Atzeni, L., Cushman, S. A., Bai, D., Wang, J., Chen, P., Shi,
K., Riordan, P. (2020). Meta-replication, sampling bias, and multi-scale model selection:
A case study on snow leopard (Panthera uncia) in western China. Ecology and Evolution, , 1–27.
Abstract: Replicated multiple scale species distribution models (SDMs)
have become increasingly important to identify the correct variables
determining species distribution and their influences on ecological
responses. This study explores multi-scale habitat relationships of the
snow leopard (Panthera uncia) in two study areas on the Qinghai–Tibetan
Plateau of western China. Our primary objectives were to evaluate the
degree to which snow leopard habitat relationships, expressed by
predictors, scales of response, and magnitude of effects, were
consistent across study areas or locally landcape-specific. We coupled
univariate scale optimization and the maximum entropy algorithm to
produce multivariate SDMs, inferring the relative suitability for the
species by ensembling top performing models. We optimized the SDMs based
on average omission rate across the top models and ensembles’ overlap
with a simulated reference model. Comparison of SDMs in the two study
areas highlighted landscape-specific responses to limiting factors.
These were dependent on the effects of the hydrological network,
anthropogenic features, topographic complexity, and the heterogeneity of
the landcover patch mosaic. Overall, even accounting for specific local
differences, we found general landscape attributes associated with snow
leopard ecological requirements, consisting of a positive association
with uplands and ridges, aggregated low-contrast landscapes, and large
extents of grassy and herbaceous vegetation. As a means to evaluate the
performance of two bias correction methods, we explored their effects on
three datasets showing a range of bias intensities. The performance of
corrections depends on the bias intensity; however, density kernels
offered a reliable correction strategy under all circumstances. This
study reveals the multi-scale response of snow leopards to environmental
attributes and confirms the role of meta-replicated study designs for
the identification of spatially varying limiting factors. Furthermore,
this study makes important contributions to the ongoing discussion about
the best approaches for sampling bias correction.
|
(2002). Snow Leopard Survival Summit Group Photograph.
|
Anandakrishnan, M. B. (1998). The snow leopard: Elusive and endangered. The Environmental Magazine, 9(5), 18–19.
Abstract: The snow leopard has never been common, but there may be fewer than 4,000 left in its Himalayan habitat, and poaching and tourism-related development in the region could drive its numbers down further.
|
Andriuskevicius, A. (1980). Occurrance of Snow Leopards in the Soviet Union. International Pedigree Book of Snow Leopards, 2, 59–69.
Abstract: Outlines status and distribution of snow leopard in USSR, including comments on reserves created for the species.
|
Anonymous. (1984). Snow leopard trade in court.
|
Anonymous. (1992). The 7th International Snow Leopard Symposium Presentation Abstracts. In International Snow Leopard Trust, & Northwest Plateau Institute of Biology (Eds.), The 7th International Snow Leopard Symposium Presentation Abstracts (pp. 1–15). 7th International Snow Leopard Symposium.
|
Anonymous. (1996). Preserving the snow leopard and its habitat. The Rolex Awards for Enterprise Journal, 3.
|
Anonymous. (2000). Snow Leopard Smuggler Detained in Northwest China.
Abstract: Police have detained a man for trying to smuggle two snow leopards through the Xining Railway Station in northwest China's Qinghai Province. Ma Deliang was stopped by police after he attempted to pass the butchered snow leopards off as “beef” at a shop in Sichuan in southwest China. Suspicious of the contents in Ma's big sack, police asked experts from the local forestry bureau to check the meat and they found it to be flesh of two snow leopards, an endangered species on top state protection. Ma later confessed that he bought the dead snow leopards at a local market and wanted to smuggle them to Deyang, a city in southwest China's Sichuan province. Police also searched Ma's home and found dear heads, antlers and lynx and fox furs. Snow leopards live in highlands of altitudes between 3,000 to 6, 000 m above sea level. The population of the species has dwindled greatly since the 19th century.
|
Anonymous. (2000). Snow leopard management plan of Mongolia (draft).
|
Aryal, A. (2009). Final Report On Demography and Causes of Mortality of Blue Sheep (Pseudois nayaur) in Dhorpatan Hunting Reserve in Nepal.
Abstract: A total of 206 individual Blue sheep Pseudois nayaur were estimated in Barse and Phagune blocks of Dhorpatan Hunting Reserve (DHR) and population density was 1.8 Blue sheep/sq.km. There was not significant change in population density from last 4 decades. An average 7 animals/herd (SD-5.5) were classified from twenty nine herds, sheep per herds varying from 1 to 37. Blue sheep has classified into sex ratio on an average 75 male/100females was recorded in study area. The sex ratio was slightly lower but not significantly different from the previous study. Population of Blue sheep was seen stable or not decrease even there was high poaching pressure, the reason may be reducing the number of predators by poison and poaching which has
supported to increase blue sheep population. Because of reducing the predators Wolf Canis lupus, Wild boar population was increasing drastically in high rate and we can observed wild boar above the tree line of DHR. The frequency of occurrence of different prey species in scats of different predators shows that, excluding zero values, the frequencies of different prey species were no significantly different (ö2= 10.3, df = 49, p > 0.05). Most of the scats samples (74%) of Snow leopard, Wolf, Common Leopard, Red fox's cover one prey species while two and three species were present in 18% and 8%, respectively. Barking deer Muntiacus muntjak was the most frequent (18%) of total diet composition of common leopards. Pika Ochotona roylei was the most frequent (28%), and Blue sheep was in second position for diet of snow leopards which cover 21% of total diet composition. 13% of diet covered non-food item such as soil, stones, and vegetable. Pika was most frequent on Wolf and Red fox diet which covered 32% and 30% respectively. There was good positive relationship between the scat density and Blue sheep consumption rate, increasing the scat density, increasing the Blue sheep consumption rate. Blue sheep preference by different predators such as Snow leopard, Common leopard, Wolf and Red fox were 20%, 6%, 13% and 2% of total prey species respectively.
|