Preston Bruce Alden


Preston Alden with Island fox (Urocyon littoralis)--NOT study species.

Native Montane Red Fox (Vulpes vulpes) Ecology of the Southern Cascades and Nevada Ranges

I study native red fox populations (Vulpes vulpes) of the Southern Cascades and Nevada Ranges in the western United States where most contemporary native populations occur in relictual high montane zones. These cooler habitats closely resemble those that were widespread during the Pleistocene to which most native North American red fox are well adapted.   My interests area twofold: status of the Sierra Nevada red fox (V. vulpes necator) in Oregon and origins and population structure of red foxes in the Great Basin sky islands. 

Oregon Sierra Nevada red fox


A Sierra Nevada red fox at Crater Lake National Park. Photograph courtesy of Elena Thomas, NPS (May 2009).

The Sierra Nevada red fox is under review for listing under the US Endangered Species Act, prompted by its dangerously low numbers in two isolated California populations.  However, little is known about the status of this subspecies in the northern portion of its range, the Cascade Mountains of Oregon.  In cooperation with ODFW, USFS, University of Mississippi, National Park Service, Cascade Carnivore Project, Cascadia Wild, US Fish and Wildlife Service, and others, we plan to survey this area to collect noninvasive genetic samples that can be used to assess the distribution, abundance (genetic effective population size), genetic integrity, and connectivity of these populations.

Great Basin red fox

Nevada foxes

Red foxes of the Great Basin occur in three primary color morphs, shown here arranged from left to right: red, cross, and black (silver). Photograph courtesy of Randall Stoeberl.

In cooperation with NDOW, USFS, Nevada trapper, Randall Stoeberl, and others, we are investigating distribution and potential overlap between native relictual sky-island red fox populations and non-native red foxes originating from fur-farm stock. A fundamental question of my research is to characterize the genetic connectivity of indigenous sky-island red fox populations to test hypotheses associated with Island Biogeography Theory.  Additionally, this research is intended to inform conservation efforts associated with Greater sage grouse (Centrocercus urophasianus). 

The Greater sage grouse was designated a candidate species for listing under the US Endangered Species Act, currently pending decision to be rendered in 2015. An applied question of this research is to determine the native/nonnative origins of those red foxes overlapping sage grouse lekking grounds.  Non-native red fox are typically found at lower elevations primarily around urban areas, but also have been known to invade nearby habitats. In several locations throughout the study area red foxes prey on and may threaten Greater sage grouse.   We will collect red fox genetic samples from (1) sage-grouse predation hotspots, (2) high-montane locations of indigenous foxes, and (3) surrounding native and nonnative red fox populations potentially serving as sources of problem populations and recent expansion.