The Role of Epizootic Bovine Abortion Agent on Mule Deer Populations of the Mojave National Preserve in California and the Starkey Experimental Forest and Range in Oregon

Ticks, and the diseases they transmit play an important role in the health of wildlife and domestic animal populations. They can decrease the health of an animal through their effects on body condition and in extreme instances for survival (Merino et al. 2005). Ticks infesting deer populations cause deer to become anemic, and lose hair, weight, and muscle mass (McCoy et al. 2014). Ticks are also vectors for diseases such as Epizootic Bovine Abortion (EBA), which infects cattle (Teglas et al. 2005). In cattle, the agent of EBA (aoEBA) causes females to abort their fetus, but effects of the disease on mule deer (Odocoileus hemionus) are uncertain (Brooks et al. 2016). This research will examine exposure to the EBA agent among mule deer populations from the Mojave National Preserve in California and the Starkey Experimental Forest and Range in Oregon. Effects on mule deer body condition will also be determined in individuals who have been exposed to the EBA pathogen and in individuals with tick infestation. Results from this thesis conclude that in the two studied populations (Mojave National Preserve in California, and Starkey Experimental Forest and Range (hereafter Starkey) in Oregon) mule deer in the Mojave Desert were positive for the aoEBA, which was not present in mule deer at Starkey. Mule deer in the Mojave Desert also had higher tick infestations than mule deer at Starkey. Additionally, Ornithodoros coriaceus, the vector for the aoEBA, was not found on any Starkey deer. My results also indicated that the presence of the aoEBA was not directly correlated with tick infestation. Mojave mule deer, on average, had lower body condition scores than the Starkey mule deer. Although no correlation between aoEBA and body condition or tick infestation and body condition was evident, I suspect that increased abundance in tick infestation and more individuals with exposure to disease could negatively affect body condition of mule deer. Research in this field needs to be conducted to determine the true effects of infec