Landscape Genetics of Sage Grouse

Science Center Objects

Greater and Gunnison sage-grouse populations are species considered for listing under the Endangered Species Act of 1973. Loss and fragmentation of sagebrush habitats are among the primary causes of decline in these species. A fundamental need for species conservation is to identify and subsequently maintain a set of connected populations. Landscape genetics combines the fields of population genetics and landscape ecology to investigate how landscape and environmental features affect connectivity, gene flow, population structure, and local adaptation. The goal of this new field of study is to provide information about the interaction between landscape features and microevolutionary processes such as gene flow, genetic drift, and selection allowing for the understanding of processes that generate genetic structure across space.

Trust Species and Habitats geneticists, in collaboration with other USGS scientists, Federal, State, and local agencies, and academia, are using genetic data in conjunction with landscape data (for example, habitat, roads, energy development, and elevation) to identify landscape features that function as barriers to movement for both Greater and Gunnison sage-grouse. These studies will help define biologically meaningful populations, provide information on levels of connectivity among populations, and define characteristics of barriers (including geographic distance, topographic features, and anthropogenic land uses) that affect dispersal and genetic exchange. Managers will be able to apply this understanding to focus conservation efforts in areas that will maximize benefits to sage-grouse populations.

The viability of the individual populations and long-term persistence of the species may be impacted by the ability of individual birds to move between populations. We are using genetic samples to infer connectivity across the species range and between leks within the Gunnison Basin to gain insight on which landscape or habitat features are contributing to the fragmentation of the species range. Our connectivity analysis within the basin will provide insight at a manageable scale and ultimately aims to inform current and future management possibilities by delineating corridors of movement and barriers to movement.

A male sage grouse struts his stuff on the sage steppe.