Ecology of fear: A case study of blue sheep and snow leopards in the Nepal Himalayas

In this dissertation, I ask a simple question, “Do snow leopards deliberately seek sedentary livestock or do the numbers of blue sheep and their adaptive behaviors limit snow leopard hunting success that encourage livestock predation”? To answer this question, I applied concepts from optimal foraging theory and anti-predator behavior assuming that predators and preys are in a foraging game.; I tested foraging concepts in raccoons (Procyon lotor). I investigated effects of plant secondary compounds (oxalates and tannins) in its foraging behavior. I used artificial food patches to measure giving up density (GUD), or the amount of food left behind in foraging patches. Tannin treated foods were selected over oxalates and was more marked in summer. The compounds did not complement each other that could help balance the toxic effects of one toxin alone.; I studied effects of mountain lions (Felis concolor) on mule deer (Odocoileus hemionus) foraging behavior in southern Idaho. I used giving up density and vigilance as responses to a predator. Herd size marginally influenced vigilance during presence and absence of mountain lions. Vigilance increased in risky habitats. Foraging behavior was a combination of the effects of herd size, sex and age and distance from forest edge. Mule deer avoided riskier forest habitats (GUD_forest > GUD_edge > GUD_open).; In the snow leopard (Uncia uncia)-blue sheep ( Pseudois nayaur) system, I found livestock depredation increased with decrease in blue sheep numbers. Livestock numbers and snow leopard abundance (4.8–6.6/100 Km2) remained relatively constant over the past decade. At present, blue sheep numbers are increasing. I found evidence of foraging game as predicted. Blue sheep responded to snow leopard presence whereas livestock did not. Blue sheep combined behavior with habitat features and social age structure to balance its safety versus foraging demands. I found no evidence that snow leopards controlled blue sheep populations. Instead, severe winters recurring every 5–6 years seemed to regulate the population. The prediction that small populations of blue sheep increase apprehension, which makes it harder for snow leopards to catch them, may suggest that snow leopards opt to predate on livestock when resources become marginal.