Greater Sage-Grouse Population Ecology

Science Center Objects

Greater Sage-grouse are iconic birds found only in the Great Basin of the western U.S. Known for their showy courting displays, sage-grouse rely on native sagebrush habitat to shelter their young. Dr. Pete Coates is providing resource managers with the tools and information they need to conserve sage-grouse as invasive plants, evolving wildfire patterns, and energy development change the Great Basin.

Dr. Pete Coates studies the population ecology of the Greater Sage-grouse, a species of bird found only in the Great Basin. As invasive plants, changing wildfire trends, and human land use alter this region, Dr. Coates’ projects will provide resource managers with new tools for conserving sage-grouse populations and native sagebrush habitat.

Population Modeling for Bi-State Sage-Grouse

The Bi-State population of Greater Sage-grouse straddles the borders of California and Nevada. These sage-grouse are physically isolated and genetically distinct from those found in the rest of their range, leaving them at a higher risk of population collapse. Dr. Coates is developing a conservation planning tool that uses results from statistical models of sage-grouse habitat suitability and space use. This project will help the U.S. Bureau of Land Management, U.S. Fish and Wildlife Service, and other partners assess and prioritize their management efforts for the Bi-State sage-grouse. Already, Dr. Coates’ study has supported decisions to place transmission lines and prioritize restoration projects.

 

A close-up photo of sagebrush, a vital part of the western sagebrush ecosystems

A close-up of sagebrush in the Great Basin. (Credit: Justin Welty. Public domain.)

Linking Incubation Behavior, Environment, and Nest Survival

Multiple factors such as climate, plant characteristics, and predator abundance can influence Greater Sage-grouse nest survival. Dr. Coates is studying the influence of these factors on incubation behavior and nest survival using videography collected over multiple years. This information will provide valuable information for managers focused on improving condition conducive to sage-grouse nest survival.

 

Winter Ecology of Greater Sage-Grouse

Greater Sage-grouse rely on sagebrush as a food source, particularly during winter, when they consume it almost exclusively. However, researchers do not know the extent to which sage-grouse rely on different species of sagebrush for food or cover, or how sage-grouses’ use of sagebrush changes with environmental factors like temperature and snow depth. Dr. Coates is studying the winter ecology of Greater Sage-grouse in eastern Nevada to answer some of these questions. Together, he and collaborators are evaluating sage-grouse use of different sagebrush species as a food source while accounting for the availability of sagebrush under different circumstances. These findings will help guide management plans that improve habitats to meet sage-grouses’ winter seasonal habitat requirements.

 

Population Modeling Across the Great Basin

Resource managers depend on range-wide sage-grouse studies to develop management guidelines for sagebrush habitat. However, most of these studies have occurred in the northeastern part of the sage-grouse’s range, and might not reflect all ecosystems across the Great Basin. To develop a more comprehensive understanding of sage-grouse habitat requirements, especially at smaller scales, Dr. Coates is working with scientists from BLM to study seven habitats across the Great Basin.

Dr. Coates also works with university and federal partners to develop multi-scale population monitoring frameworks, to identify changes in individual sage-grouse populations, and to test the link between altered sagebrush cover and sage-grouse communities. With this knowledge, resource managers will be able to understand sage-grouse response to local- and landscape-level changes in the environment.