Project Summary for

Collaborative Research:  Modeling the Tradeoffs within Food-, Fear-, and

Thermal-Scapes to Explain Habitat Use by Mammalian Herbivores

CO-PIS: Jennifer S. Forbey BSU; Janet Rachlow UI; Lisa Shipley WSU

Assessing habitat quality is a primary goal of ecologists and land managers and is increasingly important as both climate and human-caused disturbances alter habitat features and potentially increase the risks they pose to organisms interacting with these habitats.  We sought to improve our ability to predict and manage these risks by creating 1) a better understanding of how animals perceive and respond to risky features in their habitats, and 2) an increased capacity to map the distribution of habitat risks relative to use by organisms over space and time. Using a model system consisting of two species of wild rabbits residing in a sagebrush steppe landscape in the western United States, we integrated laboratory and field work to assess simultaneous tradeoffs among dietary, predation, and thermal risks posed by habitats relative to foraging, escaping predators, and avoiding extreme temperatures across landscapes. This work yielded new theoretical and spatial models and field techniques that can be implemented in other plant-animal systems.

We found that animals perceive and respond to four habitat risks: nutrients in food, toxins in food, security cover, and thermal cover and that the avoidance of one risk over another depended on the characteristics and adaptations of the animal species (e.g., body size, tolerance for toxins in plants, required use of burrows) and environmental conditions (e.g., season, time of day).  Specifically, small, burrowing pygmy rabbits that specialize on chemically-defended sagebrush for food, accepted higher toxin risks to avoid risks associated with poorer-quality food and predation compared to larger cottontail rabbits that eat a wide range of foods and use a range of habitats, which used an opposite approach when choosing habitats.  Hot and cold temperatures influenced the value of food and use of plant cover and burrows by both rabbit species across days and seasons, and rabbits were able to shift their behavior to minimize temperature extremes. In our work, we integrated emerging technologies such as micro-Global Positioning System tags that measure fine-scale movements of small mammals and images collected from Unmanned Aerial Systems to map fine-scale variation in habitat features relative to habitat use. These results and technologies have increased our ability to predict resource selection and assess habitat quality when organisms are faced with complex decisions in natural environments.

In addition, we implemented a novel educational model that trained graduate, undergraduate, and high school students across three universities as part of a tiered mentoring program. These diverse participants engaged with local communities and regional biologists to identify best practices for managing habitat risks for wildlife and promote multiple uses of our public rangelands. This research and educational program broadened the scientific experience of over 300 middle and high school students, three K-12 teachers, over 90 undergraduates, and 13 graduate students across our western region of the US. Moreover, our program fostered strong collaborations with six other universities, including two predominantly undergraduate institutions, and state and federal land management agencies. The research contributed to society by providing models that predict how animals will alter their use of habitats in rapidly changing ecosystems and training the next generation of scientist capable of mapping and managing these ecosystems in the future.

Last Modified: 08/17/2018
Modified by: Jennifer Forbey