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Warren E.Johnson, E. E. (2006). The Late Miocene Radiation of Modern Felidae: A Genetic Assessment (Stephen J.O'Brien Emma Teeling Agostinho Antunes W. J. M. Jill Pecon-Slattery, Ed.) (Vol. 311). Washington D.C.
Abstract: Modern felid species descend from relatively recent (<11 million years ago) divergence and
speciation events that produced successful predatory carnivores worldwide but that have confounded taxonomic classifications. A highly resolved molecular phylogeny with divergence dates for all living cat species, derived from autosomal, X-linked, Y-linked, and mitochondrial gene segments (22,789 base pairs) and 16 fossil calibrations define eight principal lineages produced through at least 10 intercontinental migrations facilitated by sea-level fluctuations. A ghost lineage analysis indicates that available felid fossils underestimate (i.e., unrepresented basal branch length) first occurrence by an average of 76%, revealing a low representation of felid lineages in paleontological remains. The phylogenetic performance of distinct gene classes showed that Y-chromosome segments are appreciably more informative than mitochondrial DNA, X-linked, or autosomal genes in resolving the rapid Felidae species radiation. Keywords: classification; divergence; Dna; Felidae; genetics; Miocene; mitochondrial; phylogeny; radiation; species; taxonomic
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McCarthy, K., Fuller, T., Ming, M., McCarthy, T., Waits, L., & Jumabaev, K. (2008). Assessing Estimators of Snow Leopard Abundance (Vol. 72).
Abstract: The secretive nature of snow leopards (Uncia uncia) makes them difficult to monitor, yet conservation efforts require accurate and precise methods to estimate abundance. We assessed accuracy of Snow Leopard Information Management System (SLIMS) sign surveys by comparing them with 4 methods for estimating snow leopard abundance: predator:prey biomass ratios, capture-recapture density estimation, photo-capture rate, and individual identification through genetic analysis. We recorded snow leopard sign during standardized surveys in the SaryChat Zapovednik, the Jangart hunting reserve, and the Tomur Strictly Protected Area, in the Tien Shan Mountains of Kyrgyzstan and China. During June-December 2005, adjusted sign averaged 46.3 (SaryChat), 94.6 (Jangart), and 150.8 (Tomur) occurrences/km. We used
counts of ibex (Capra ibex) and argali (Ovis ammon) to estimate available prey biomass and subsequent potential snow leopard densities of 8.7 (SaryChat), 1.0 (Jangart), and 1.1 (Tomur) snow leopards/100 km2. Photo capture-recapture density estimates were 0.15 (n = 1 identified individual/1 photo), 0.87 (n = 4/13), and 0.74 (n = 5/6) individuals/100 km2 in SaryChat, Jangart, and Tomur, respectively. Photo-capture rates (photos/100 trap-nights) were 0.09 (SaryChat), 0.93 (Jangart), and 2.37 (Tomur). Genetic analysis of snow leopard fecal samples provided minimum population sizes of 3 (SaryChat), 5 (Jangart), and 9 (Tomur) snow leopards. These results suggest SLIMS sign surveys may be affected by observer bias and environmental variance. However, when such bias and variation are accounted for, sign surveys indicate relative abundances similar to photo rates and genetic individual identification results. Density or abundance estimates based on capture-recapture or ungulate biomass did not agree with other indices of abundance. Confidence in estimated densities, or even detection of significant changes in abundance of snow leopard, will require more effort and better documentation. |
Saparbayev, S.K., & Woodward, D. B. (2008). Snow Leopard (Uncia uncia) as an Indicator Species and Increasing Recreation Loads in the Almaty Nature Reserve.
Abstract: The purpose of this research is to analyze the data on ecology, biology and dynamics of snow leopard population in the Almaty Nature Reserve and to identify if the increasing numbers of ecotourists could contribute to the decrease of Uncia uncia population. The results of the study show that increasing recreation loads in the Reserve and adjacent territories elevate the disturbance level to the snow leopard's main prey Siberian Ibex and to the predator itself that could result in a decrease of population of this endangered species or its total extinction.
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Janecka, J.E., Jackson, R., Yuquang, Z., Diqiang, L., Munkhtsog, B., et al. (2008). Population monitoring of snow leopards using noninvasive collection of scat samples: a pilot study (Vol. 11).
Abstract: The endangered snow leopard Panthera uncia occurs in rugged, high-altitude regions of Central Asia. However, information on the status of this felid is limited in many areas. We conducted a pilot study to optimize molecular markers for the analysis of snow leopard scat samples and to examine the feasibility of using noninvasive genetic methods for monitoring this felid. We designed snow leopard-specific primers for seven microsatellite loci that amplified shorter segments and avoided flanking sequences shared with repetitive elements. By redesigning primers we maximized genotyping success and minimized genotyping errors. In addition, we tested a Y chromosome-marker for sex identification and designed a panel of mitochondrial DNA primers for examining genetic diversity of snow leopards using scat samples. We collected scats believed to be from snow leopards in three separate geographic regions including north-western India, central China and southern Mongolia. We observed snow leopard scats in all three sites despite only brief 2-day surveys in each area. There was a high rate of species misidentification in the field with up to 54% of snow leopard scats misidentified as red fox. The high rate of field misidentification suggests sign surveys incorporating scat likely overestimate snow leopard abundance. The highest ratio of snow leopard scats was observed in Ladakh (India) and South Gobi (Mongolia), where four and five snow leopards were detected, respectively. Our findings describe a species-specific molecular panel for analysis of snow leopard scats, and highlight the efficacy of noninvasive genetic surveys for monitoring snow leopards. These methods enable large-scale noninvasive studies that will provide information critical for conservation of snow leopards.
Keywords: snow leopard; genetics; scat; noninvasive; survey.
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Ale, S. B., Yonzon, P., & Thapa, K. (2007). Recovery of snow leopard Uncia uncia in Sagarmatha (Mount Everest) National Park, Nepal (Vol. 41).
Abstract: From September to November 2004 we conducted surveys of snow leopard Uncia uncia signs in three major valleys in Sagarmatha (Mount Everest) National Park in Nepal using the Snow Leopard Information Management System, a standardized survey technique for snow leopard research. We walked 24 transects covering c. 14 km and located 33 sites with 56 snow leopard signs, and 17 signs incidentally in other areas. Snow leopards appear to have re-inhabited the Park, following their disappearance c. 40 years ago, apparently following the recovery of Himalayan tahr Hemitragus jemlahicus and musk deer Moschus chrysogaster populations. Taken together the locations of all 73 recent snow leopard signs indicate that the species is using predominantly grazing land and shrubland/ open forest at elevations of 3,000-5,000 m, habitat types that are also used by domestic and wild ungulates. Sagarmatha is the homeland of c. 3,500 Buddhist Sherpas with .3,000 livestock. Along with tourism and associated developments in Sagarmatha, traditional land use practices could be used to ensure coexistence of livestock and wildlife, including the recovering snow leopards, and ensure the wellbeing of the Sherpas.
Keywords: Nepal; recovery; Sagarmatha Mount Everest National Park; snow leopard; Uncia uncia; surveys; survey; snow; snow-leopard; leopard; uncia; Uncia-uncia; valley; Sagarmatha; national; national park; National-park; park; using; information; management; system; research; transects; transect; sign; areas; area; snow leopards; snow-leopards; leopards; 40; Himalayan; tahr; musk; musk-deer; deer; location; recent; species; grazing; land; Forest; habitat; domestic; wild; ungulates; ungulate; livestock; tourism; development; traditional; land use; land-use; use; wildlife
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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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Blomqvist, L., & Dexel, B. (2006). In Focus: Declining numbers of wild snow leopards.
Abstract: International collaboration to ensure the long-term survival of snow leopards (Uncia uncia) in the wild is today more acutely needed than ever! Trade in live snow leopards, their skins and bones, has during the last decade reached such extensiveness that the species is in danger of being wiped out from many of its former habitats. All recent surveys support declining populations throughout most of their range.
Keywords: asia; Cites; conflict; habitat loss; herder; laws; poaching; protection; snow leopard; threat; trade; Uncia uncia
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Helman, R. G., Russell, W. C., Jenny, A., Miller, J., & Payeur, J. (1998). Diagnosis of tuberculosis in two snow leopards using polymerase chain reaction (Vol. 10).
Abstract: The incidence of tuberculosis in zoological animal collections is low, and the disease is monitored through skin testing primarily in primates and artiodactylids.15,16 Other exotic animals are clearly at risk; tuberculosis has been described in elephants (Mycobacterium tuberculosis, M. bovis), rhinoceros (M. bovis), felids (M. bovis), foxes (M. bovis), birds (M. avium complex, M. tuberculosis, M. bovis), and reptiles, amphibians, and fish (cryophilic Mycobacterium species). 1,2,4,6,8-10,13,14,17 Mycobacterial infections in mammals and birds serve as a potential source of disease that can spread to other animals and to humans.7,15,16 In humans, M. bovis and M. tuberculosis are the most important mycobacteria in the USA.
Keywords: Disease; Mycobacterium; skin; snow leopard; zoo
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Taryannikov, V. I. (1986). Distribution, biology and current state of the number of the rare predatory mammals in W. Gissar. The Ecology, Protection, and Acclimatization of Vertebrates in Uzbekistan. Tashkent. |