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Ale, S. B., Brown, J.S. (2009). Prey behavior leads to predator: a case study of the Himalayan tahr and the snow leopard in Sagarmatha (Mt. Everest) National Park, Nepal. Israel Journal of Ecology & Evolution, 55(4), 315–327.
Abstract: Rare, elusive predators offer few sightings, hindering research with small sample sizes and lack of experimentation. While predators may be elusive, their prey are more readily observed. Prey respond to the presence of a predator, and these fear responses may have population- and community-level consequences. Anti-predator behaviors, such as vigilance, allow us to sidestep the difficulty of direct field studies of large predators by studying them indirectly. Here we used a behavioral indicator, the vigilance behavior of the Himalayan tahr, the snow leopard’s main local prey, to reveal the distribution and habitat use of snow leopards in the Mt. Everest region of Nepal. We combined techniques of conventional field biology with concepts of foraging theory to study prey behavior in order to obtain insights into the predator’s ecology. The Himalayan tahr’s vigilance behavior correlates with the distribution of snow leopard signs. Tahr actually led us to six sightings of snow leopards. We conclude that behavioral indicators provided by prey offer a valuable tool for studying and monitoring stealthy and rare carnivores.
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Abramov V.K. (1974). Ecological basis of the conservation of large predators in USSR (Vol. Vol.I.).
Abstract: Problems of conservation of large predators (Felis tigris L., Panthera pardus L., Felis uncia Schreb., Acinonyx jubatus Schreb., Hyaena h¢…†n… L., Cuon alpinus Pall., Ursus maritimus Phipps, U.tibetanus Cuv.) inhabiting territory of USSR are discussed.
Keywords: Ussr; large predators; conservation problems; snow leopard.; 5850; Russian
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Adil, A. (1997). Status and Conservation of Snow Leopard in Afghanistan. In R.Jackson, & A.Ahmad (Eds.), (pp. 35–38). Lahore, Pakistan: International Snow Leopard Trust.
Keywords: Afghanistan; conservation; status; Palang-i-Barfi; Hindu-kush; Pamir; Ajar; park; parks; reserve; reserves; refuge; hunting; poaching; skin; fur; pelt; coat; distribution; ibex; Marco-Polo; sheep; markhor; predator; prey; protected-area; marco; polo; hindu; kush; browse; 2460
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Ahmad, A. (1994). Protection of Snow Leopards through Grazier Communities:Some Examples from WWF-Pakistan's Projects in the Northern Areas. In J.L.Fox, & D.Jizeng (Eds.), (pp. 265–272). Usa: International Snow Leopard Trust.
Abstract: Snow leopards occur near the snow line in northern Pakistan in the districts of Swat, Dir and Chitral of the Northwest Frontier Province (NWFP), Muzaffarabad district in Azad Kashmir and Gilgit and Baltistan districts in the Northern Areas. Although a number of protected areas are present in the form of national parks, wildlife sanctuaries and game reserves (Table 1) where legal protection is available to all wildlife species, including snow leopards, the status of this endangered species is not improving satisfactorily. The reasons are many and range from direct persecution by livestock owners to the less than strict management of protected areas.
Because of remote and inaccessible locations and lack of proper communication with local communities, government officials and nongovernmental organizations (NGOs) concerned with conservation find it difficult to obtain statistics on mortality of snow leopards. However, the killing of snow leopards is not uncommon. Because of the close and long-term association between local villagers and snow leopards, it is only through the support and cooperation of these peoples that protection of this endangered species can be assured against most of the existing threats. The effects of such cooperation has been clearly shown through some of the conservation projects of World Wildlife Fund (WWF) – Pakistan. Details of such projects and certain lessons that can be learned from these and similar projects are discussed in this paper. Keywords: conservation; Pakistan; Wwf; world-wildlife-fund; livestock; herders; herder; status; parks; park; reserve; refuge; protected-area; Dir; chitral; predator; prey; grazier; pelt; fur; coat; skin; poaching; Khunjerab; Marco-Polo-sheep; ibex; markhor; hunting; browse; protected; area; sheep; Marco-Polo; 2040
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Ahmad, I., Hunter, D. O., & Jackson, R. (1997). A Snow Leopard and Prey Species Survey in Khunjerab National Park, Pakistan. In R.Jackson, & A.Ahmad (Eds.), (pp. 92–95). Lahore, Pakistan: Islt.
Keywords: Slims; Islt; Wwf; predator; prey; Pakistan; Khunjerab; parks; park; reserve; reserves; refuge; Marco-Polo-sheep; blue-sheep; surveys; survey; transect; sighn; markings; marking; scrape; spray; ibex; tracks; pug marks; feces; livestock; kill; herder; herders; protected-area; blue; sheep; browse; international snow leopard trust; world wildlife fund; marco polo sheep; marco polo; pug; marks; protected area; protected areas; protected; area; areas; 2810
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Aizin B.M. (1969). Siberian ibex Capra sibirica Pall.
Abstract: It describes status of ibex in Kyrgyzstan, its distribution, behavioral patterns, enemies and competitors, etc. The enemies of ibex are snow leopard and wolf. All year round snow leopard preys on ibex its main food object and, therefore, should there be ibexes, snow leopards would be somewhere around. In winter, a considerable number of ibex dies from wolves. Sometimes dogs prey on ibex, too. Golden eagles and bearded vultures prey on young ibexes. However, poachers remain the most dangerous enemy.
Keywords: Kyrgyzsatn; Siberian ibex; distribution; life history; diet; predators; snow leopard.; 5890; Russian
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Ale S. (2005). Have snow leopards made a comeback to the Everest region of Nepal?.
Abstract: In the 1960s, the endangered snow leopard was locally extirpated from the Sagarmatha (Mt. Everest) region of Nepal. In this Sherpa-inhabited high Himalaya, the flourishing tourism since the ascent of Mt Everest in 1953, has caused both prosperity and adverse impacts, the concern that catalyzed the establishment of Mt. Everest National Park in the region in 1976. In the late 1980s, there were reports that some transient snow leopards may have visited the area from adjoining Tibet, but no biological surveys exist to confirm the status of the cats and their prey. Have snow leopards finally returned to the top of the world? Exploring this question was the main purpose of this research project. We systematically walked altogether 24 sign transects covering over 13 km in length in three valleys, i.e. Namche, Phortse and Gokyo, of the park, and counted several snow leopard signs. The results indicated that snow leopards have made a comeback in the park in response to decades of protective measures, the virtual cessation of hunting and the recovery of the Himalayan tahr which is snow leopard's prey. The average sign density (4.2 signs/km and 2.5 sign sites/km) was comparable to that reported from other parts of the cats' range in the Himalaya. On this basis, we estimated the cat density in the Everest region between 1 to 3 cats per 100 sq km, a figure that was supported by different sets of pugmarks and actual sightings of snow leopards in the 60 km2 sample survey area. In the study area, tahr population had a low reproductive rate (e.g. kids-to-females ratio, 0.1, in Namche). Since predators can influence the size and the structure of prey species populations through mortality and through non-lethal effects or predation risk, snow leopards could have been the cause of the population dynamics of tahr in Sagarmtha, but this study could not confirm this speculation for which further probing may be required.
Keywords: snow; snow leopards; snow leopard; snow-leopards; snow-leopard; leopards; leopard; region; Nepal; Report; International; international snow leopard trust; International-Snow-Leopard-Trust; trust; program; 1960; endangered; Sagarmatha; High; Himalaya; tourism; impact; establishment; national; national park; National-park; park; 1980; area; Tibet; surveys; survey; status; Cats; cat; prey; research; project; sign; transects; transect; length; valley; Response; hunting; recovery; Himalayan; tahr; density; densities; range; pugmarks; sighting; 60; study; population; predators; predator; structure; prey species; prey-species; species; populations; mortality; effects; predation; population dynamics
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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. |
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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Anonymous. (1992). International Specialists Discuss China's Threatened Cats. |