Following the Herd: Modeling Mule Deer Resource Selection in an Era of Solar Expansion

Habitat loss and fragmentation are occurring globally at unprecedented rates due toanthropogenic development, and is a major cause of biodiversity loss. Quantifying human impacts on natural environments and loss of biodiversity is difficult to quantify. The loss of biodiversity coupled with the urgency to transition to cleaner energy as a way to combat climate change, represents a major environmental challenge. Utility scale solar energy (USSE) is perceived as an effective way to reduce emissions from burning fossil fuels, and is being rapidly developed in remote areas that also are wildlife habitats. USSE requires a great deal of land to generate energy, and building in natural landscapes can cause a potential conflict between meeting alternative energy goals and preserving wildlife habitat. Mule deer (Odocoileus hemionus) are a large migratory animal that require a great deal of space and movement across the landscape is essential to meet life-history requirements. Mule deer can function as an indicator or umbrella species for other sagebrush-dependent species because they are migratory and require a great deal of space, and preserving habitat for them will benefit other species in the ecosystem. In many areas within the geographic range of mule deer, low elevations that correspond to areas occupied by mule deer during winter are increasingly being targeted for USSE development. In our study area of South-Central Oregon, winter range is classified as a sagebrush (Artemisia tridentata) steppe ecosystem and USSE developments are already targeting that landscape. The overall objective for this research was to identify habitat for mule deer to inform the siting of USSE facilitates and to understand the direct and indirect effects of USSE facilities on mule deer populations. We used resource selection functions to identify priority habitat, essential resources, and landscape attributes (e.g., elevation, slope, distance to water, and vegetation cover) for mule deer. We then used the resulting model to examine the potential effects of different development scenarios on habitat suitability. During winter, mule deer selected areas of low elevation and gentle slopes while avoiding areas near USSE facilities. Indeed, relative density of use increased with distance from solar development, and the negative effect of USSE on mule deer extended well beyond the boundary of the solar development. Furthermore, predicted habitat use declined as the number of solar facilities increased on the landscape. Our findings emphasize the strategic placement of USSE in areas of previously degraded landscapes or in close proximity to a town. Building in these areas may reduce human impact to natural environments while continuing to meet alternative energy goals.

Level thesis:degree_level

Master’s Degree

Year dc:date.issued

2026

Author dc:creator

• Grock (Nakamura), Hanna

Advisor dc:contributor.advisor

• Stewart, Kelley

Committee members dc:contributor.committeemember

• Shoemaker, Kevin
• Bowles, Jamie
• Nolin, Anne

Language dc:language.iso

en_US, English

Repository record dc:identifier.uri

https://scholarwolf.unr.edu/handle/11714/11892

OAI identifier oai:identifier

oai:scholarwolf.unr.edu:11714/11892