The invasion, dynamics, and impacts of infectious disease in Yellowstone's wolf population

Open Access
Author:
Almberg, Emily Staggs
Graduate Program:
Ecology
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
January 27, 2015
Committee Members:
  • Peter John Hudson, Dissertation Advisor
  • Isabella Cattadori, Committee Chair
  • Matthew Joseph Ferrari, Committee Member
  • Matthew Brian Thomas, Committee Member
  • Andrew Dobson, Special Member
Keywords:
  • parasite invasion
  • social immunity
  • ecoimmunology
  • gray wolf
  • sarcoptic mange
Abstract:
My research seeks to address the broad questions of how parasites invade, their individual and population-level impacts on their hosts, and the drivers of heterogeneity observed in infection risk, severity, and outcome within the system of reintroduced gray wolves of Yellowstone National Park, Wyoming. Using a long-term dataset on wolf demographics, serology, infection status with mange, and several indices of immune function, I address the following specific questions: (1) What are the spatial and temporal dynamics and the biological impacts of parasite invasion on a reintroduced host? (2) Does infection risk and cost scale with social group size? And (3) Do indices of immune responsiveness help explain some of the variation we see in infection risk and survival? Chapter 1 documents the invasion of several important pathogens within the Yellowstone wolf population, establishing a baseline for the dynamics and impacts of infectious disease within this population. Chapter 2 details how the risk of infection with sarcoptic mange appears to be independent of wolf social group size, but that the costs associated with infection can be completely offset by living in a large social group, presumably as a result of cooperative care, food acquisition, and territory defense. Chapter 3 presents evidence that several indices of innate immune responsiveness are related to survival given infection with either canine distemper virus or sarcoptic mange. I conclude with an overview and synthesis of my work as well as a discussion of future research avenues.