected that broad-scale movement behaviors of prey would change in response to background levels of predation risk associated with each predator’s hunting strategy. We found that predators and ungulate prey adjusted their broad-scale movements in response to one another’s long-term patterns of habitat selection but not based on differences in predator hunting strategies. Predators changed their movement behaviors based on the type of prey, whereas ungulates generally reduced movement in areas associated with large predators, regardless of the predator’s hunting strategy. Both predator and prey movements varied in response to landscape features but not necessarily based on habitat that would facilitate specific hunting behaviors. Our results suggest that predators and prey adjust their movements at broad temporal scales in relation to long-term patterns of risk and resource distributions, potentially influencing their encounter rates with one another at finer spatiotemporal scales. Habitat features further influenced changes in movement, resulting in a complex combination of movement behaviors in multiple-predator, multiple-prey systems.

Methods
Telemetry relocation data were collected using Global Positioning System (GPS) radio collars (make and model varied by species) affixed to >400 individual animals, including adult female elk, mule deer, and white-tailed deer, and adult female and male cougars and wolves in two study areas in eastern Washington, USA, 2017 - 2021. Location data were used to generate resoure selection functions (RSFs), which were then used to predict the relative probability of selection of each species across each study area. Location data were further used to estimate the effects of predation risk (represented by the RSFs) and landscape features associated with predator hunting mode on animal movement using hidden Markov models (HMMs). Additional capture and handling information, as well as descriptions of data cleaning and analyses, are described in detail in text (Bassing et al. in review).