California's non-native red fox metapopulation
Another red fox (meta-) population in California is composed of an admixture of introduced stock, largely originating from fur farms prevalent in California in the mid-1900s (apparently composed of Alaskan, Canadian, and eastern US stock). Exotic populations are discontinuously distributed throughout coastal and inland, low elevation, regions of the state where they threaten the persistence of several endangered species via predation or competition. I am working to identify source populations and patterns of connectivity among populations by investigating reproduction and body condition (via necropsy) and patterns of gene flow through microsatellite and mitochondrial analysis. Thus far, findings indicate that the population in the Monterey Bay area is a prolific source of dispersers to many other populations in the coastal regions and San Joaquin Valley, which may or may not be self-sustaining. In contrast, populations associated with the San Francisco Bay appear to be self-sustaining (also receiving dispersers from the Monterey Bay area) but do not appear to be an important source of dispersers to other populations. In addition to the applied value of understanding the metapopulations dynamics with an eye toward endangered species protection, this system provides an opportunity to address questions about the interplay between individual dispersal behavior in the context of specific habitat types. For example, how is it that red foxes in the San Francisco Bay area tend to remain in the salt marshes, while those associated with the estuaries and beaches of the Monterey Bay area disperse widely? Is it because the San Francisco Bay is simply higher quality habitat or might it be that the contrast between the San Francisco Bay marshes and adjacent upland (and urban) habitat is sufficiently stark that natal-habitat biased dispersal accounts for its insularity?
Collaborators and sample donors
John Perrine (UC Berkeley), John Pollinger (UCLA), Bob Wayne (UCLA), Dairen Simpson (freelance predator specialist), Bob Jones (UC Berkeley, Museum Vertebrate Zoology), Brian Cypher (CSU Stanislaus, USFWS/Endangered Species Recovery Program), Melissa Gilbert (Marine Wildlife Veterinary Care and Research Center), Jerry Wiscomb (USDA/Wildlife Services), Craig Coolahan (USDA/Wildlife Services), many, many Wildlife Services specialists