Stressors to Greater Sage-Grouse

Science Center Objects

The Greater Sage-grouse is a small bird found only in the sagebrush steppe of the Great Basin. Invasions of non-native grasses, evolving wildfire patterns, grazing from livestock, and human land uses are changing this unique ecosystem. WERC’s Dr. Pete Coates studies sage-grouse populations to determine how these influences could affect the bird and other wildlife in the future.

WERC’s Dr. Pete Coates studies the effects of threats such as invasive predators, changing wildfire patterns, and human land use to the sagebrush steppe and Greater Sage-grouse of the Great Basin.

Conifer Encroachment  

Pinyon pines and juniper trees provide perches for predators like raptors and even common ravens, which prey on sage-grouse eggs. With the support of industry, non-profit organizations, state and federal agencies, Dr. Coates is developing high-resolution GIS maps of pinyon-juniper woodlands spreading into sagebrush ecosystems. These tools will help inform sage-grouse conservation programs within land and wildlife management agencies like the U.S. Bureau of Land Management and the U.S. Fish and Wildlife Service.

Greater sage-grouse in Wyoming.

A greater sage-grouse in Wyoming.(Credit: Bureau of Land Management, BLM. Public domain.)

Invasive Annual Grasses and Wildfire Patterns

The Great Basin is home to the “sagebrush sea,” an expanse of silvery-green shrubs that form the habitat for a diverse community of wildlife, including sage-grouse. Invasions of annual grasses such as cheatgrass have changed this landscape’s natural wildfire patterns, resulting in larger, more frequent and more severe blazes. Dr. Coates partners with scientists from the USGS Fort Collins and USGS Forest and Rangeland Ecosystem Science Centers to assess how evolving wildfires in the sagebrush steppe affect sage-grouse populations. Specific projects include:

  • Studying how sage-grouse might respond, behaviorally and demographically, to large fires and restoration efforts. Study results will help BLM identify effective management scenarios and restoration practices for sage-grouse of the Great Basin.
  • Using statistical models to predict how sage-grouse populations could respond to the combined influences of wildfires, rainfall, and soil temperature and moisture. Drier, warmer soil can affect the rate at which sagebrush recovers from a fire.
  • Investigating whether fuel treatments and fuel breaks can assist resource managers in conserving sage-grouse populations and habitat.

Land Use and Sage-Grouse Populations

Dr. Coates studies the long- and short-term effects of wind turbines, gold mining, geothermal energy production, hydraulic fracturing for oil, and transmission line development on sage-grouse in the Great Basin. His research team monitors changes in sage-grouse habitat selection, survivorship, and movement patterns. Study findings will support resource managers in minimizing the negative effects of human activities on sage-grouse.