Describing Species-habitat Relationships

Evaluation of the condition, (e.g., risk levels) and spatial pattern of habitat for multiple species of concern provides essential context for the development of regionally based management and conservation strategies. A first step in habitat evaluation is defining the relationship between each species and environmental attributes, often vegetation cover types. For the Great Basin assessment, we identified vegetation associated with each species as habitat based on a recently completed landcover map (Comer and others 2002; [http://sagemap.wr.usgs.gov/]). This map was developed explicitly for regional assessment of sagebrush habitats across the Western United States and included the delineation of 8 sagebrush and 38 other landcover types in the Great Basin.

To define habitat relationships for Great Basin species of concern, we used the landcover types to construct a species-habitat association matrix, relying on literature sources and existing wildlife-habitat relationships databases. We then asked species experts to review the matrix, and we refined the habitat designations as necessary. This matrix was the basis for subsequent quantification of amount of habitat, and habitat at risk, within each species’ range in the Great Basin.