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Ale, S., & Brown, J. (2007). The contingencies of group size and vigilance (Vol. 9).
Abstract: Background: Predation risk declines non-linearly with one's own vigilance and the vigilance of others in the group (the 'many-eyes' effect). Furthermore, as group size increases, the individual's risk of predation may decline through dilution with more potential victims, but may increase if larger groups attract more predators. These are known, respectively, as the dilution effect and the attraction effect.
Assumptions: Feeding animals use vigilance to trade-off food and safety. Net feeding rate declines linearly with vigilance.
Question: How do the many-eyes, dilution, and attraction effects interact to influence the relationship between group size and vigilance behaviour?
Mathematical methods: We use game theory and the fitness-generating function to determine the ESS level of vigilance of an individual within a group.
Predictions: Vigilance decreases with group size as a consequence of the many-eyes and dilution effects but increases with group size as a consequence of the attraction effect, when they act independent of each other. Their synergetic effects on vigilance depend upon the relative strengths of each and their interactions. Regardless, the influence of other factors on vigilance – such as encounter rate with predators, predator lethality, marginal value of energy, and value of vigilance – decline with group size.
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Gosselin, S. J., Loudy, D. L., Tarr, M. J., Balistreri, W. F., Setchell, K. D., Johnston, J. O., et al. (1988). Veno-occlusive disease of the liver in captive cheetah. Vet Pathol, 25(1), 48–57.
Abstract: Liver tissues from 126 captive cheetah were evaluated by light microscopy and histochemistry; eight animals were evaluated by electron microscopy. The main hepatic lesion, a vascular lesion resembling veno- occlusive disease (VOD) of the liver and characterized by subendothelial fibrosis and proliferation of smooth muscle-like cells in the central veins, was seen in 60% of the sexually mature cheetah. Although this hepatic vascular lesion was seen in cheetah as young as 1 year of age, the most severe lesions, usually associated with liver failure, were found in cheetah between the ages of 6 and 11. There was no sex predisposition, and in approximately 40% of the VOD cases, liver disease was not suspected clinically or at necropsy. VOD was found in other felidae, especially in the snow leopard. High levels of vitamin A in livers, as well as in diets of the cheetah, could be a contributing factor in the development of VOD in some groups of cheetah.
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Sunquist, F. (1997). Where cats and herders mix. (snow leopards in Tibet and Mongolia). International Wildlife, 27(1), 27–33.
Abstract: The snow leopard inhabits a huge range of territory which encompasses some of Central Asia's most bleak and inhospitable terrains. The animal herders in these regions are desperately poor and yet they have agreed to cooperate with conservation groups in protecting the snow leopard. The World Wildlife Foundation has worked to create a refuge on the Pakistan-China border. Sheep herders near Askole, a village in the Baltistan region of northern Paksitan, drive their flocks past stone enclosures. The area is also home to snow leopards. With their natural prey dminished, leopards in 13 countries of central Asia occasionally feed on livestock, putting the cats on a collision course with mountain peoples.
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Fox, J. L., & Chundawat, R. S. (1988). Observations of snow leopard stalking, killing and feeding behavior. Mammalia, 52(1), 137–140.
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Rana, B. S. (1997). Distinguishing kills of two large mammalian predators in Spiti Valley Himachal Pradesh. J.Bombay Nat.Hist.Soc, 94(3), 553.
Abstract: The author studied livestock killed by predators in the Spiti Valley, India, to determine what species had killed yaks, horses, donkeys, and other domestic animals. Eleven of the kills examined were made by snow leopards and six by the Tibetan wolf. Wolves were involved in surplus killings, while snow leopards kill as food is needed. lgh
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Seidensticker, J., & Lumpkin, S. (1996). The adaptable leopard; unfortunately it's no match for modern man. Wildlife Conservation, 99(3), 52.
Abstract: Abstract: Leopards' adaptability has become the species' vulnerability. The animals do not hesitate to eat rotting flesh and will come back repeatedly to their meal, if disturbed. People have taken advantage of this by lacing carcasses with poison. Leopards are moderate in size compared to other cats, are stealthy and can live in areas as diverse as rain forests and deserts.
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Shrestha, R., & Wegge, P. (2006). Determining the composition of herbivore diets in the Trans-Himalayan rangelands: A comparison of field methods. Journal of Rangeland Ecology and Management, 59(5), 512–518.
Abstract: In late summer, in a semi-arid mountain range in Nepal, we compared 3 field methods for determining the botanical composition of herbivore diets. Data were collected from the same animals belonging to 1 herd of domestic yak (Bos grunniens) and 2 herds of mixed smallstock, consisting of domestic goats (Capra hircus) and sheep (Ovis aries). Bite count, feeding site examination, and microhistological analysis of feces gave different estimates of forage categories and plant species in both animal groups. Because yaks grazed in other vegetation communities when not observed for bite-counts and feeding signs, the results from the latter methods could not be compared directly with that from fecal analysis. In smallstock, feeding site examination gave higher estimates of graminoids and lower estimates of shrubs than the other 2 methods, probably because all feeding signs on shrubs were not detected. Bite-counts and fecal analysis gave comparable results, except that forbs were underestimated by fecal analysis, presumably due to their more complete digestion. Owing to the difficulty in collecting samples that are representative of the entire grazing period and the problem of recording feeding signs correctly, both feeding site examination and bite-counts are unsuitable methods for studying the food habits of free ranging domestic and wild herbivores. Microhistological analysis of feces appears to be the most appropriate method, but correction factors are needed to adjust for differential digestion. The systematic use of photomicrographs improves the speed and accuracy of the fecal analysis.
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Lu, Q., Xiao, L., Cheng, C., Lu, Z., Zhao, J., Yao, M. (2021). Snow Leopard Dietary Preferences and Livestock Predation Revealed by Fecal DNA Metabarcoding: No Evidence for Apparent Competition Between Wild and Domestic Prey. Frontiers in Ecology and Evolution, 9(783546), 1–14.
Abstract: Accurate assessments of the patterns and drivers of livestock depredation by wild carnivores are vital for designing effective mitigation strategies to reduce human-wildlife conflict. Snow leopard’s (Panthera uncia) range extensively overlaps pastoralist land- use and livestock predation there is widely reported, but the ecological determinants of livestock consumption by snow leopards remain obscure. We investigated snow leopard dietary habits at seven sites across the Sanjiangyuan region of the Qinghai– Tibetan Plateau (QTP), an area central to the species’ global range. Snow leopard abundance, wild prey composition, and livestock density varied among those sites, thus allowing us to test the effects of various factors on snow leopard diet and livestock predation. Using DNA metabarcoding, we obtained highly resolved dietary data from 351 genetically verified snow leopard fecal samples. We then analyzed the prey preferences of snow leopards and examined ecological factors related to their livestock consumption. Across the sites, snow leopard prey was composed mainly of wild ungulates (mean = 81.5% of dietary sequences), particularly bharal (Pseudois nayaur), and supplemented with livestock (7.62%) and smaller mammals (marmots, pikas, mice; 10.7%). Snow leopards showed a strong preference for bharal, relative to livestock, based on their densities. Interestingly, both proportional and total livestock consumption by snow leopards increased linearly with local livestock biomass, but not with livestock density. That, together with a slight negative relationship with bharal density, supports apparent facilitation between wild and domestic prey. We also found a significant positive correlation between population densities of snow leopard and bharal, yet those densities showed slight negative relationships with livestock density. Our results highlight the importance of sufficient wild ungulate abundance to the conservation of viable snow leopard populations. Additionally, livestock protection is critically needed to reduce losses to snow leopard depredation, especially where local livestock abundances are high.
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