Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Wildland Resources

Department name when degree awarded

Wildlife Science

Committee Chair(s)

Frederick Lindzey, Barrie Gilbert


Frederick Lindzey


Barrie Gilbert


Norbert DeByle


Vegetation structure of sites used by ruffed grouse (Bonasa umbellus) hens with brood, solitary grouse, drumming males, and nesting hens in northern Utah was measured in 1979 and 1980 . Univariate statistical techniques were used to determine general habitat characteristics of each group and discriminant function analysis was applied to the data to differentiate among groups. Most nests were located in maple stands (Acer grandidentatum and A. negundo) with dense tree canopies, low shrubs, and sparse ground vegetation. Drumming logs were most commonly found in densely stocked stands of aspen (Populus tremuloides) mixed with maple or chokecherry (Prunus virginiana) having a well-developed shrub layer and good horizontal visibility. The most important component of habitat used by solitary grouse was the dense shrub layer that apparently provided protection from precipitation, extreme temperatures, and predators. Hens with brood were commonly associated with aspen and mixed aspen stands which had open canopies, sparse shrub growth, and tall ground cover. Near the end of July, hens with brood began using habitat similar to that used by solitary grouse. The degree of horizontal visibility best separated habitat used by hens with brood and solitary grouse from the more open habitat associated with drumming logs and nest sites. Open tree canopy cover and tall shrubs best differentiated between habitat used by hens with brood from that used by solitary grouse. In general, many structural characteristics of habitat used by ruffed grouse in northern Utah appear similar to those reported in other areas of the species' range . Management strategies for use here should, however, be developed for small "islands" of habitat and emphasize enhancing structural and species diversity by planning for mixed aspen stands with a well-developed shrub layer.