Biodiversity has been steadily declining in most ecosystems due to the direct and indirect effects of a growing human population. Large carnivores are particularly threatened by the negative effects of human population growth due to their slow life histories, wide-ranging behavior, and conflict with people over livestock depredation.The Maasai Mara National Reserve (henceforth, the Reserve) is located at the edge of the Mara-Serengeti ecosystem in southwestern Kenya, and is a stronghold for large carnivore conservation in East Africa. The Reserve has traditionally supported a great density and diversity of herbivores and large carnivore species year-round. However, current research indicates that anthropogenic activities immediately outside Reserve boundaries may be having negative effects on wildlife within the Reserve itself.My research investigates the short- and long-term effects of anthropogenic disturbance around the edges of the Reserve on wildlife populations within Reserve boundaries. First, I document longitudinal trends in the ecological and anthropogenic threats to wildlife. Next, I analyze the effects these threats have on herbivore and carnivore populations. I then test the hypothesis that spotted hyenas can serve as an indicator species in this ecosystem. Finally, management authorities play critical roles in conserving wildlife in the Reserve, so in my last dissertation chapter, I work to clarify the effects of prescribed burn management on African mammals.My research indicates that there have been declines in mammalian herbivore abundance and diversity from 1989-2013 in the Talek region of the Reserve. In this same region and time period, I document significant increases in temperature, the number of pastoralist settlements, the number of livestock grazing inside the Reserve, and the number of tourist lodges. Of all these threats to wildlife, livestock inside the Reserve had the largest negative effect on native herbivores. Also, the frequency of lion sightings in the Talek region have declined by 55 % between 2004-2008 and 2009-2013, while the sympatric population of spotted hyenas has undergone rapid growth. These changes appear to be due to the indirect effects of a growing human population. The speed of movement exhibited by spotted hyenas was affected by the turning angle of their trajectory, the animal’s proximity to anthropogenic disturbance, the time of day, the ambient temperature, the amount of rainfall, the amount of moonlight, and interactions between anthropogenic disturbance and social rank and anthropogenic disturbance and the time of day. The tortuosity of the paths of movement by spotted hyenas was affected by the speed of their movement, time of day, their proximity to anthropogenic disturbance, and the amount of rainfall. The speed at which spotted hyenas moved correlated with the diversity and abundance of resident herbivores up to 26 and 14 weeks into the future, respectively, and with the abundance of carnivores and migratory herbivores up to 20 weeks into the future; these results suggest spotted hyenas might be useful as in indicator species in this ecosystem. Prescribed burns affected the numbers of resident herbivores for 120 days, of small carnivores for 365 days, and of large carnivores for 120 days following the burning event.
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