Year of Award


Document Type


Degree Type

Master of Science (MS)

Degree Name

Systems Ecology

Department or School/College

Division of Biological Sciences

Committee Chair

Robert Crabtree

Commitee Members

Gordon Luikart, Michael Schwartz


Fox, Yellowstone, Beartooth, Distinct Population Segment, Native, Whitebark Pine


University of Montana

Subject Categories

Biodiversity | Ecology and Evolutionary Biology | Integrative Biology | Systems Biology


Montane red fox (Vulpes vulpes) populations across the western United States are genetically and morphologically distinct from foxes at lower elevations. These montane populations also share a preference for subalpine forest habitats. One hypothesis is that they stem from boreal forest-associated ancestors that expanded during the Pleistocene when boreal forests extended farther south than they do today. Forest habitat selection may therefore aid the persistence of native populations surrounded by non-native conspecifics. Alternatively, this behavior may be an avoidance mechanism in response to competition with larger coyotes (Canis latrans), or a product of the fox's natural adaptability. The red fox population at high elevations in the Greater Yellowstone Ecosystem (GYE) displays distinctive genetic and morphological characteristics, while it also lives in an environment without resident coyotes. I used genetic analyses to test hypotheses on the origin of this population and to examine population structure and gene flow across the GYE to investigate whether the high elevation population constitutes a discrete and significant population. I also used habitat selection analyses to examine forest habitat selection in this environment and test hypotheses of what may drive this behavior. I found that the GYE serves as a refugium for native red fox genetics, and that forest habitats play a critical role in the life histories of montane fox populations, especially since they hold important food resources used by red foxes such as whitebark pine (Pinus albicaulis) seeds. But selection of edge habitats was likewise strong. That suggests that resource scarcity and the need to access a variety of habitats with a variety of resources may be as much of or more important of a driver of habitat selection as are intrinsic preferences or competitive pressures. This project was an application of systems ecology studying how the evolution of a landscape affects the evolution of a species. It analyzed data relocations in an animal's movement path to the millennia between glaciations in a geological epoch. Its output benefits the scientific understanding of evolutionary ecology, the management and conservation of native species, and the general public's appreciation of ecology and natural resources. It also addresses whether the population could be considered a distinct population segment under the U.S. Endangered Species Act.



© Copyright 2015 Patrick Cross