Climate change and the decline of an alpine-adapted carnivore: upward range shifts by competitors or changing prey communities?

Cate Quinn, Ph D student, NSF GRFP Fellow


Left: cross-pelage Sierra Nevada fox (Vulpes vulpes necator) female F2010-7; Center: unknown cross-pelage Sierra Nevada red fox; Right: Cate holding gray fox (Urocyon cinereoargenteus)--(Not the study species)

Historically Sierra Nevada red fox were present throughout the subalpine zone of the Sierra Nevada range in California and the southern Cascades of Oregon and California.  Over the last century the abundance and distribution of Sierra Nevada red fox have declined dramatically.  Today Sierra Nevada red fox persist at small numbers in two isolated populations in California and their range is poorly understood in Oregon.  Despite long-term trends of decline, the scarceness, difficulty of detection, and corresponding lack of basic ecological knowledge of this native subspecies have hampered conservation efforts. 

My research is aimed at increasing our understanding of the ecology of Sierra Nevada red fox and the potential factors limiting its population growth.  I use the recently rediscovered population north of (and in) Yosemite National Park, as a focal population to investigate how genetics, environment, and interactions with competitor and prey species affect the health of this Sierra Nevada red fox population.  Specifically, I am using a combination of noninvasive genetic sampling and satellite telemetry to 1) characterize the effective population size and degree of inbreeding present in the population, 2) approximate rates of reproduction and mortality, 3) identify fine-scaled habitat associations and key resource use, and 4) investigate spatial relationship with its competitor coyote.