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Jackson, R., Roe, J., Wangchuk, R., & Hunter, D. (2005). Camera-Trapping of Snow Leopards. Cat News, 42(Spring), 19–21.
Abstract: Solitary felids like tigers and snow leopards are notoriously difficult to enumerate, and indirect techniques like pugmark surveys often produce ambiguous information that is difficult to interpret because many factors influence marking behavior and frequency (Ahlborn & Jackson 1988). Considering the snow leopard's rugged habitat, it is not surprising then that information on its current status and occupied range is very limited. We adapted the camera-trapping techniques pioneered by Ullas Karanth and his associates for counting Bengal tigers to the census taking of snow leopards in the Rumbak watershed of the India's Hemis High Altitude National Park (HNP), located in Ladakh near Leh (76ø 50' to 77ø 45' East; 33ø 15' to 34ø 20'North).
Keywords: camera trapping; snow; snow leopards; snow leopard; snow-leopards; snow-leopard; leopards; leopard; felids; tigers; tiger; techniques; surveys; survey; information; factor; marking; behavior; Ahlborn; Jackson; habitat; status; range; census; India; Hemis; High; national; national park; National-park; park; Ladakh; leh
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Xu, F., Ming, M., Yin, S. -jing, Chundawat R.S., Marden, & Nui, Y. (2006). Preliminary Study on the Habitat Selection of Uncia uncia (Vol. 23).
Abstract: Uncia uncia is one of the rare large species on the brink of extinction in Felidae in the world, and inhabit only the Central Asian mountains. It is said that there are currently only 4500-7300 Uncia uncia surviving. During the period from September 2004 to July 2005, the habitat selection of Uncia uncia was investigated in some mountains in Xinjiang, including the eastern Tianshan Mountains, Beita Mountains, Altay Mounts and Mount Tumor National Nature Reserve. In several months of fieldwork, we got 171 sign samples of Uncia uncia and 123 random samples in total. Five habitat features, i.e., the elevation, topographic features, vegetation type, grazing status and ruggedness, are selected to compare the difference of selectivity of the Uncia uncia habitat selection. The Chi-square goodness-of-fit test and the binomial test are used to check the significance of Uncia uncia habitat selection, and the principal component analysis is used to find the primary factors in in the selection. The result s are as follows : (1) Uncia uncia selected all kinds of the habitat types , especially the elevation , topography , vegetation types and ruggedness ; (2) Ruggedness and the vegetation types are the preliminary factors for the habitat selection. Topography is the secondary factor ; (3) Uncia uncia prefer to inhabit in the rugged habitat s with moderate shrubberies , and they also like to leave signs in valley bottoms rather than hillsides.
Keywords: study; habitat; Habitat selection; selection; uncia; Uncia uncia; Uncia-uncia; Chinese; research; large; species; extinction; Felidae; central; mountains; mountain; Xinjiang; Tianshan Mountains; Altay; national; nature; reserve; fieldwork; sign; grazing; status; Test; analysis; primary; factor; topography; valley
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Xu, F., Ming, M., Yin, S. -jing, & Munkhtsog, B. (2006). Autumn Habitat Selection by Snow Leopard (Uncia uncia) in Beita Mountain, Xinjiang, China.
Abstract: Habitat selection of Snow Leopard ( Unica unica) in Beita Mountain of the Altay Mountain system in northeast Xinjiang was conducted from September to October 2004. Six habitat features of 59 sites used by Snow Leopard and 30 random plots were measured by locating 15 transects surveys in the study area . Vanderploge and Scaviaps selectivity index was used to assess Snow Leopardps selection for the different habitat parameters. Principal Component Analysis was used as the primary factor . The results indicated that Snow Leopard preferred the altitude between 2000 – 2 200 m and avoided 2 600 – 3 000 m ; selected cliff base , ridgeline and avoided hillside and valley bottom ; utilized the shrub and rejected the forest ; selected the nongrazing area and avoided the slightly broken region ; preferred north orientation and rejected the south orientation. The results show that grazing status , vegetation type , topography and the ruggedness are the primary factors for the habitat selection of Snow Leopard.
Keywords: habitat; Habitat selection; selection; snow; snow leopard; snow-leopard; leopard; uncia; Uncia uncia; Uncia-uncia; mountain; Xinjiang; China; Chinese; Altay; mountain system; system; 30; transects; transect; surveys; survey; study; area; analysis; primary; factor; 200; 600; Base; valley; Forest; region; south; grazing; status; topography
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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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