US Geological Survey (USGS) Grant: Modeling Climatically-Induced Vegetation Transitions in Alpine Ecosystems

The goal of this project is to promote cooperation between the USGS and CESU partners to evaluate the ecological and physiological responses of endangered species (i.e., bighorn sheep, pikas, etc.; and other alpine mammals) in the Sierra Nevada range. This research, while somewhat different in nature, is specifically focused on the physiological stress imposed by shifts and changes in the global ecosystem. It is important to note, these studies and research will not necessarily be implemented concurrently; the succeeding study may depend on research techniques and resources of the initial analysis.
Changes in distribution and abundance of alpine mammals in the Sierra Nevada range will be species-specific, with some species affected primarily by physiological stress, other species by changes in habitat, and others by altered forage quantity or quality. The hypothesis does not imply that climatic shifts will result in more restricted ranges and lower abundance for all five species. Rather, some species could be unaffected or even benefit from shifts in climate. Moreover, while climate could potentially trigger changes in alpine vegetation communities, feedbacks between climate and trophic interactions may result in some mammals “managing their own habitat.” Mammals play extremely important roles as herbivores and granivores in alpine ecosystems, so interactions between abiotic attributes of alpine ecosystems (climate, nutrients, water) with biotic processes (herbivory, granivory) could lead to multiple pathways resulting in alternative states for wildlife and vegetation communities.
This project is a multi-year study on past effects of global climate shifts and changes, and the physiological stress to bighorn sheep, pikas, and other alpine mammals that may result from the transition of alpine meadows. Research work of this project will require continued sampling of animal species, and the environment that make up the Sierra Nevada ranges for several years to come.
The USGS role in these studies will consists of providing experienced field support; as well as, logistics (GPS coordinates) that will aid in the locating the five alpine mammal species for development and testing of the environmental niche models; with the development of the topographic and land cover GIS layers; land cover classification, etc. models for the development of transition models; and provide resource selection functions for select alpine mammal species to adjust and compare different types of environmental niche models.