Habitat Selection by Northern Sagebrush Lizards (Sceloporus graciosus graciosus) in the Columbia Basin, Oregon

Habitat selection by northern sagebrush lizards (Sceloporus graciosus graciosus) was investigated on the US Navy's 19,400-ha Naval Weapons Systems Training Facility Boardman near Boardman, Oregon, as part of an integrated multi-resource research program. The objectives of the study were to determine what plant communities these lizards occupied and what specific habitat components they selected within these types. In general, northern sagebrush lizards occupied plant communities dominated by big sagebrush (Artemisia tridentata) and antelope bitterbrush (Purshia tridentata) and largely avoided communities dominated by gray rabbitbrush (Chrysothamnus nauseosus), cheatgrass (Bromus tectorum), and western needle-and-thread grass (Stipa comata). Usage within bitterbrush and sagebrush habitats was determined by comparing habitat characteristics at sites occupied by lizards (n = 15 per plant community) with sites randomly located within each plant community (n = 15 per plant community). Results showed that these lizards selected for areas with significantly higher than average bare soil coverage and significantly lower than average coverage of grass, litter, and lichen. Furthermore, all sites occupied by lizards were located in sandy soils even though this soil type represented only about half of the surface soil texture available. Overall, northern sagebrush lizards selected for sand blows with approximately 20% shrub coverage and avoided areas with loamier soils covered (stabilized) with grass, litter, or lichen.