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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. Keywords: attraction effect,contingency,dilution effect,fitness,group-size effect,many-eyes effect,predation risk,vigilance behaviour; predation; decline; potential; predators; predator; feeding; Animals; Animal; use; food; effects; Relationship; behaviour; methods; game; Interactions; interaction; factor; value; Energy
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Ale, S., & Whelan, C. (2008). Reappraisal of the role of big, fierce predators.
Abstract: The suggestion in the early 20th century that top predators were a necessary component of ecosystems because they hold herbivore populations in check and promote biodiversity was at Wrst accepted and then largely rejected. With the advent of Evolutionary Ecology and a more full appreciation of direct and indirect effects of top predators, this role of top predators is again gaining acceptance. The previous views were predicated upon lethal effects of predators but largely overlooked their non-lethal effects. We suggest that
conceptual advances coupled with an increased use of experiments have convincingly demonstrated that prey experience costs that transcend the obvious cost of death. Prey species use adaptive behaviours to avoid predators, and these behaviours are not cost-free. With predation risk, prey species greatly restrict their use of available habitats and consumption of available food resources. Effects of top predators consequently cascade down to the trophic levels below them. Top predators, the biggies, are thus both the targets of and the means for conservation at the landscape scale. |
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Meklenburtsev R.N. (1949). About ecology of ibex in Pamir (Vol. Vol. 28, edition 5.).
Abstract: Ibex is distributed all over the Pamir mountains, inhabiting rocks and canyons and ascending up to 5,500 m above sea level. In summer, ibex mostly feeds upon sedge and cereals, in winter wormwood. It keeps in herds containing 15 to 30 animals. The coupling period is December; kids being born at the beginning of June. The most dangerous predators are snow leopard and wolf. Ibex is a main commercial game species.
Keywords: Tajikistan; Pamir; ibex; distribution; number; diet; reproductive biology; predators; snow leopard; commercial use.; 7640; Russian
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Prakash, I. (1985). Asian predators of livestock. Parasites, pests and predators.World animal science, B2, 405–410.
Abstract: Outlines the distribution, status and predatory behaviour on livestock of Chinese alligator Alligator sinensis, gharial Gavialis gangeticus and several species of Crocodylus and Python; and of wolf Canis lupus, Asiatic jackal C. aureus, dhole (Indian wild dog) Cuon alpinus, brown bear Ursus arctos, Asiatic black bear Selenarctos thibetanus, striped hyaena Hyaena hyaena, clouded leopard Neofelis nebulosa, leopard (panther) Panthera pardus, tiger P. tigris, lion P. leo, snow leopard P. uncia, other Felidae and Viverridae. -P.J.Jarvis
Keywords: predators; asia; snow-leopard; livestock; status; prey; Panthera-uncia; distribution; predator; snow leopard; browse; panthera uncia; panthera; uncia; 870
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Sokolov G.A. (2003). Predatory mammals of Central Siberia, status of populations, influence of anthropogenic factors.
Abstract: The species resources of Siberia's fauna decrease from south to north. The highest diversity of species is observed in the mountain systems, the lowest in sub-zones of south and central taiga and steppe zone, where the cat family species are absent. During the last 50 150 years number of species has decreased two- to tenfold. Imperfect hunting management, farming, and mining operations resulted in transformation of the animal habitats. Population of fox, polecat, and sable has reduced; snow leopard and dhole becoming endangered species. If current tendencies continue to develop some species will disappear in the region in decades to come.
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Vyrypaev V.A. (1974). The influence of sarcoptosis on the population of Capra sibirica Pall. in Western Tien Shan (Vol. Vol. II.).
Abstract: Given is data concerning disease (sarcoptosis) of Siberian ibex (Capra sibirica) in Western Tien Shan. The carriers of the disease are adult males of Capra sibirica during distant migrations that as a rule take place in anticipation of snowy winters or owing to human influence. Ibexes are not merely infected with sarcoptosis but perish enmasse from the disease. In the first year the disease strikes down, in the main, migrants – adult males. Predators including snow leopard kill the weakened animals. During the recent five years the density of Carpa sibirica at the Chatkal Mountain-Forest Reservation dropped 2.3-fold as a result of sarcoptosis and owing to the migrations caused by the reduction of the population. Is recommended: 1. Stringent veterinary control at places of possible contacts between infected domestic animals and healthy wild ungulates. 2. Using modern technology migration routes of ungulates should be studied for elaborating effective measures of quarantine.
Keywords: Uzbekistan; Western Tien Shan; Chatkal nature reserve; sarcoptosis; predators; snow leopard.; 8560; Russian
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Zhiryakov V.A. (1990). Wolves' role in biocenosis of the Almaty nature reserve (North Tien Shan) (Vol. Vol. II.).
Abstract: The quantity of ungulates is high in the nature reserve: moral (100-120), roe deer (500-650), Siberian ibex (660-700), and wild boar (50-80). Moreover some 5,000 heads of livestock (mostly sheep) are grazed in a buffer zone in summer. Among big predators (snow leopard, bear, lynx) wolf kills about 40 percent of ungulates.
Keywords: Kazakhstan; Almaty nature reserve; ungulates; number; livestock; red deer; roe deer; ibex; wild boar; predators; brown bear; wolf; snow leopard.; 8780; Russian
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Voronov A.G. (1985). Predatory mammals.
Abstract: Predatory mammal in mountains are submitted by widely widespread species, such, as wolves, to a lynx and bears, and characteristic species for the high mountains, well adapted to mountain conditions and not going down below Alpine zone (a snow leopard, or irbis, occupying mountains of the Central Asia, etc.).
Keywords: predators; mountains; endangered species; Red Data bok; snow leopard.; 8540; Russian
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Zhiryakov V.A. (1989). The influence of the predators on population trend of the ungulates in the Almaty nature reserve.
Abstract: The data on predators and ungulates population dynamics in Almaty Nature reserve (Kazakhstan) in 1983-1987s are given. The number of snow leopard is stable (3-5 individuals), the density is 0.06 indi/1000 ha. An insignificant increase of Siberian ibex' number (660 to 700) with density of 36 indi/1000 ha is recorded.
Keywords: Kazakhstan; predators; ungulates; dencity; population trend; snow leopard.; 8770; Russian
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Sapozhnikov G.N. (1976). Wild sheep in Tajikistan.
Abstract: The monograph provides data concerning taxonomy, morphology, and age variability of wild sheep. There described distribution, number, population composition, behavioral patterns, reproduction, predators and parasites. Besides, a matter of conservation and sustainable use of the species is discussed. Together with wolf, snow leopard is called an enemy of O. o. vignei and argali (O. o. polii).
Keywords: Tajikistan; urial; argali; taxonomy; morphology; variability; life history characteristics; distribution; number; diet; behavior; parasites; predators; snow leopard.; 8060; Russian
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