Lead CDFW biologists: Mike Morrison, Jane McKeever
The White Mountains are located in Inyo and Mono counties, CA, east of Bishop, CA, and range in elevation from 1,700 m at the lower elevations of the winter range to over 4,375 m at the higher elevations. The study area contains numerous habitat types as it transitions in elevation. Desert woody scrub is the dominant habitat at lower elevations. Intermediate elevations are dominated pinyon juniper woodland, the main trees being pinyon pine (Pinus monophylla) and Utah juniper (Juniperus osteosperma). Higher elevations support subalpine conifer forest with the dominant trees being bristlecone (Pinus longaeva) and limber pine (Pinus flexilis). Alpine tundra is found at the highest elevations and is dominated by buckwheat (Eriogonum gracilipes) and phlox (Phlox covillei). Numerous large drainages flow from the east and west slopes of the White Mountain range providing riparian vegetation dominated by black cottonwood (Populus trichocarpa) and willow (Salix sp.) at the lower elevations and quaking aspen (Populus tremuloides) at the higher elevations.
The White Mountain deer study grew out of the need for the Department to determine the composition of the White Mountain deer herd, as well as delineate seasonal use areas, such as key wintering and fawning areas, identify habitat characteristics that may be important to these deer, and finally, identify factors that limit this herd. There was concern that the deer population was experiencing a decline. To monitor this population a deer capture and radio-collaring effort was needed. This became a cooperative research project with University of Nevada, Reno and part of a graduate student's field work. The research began in 2004 and the deer collaring effort ended in spring 2009.
One aspect of this research is documenting the encroachment of pinyon-juniper woodland habitat along the eastside slopes of the White Mountains and understanding its effect on the deer herd. Deer utilize pinyon pine and Utah juniper for cover, and pine nuts add a food source during winter. However, over the past 120 years in the western United States, pinyon pine and Utah juniper have gained dominance in the woodland habitat, and juniper, with no forage value, has become more abundant and invasive. As the pinyon-juniper woodland expands downslope, it is overtaking the grassland and alluvial fans and hence decreasing the shrub and herbaceous layers that are important high quality forage for deer. In order to quantify the change in density and expansion of the pinyon-juniper woodlands, biologists are using orthorectified historic aerial photos (PDF) from 1950 to compare to aerial photos of the same areas in 2005.