Date of Award:
Master of Science (MS)
Department name when degree awarded
Michael L. Wolfe
The dynamics of pathogen and host relationships relative to disease transmission in wildlife populations are important ecological processes to understand, particularly since spatial dynamics of disease can be driven by movement, behavior, and dispersal of animals. Chronic Wasting Disease (CWD) is an example of this important interface, where little is known regarding origin of the disease or routes of transmission. Surveillance data for CWD in free-ranging mule deer indicates that breeding-age male deer have 2-4 times higher prevalence rates than females or younger age males. In an effort to understand differences that might increase risk for exposure to CWD infective agents, I used GPS data to examine breeding behavior and home range sizes of mule 11 deer. GPS radiocollars were placed on adult (> 2 ½ years) males, females, and young ( < 2 ½ years) males. Data collected during the breeding season was used to infer visitation rates of males to females. Cluster analysis was used to separate data into periods of movement (spatio-temporal clusters) and non-movement. Females formed more spatio-temporal clusters and movement paths than males. However, males spent more time moving, had more long-term periods of movement, moved an estimated 1 km/day more than females, and had more tortuous movement paths. Male home ranges for winter, summer, and breeding seasons were also larger than those of females. Overall, data indicates that males may have an increased risk of exposure to CWD relative to females, because of larger movements and greater space use. These male behavioral differences may result in increased encounter rates with CWD infectious material through greater exposure in the environment to sources such as carcasses from infected animals, their excreta, or contaminated soils. Furthermore, during the breeding season increased male sociality, as suggested by increased movement rates and movement path tortuousity, combined with larger space use may further enhance direct contact with infected individuals and increase exposure to excreta sources such as feces and alimentary secretions due to licking and tending behaviors.
McFarlane, Leslie R., "Breeding Behavior and Space Use of Male and Female Mule Deer: An Examination of Potential Risk Differences for Chronic Wasting Disease Infection" (2007). All Graduate Theses and Dissertations. 6619.