Predator-prey dynamics in a high-risk, low-reward landscape

Collaborators: Arthur Middleton, Emiliano Donadio, Jon Pauli, Michael Sheriff, Lindsay Rich, Owen Bidder

Landscapes of fear can dictate how animals utilize resources, move through space, and interact with other species. However, the strength of fear impacts on the ecology of large herbivores is still contentious and has yet to be thoroughly explored in a simple single-predator, single-prey system. We are exploring the dynamics of predator-prey interactions in San Guillermo National Park, Argentina, where rare high quality forage is also associated high risk of predation in order to understand the dynamics of risk effects on both predator and prey.

Large carnivore fear and humans as top behavioral predators

Collaborators: Justin Suraci, Mike Clinchy, Liana Zanette, Chris Wilmers

Fear is known to impact the ecology of wildlife, particularly by initiating risk-foraging tradeoffs and thereby altering foraging behavior. We have developed novel playback experimental methods to test puma risk-avoidance behaviors associated with anthropogenic sounds. Our approach quantifies the magnitude of puma perceived risk of humans and the consequences on their foraging efficiency, and can be used to understand the displacement of large carnivores as the behavioral top predator in human-dominated landscapes.

Dynamics of predator-prey interactions in human-dominated landscapes

Collaborators: Yiwei Wang, Chris Wilmers

Large carnivores that coexist with humans may alter their feeding and hunting behaviors as a result of an altered prey community, dynamic risk landscape, and changes in energetic requirements. We have examined puma prey habits and kill rates in relation to configuration and magnitude of anthropogenic development. Pumas that are exposed to higher anthropogenic development appear to increase kill rates on their primary prey while also diversifying their diet, likely due to the higher energetic costs of living among people and differential prey availability.

Impacts of human-induced activity shifts on niche partitioning

Collaborators: Austen Thomas, Taal Levi, Yiwei Wang, Chris Wilmers

Many animals become increasingly nocturnal with anthropogenic disturbance. These activity shifts are likely to alter species interactions, both in regard to how often species come into contact and how they partition resources. By developing a citizen science program called Conservation Scats, we collected 300 coyote, bobcat, and gray fox scats to test the relationship between human disturbance and diet overlap among competing carnivores. This research uses novel DNA metabarcoding techniques to explore the indirect effects of human activity on animal community dynamics.

Preserving “soft barriers” to animal movement in the residential matrix

Collaborators: Tim Duane, Chris Wilmers

The dominant paradigm of corridor design relies on least cost path analysis, which isolates a few high-quality corridors for protection. However, in human-modified landscapes, preserving areas with moderate development that still allow for animal movement may be a better strategy for promoting landscape connectivity. We are exploring the thresholds of development that deter puma movement, and prioritizing land acquisition to maintain permeability through areas of low-density development. By preventing housing densification and the development of “soft barriers” to movement, our approach refocuses connectivity goals on whole-landscape connectivity.